Hi, I have a Condor 46 manlift that has an air cooled Wisconsin V-4 dual fuel engine. I have only run it on Propane. It starts like a champ when cold but even after a minute or two of Running, It will not restart. Takes a few hours of cooling to start again. I would not have though that Propane would vapor lock. Hoping it is an easy fix. Any advice appreciated.
I'd start with seeing if there's spark, maybe give it a shot of starting fluid while cranking, if it runs for a second then there's spark. Or find a volunteer to hold onto one of the wires Only after you know that it has spark, I'd see which of those relay/solenoid/gizmos isn't operating when it's hot. Since you seem to assume it's fuel, I'll assume that the starter is cranking fine, just not firing, right?
Yes, I am assuming it is fuel, cranks just fine, just won't catch unless it is cool, then it fires right up. Just like you, I think it is a solenoid that does't work when hot. I am hoping someone will know which one based on the symptoms.
Pretty common for the valves to stick in the guides
Do mean inside a solenoid? If so, which one?
Jumper 12V to that solenoid where the gas line connects, fuel shutoff valve, or check with a meter or test light to see if it's getting power when cranking. Engine may not be pulling enough vacuum hot to make the diaphram valve there connect, or some electrical issue as suggested.
I think he means the valves and guides in the engine block. Combine that with Iantraxco's suggestion and the stuck valve keeps the engine from developing enough vacuum to start... But I'd still try the starting fluid to confirm spark.
Wouldn't valves stuck in the engine cause a catastrophic mechanical failure? This is the Solenoid that regulates the Propane flow. I flipped the image 180 degrees to read the label. I ran out of propane fooling around with it today so I will refill and try again. In the mean time, anyone have a good source for solenoids? I have a couple others that need replacing as well.
One of the other solenoids I need to replace; .
Looks like a flathead design, the valves are off to one side and face up, they can and do stick open sometimes. Solenoids rarely fail in my experience, though the mechanical part of the valve might. If that as valve isn't opening, it's more likely not getting power or has an intermittent ground. Correoded connections can give you fits on these kinds of systems. It looks like they grounded it to the valve cover screw, clean the eyelet that's there, I would put another black wire on that screw, and run it to a really good ground for starters. That second one, is that the throttle solenoid? If it's working I wouldn't worry about the boot being rotted away, but that's just me.
Great suggestions. I have fought grounding issues in a boat before and you aren't kidding, Grounds are important. The other is a throttle solenoid. It actually did fail. I have just been using the the machine on rabbit instead of turtle until I finish this painting project. Now that I have to tackle another issue, might as well do both. Any suggestions on where to get a replacement? Thanks guys
Picture right side up; .
Check the valve lash,or do a cold/hot compression check.
Have you taken Delmer's suggestion to see if when it won't start that you have good spark? Ignition components can fail when hot but work fine cold. Also as others have suggested have you checked hot compression and compared to cold. If you have spark and compression when hot then start thinking about fuel problems.
Just hooked the fresh Propane up. Started instantly and effortlessly. Ran on fast idle for 5 minutes, shut it down and tried to start it. NADA. Sounds like it wants to catch and fire up but just won't. Sprayed starting fluid into the air cleaner and nothing, when I shot more in, it bogged it down like I was flooding it. Could it be the cheap ole' coil? Also, the solenoid that is on the propane fitting pictured above. The black (ground?) wire on the face connects to the post on the side which has the second black ground wire connected, then there is only one wire that runs over to the diaphram that is attached to the exhaust manifold, It is attached to the faded red plastic block in this cropped picture from the one I posted in the original post. There is no ground to this solenoid. .
Waited 30 minutes and tried again, engine still pretty warm, coil not hot but warm, Fired up instantaneously. Just to describe more fully. The Propane Solenoid runs one wire to the diaphragm on the exhaust manifold. I took that apart to see if there is a tear, the diaphragm is in good condition. Also, there is no hole communicating with exhaust thru that little pipe so it is not a vacuum or pressure operated unit. Looks like it has a temp sensor in it. The post on the red block has 2 wires. One to the Propane solenoid and one to the + post on the coil for voltage.
The diaghram unit is connected to the intake section of that manifold unit, so it should be connected to vacuum. Since both wires are on the same terminal it's kinda irrelevant as someone has bypassed the vacuum safety switch. The solenoid propane valve has two black wires coming out of the coil, one is grounded by the screw that is top center of the coil cover, the other goes to the insulated post where it joins with the red wire feeding power. Since the engine failed to light on starting fluid I would guess you have an ignition problem, OR it's remotely possible you have too much propane to light off when hot. Not sure how the coil is wired on this engine, if it has an internal or external resistor? If it's external there should be a bypass wire coming from the starter solenoid to give the coil a full 12 volts for hotter spark when starting. Check your coil voltage cold and hot, both with just the power on and then when cranking, check the points for condition and correct gap, etc. I am assuming this is old enough it doesn't have any electronic ignition components in it. Just a couple suggestions......
If it won't fire on starting fluid, I think Delmar hit it on the head, no spark. Have you checked the spark when trying to restart. I'd spend $10.00 on points and condenser before I started replacing solenoids. Condensers have been failing when warm forever. Could also be the coil that loses power when hot.
Would the fact that the Idle speed solenoid is broken, allowing the throttle to be stuck in Fast allow too much propane in for light off? It is dark now, work late tomorrow, so it may be Wednesday evening till I can get back at it.
You could shut the propane tank off and try a shot of starting fluid. Then you would know that you are not over fueling. It would fire on the starting fluid assuming spark and compression are good. Also might try shutting the tank off while running and then turn the tank on while cranking. It should fire before it over fuels if it in fact is flooding from to much LP.
That and you get basically no vacuum with the butterfly wide open? Do these really run at high idle and the solenoid pulls them down? Backassward if I ever saw it and to me very unsafe.
Yes it is rigged to pull the high idle down to low. I did find a source for those solenoids and he was local. http://www.fostertruck.com/fuel-shutdown-solenoid-1502-12c2u1b1s1.html I swapped in a new coil I had. Still starts great cold and just won't catch when warm. I have not swapped out condensers and points in years with everything being electronic. I can pull the condenser easily, but the points are part of a platform and do not come off. It is an Echlin assembly so I am hoping my Napa dealer can find a replacement. They struggle when it is not locatable by a car make and model year tho. Anyone recognize this set up? 4 cylinder Ford or GM? (I hope). .
I will try that tomorrow after I put the points back in. Lantraxco; Which butterfly are you referring to? Points gap? 35 thousandths?
It does not look electronic to me. Them are standard points. Remove just the second screw from the bottom and lift them of the post on the other end. The bottom screw is concentric and is used to adjust the points by pushing them either way in the slot.
Everything else I have is electronic, (not this) hence I am out of practice. I Know how to make the adjustment, but a guessing on the gap. .035"? If anyone recognized the assembly, or most importantly, what it is from, I would like to replace it. NAPA is unlikely going to be able to look it up under man lifts, or Wisconsin V-4. I am guessing it is from a Ford or GM 4 cyl car.
No promises, but, go to NAPA and ask to see the following: CS725A contacts AL70 Cap AL302 Rotor See if that helps any.
Thank YOU!! Stay tuned
There's a couple different distributors used in the Wisconsin V4's, if the numbers kshansen gave you are incorrect we'll have to do a little more research.
I was trying to find something in an Echlin Catalogue and this is the oly set that looked close the the original posters photo:
That was a pretty common setup in forklifts, tractors, industrial engines... probably WW2 jeep? LOL
The Points kshansen listed appear to be an exact match. The cap and rotor looked correct in the pictures, they come in this afternoon. Since there was no condenser # we found the Wisconsin V-4 listed in their book (I was surprised) and there were several engine models listed, We looked and the condensers listed and found one that appears to be an exact match. Is it the same value internally? don't know. I did notice that a lot of the parts were cross listed as Willys 4 cylinder parts.
Probably a Prestolite distributor, lots of the 4 cylinder engines used them. I'm guessing you got a VF4D or VH4D, the listing I found says point gap is .018-.022, but no guarantees.... I think there's very little variation in condensers electrically, should be okay.
Thank you gentlemen (all of you). Stay tuned.
The Condenser was Part # AL 869 With the new points and condenser installed, it started, when cold, even faster that it did before and audibly sounded smoother. They improved the running characteristics. Still would not start hot. I turned the LP off and even disconnected the tank to allow excess to bleed off. I shot starting fluid directly into the intake and it still would not start tho it did not bog down like it did when I did this with the LP still on. It gives you the impression it is ready to start, if you just let off the start switch, but it doesn't, even if you hold the starter on longer than usual. I do not have a vacuum gauge. So unscientifically, I put my hand over the intake inlet when cranking ( when hot ) and it sucked my hand down pretty tight. Enough to startle me. So I believe I have vacuum, maybe not optimal but it should pull any fuel down with ease. I took a couple extra pics just incase you see something I should check or change. From the starboard side you can see the inlet hose has been disconnected for starter fluid. I also have the fast idle solenoid out (the one that fell apart, I am not sure what the other is for unless one for LP and one for GAS) There are a couple relays, but they don't get too hot. Even though I have not been using gasoline, on the inlet, there is a diaphragm with something inline before it that says Wolffs on it and that has a wire feed and a ground. Could that be getting hot and shutting something off? Oh BTW, If it cools down for 30 minutes, it will start again.
I don't know what the bogging down means, so how about pulling one of those spark plug wires off and seeing what the spark looks like cold and hot? Maybe check that you have voltage on one side of the distibutor cold, and hot.
Does it have good power when running? Maybe gave it a compression test, cold and warm. Could it be worn and just not quite enough compression when warm? Maybe try a jumper wire from the positive battery to the positive side of the coil to insure it is feeding 12 volt to the points while the starter is turning. Don't leave the wire on after it starts if it does as it should drop to six when the starter is released to avoid burning the points.
It looks to me like there's more than one wire on the distributor terminal? Some of these engines had overhear shutdown tabs on the heads. If there's more than one wire, take off everything but the wire from the coil, try it. Hail Mary....
Lantraxco, the distributor only has one wire, did you mean coil? It is dark now, I will get to work tomorrow. BTW, When really cold, it stars instantly, 30 minutes of cooling will let it start, but not easily. It is strong when it does run.
Update. Still starts like a champ cold and not at all hot. Battery 12.95 volts resting 14.25 while running with alternator boost Coil 10.65 Volts at terminals cold and hot 11.2 while running Distributor post has one wire and it is connected to the neg Coil terminal (only wire to both) so it gives the same voltage readings as the coil. The Neg. Terminal of the coil is grounded to the distributor post if I made that confusing. Only wire to both. OK, I am not seeing the weak link (cause I am weak on electrical on cars/equipment) so do you still think more grounding and or a jumper to the positive coil terminal is warranted?
Huh. I can't quite read the coil does it have an internal resistor, I think so? You are losing a couple volts somewhere to the coil, might try the jumper and see if it makes a difference. Try one more voltage reading on the coil negative, not running. Shut the propane off, pull the distributor cap, rotate the engine by hand until you see the points close, voltage should go as close to zero as your meter can read. Don't rotate the engine manually with the distributor cap on, good way to lose some fingers if it decides to fire, seen it happen... the firing, not the loss of fingers, thank God. I don't recall the timing procedure on these old air cooled units, might be something to check. Also, what gap are you running the plugs at? Seems to me the LP gas engines ran a wider gap, but I won't swear to that. Anybody?
OK, Yes internal resistor, or at least no external unit. Haven't pulled the plugs nor do I know where to find timing marks or which cylinder is #1. I have a manual but it has next to nothing on the engine. I did add another 12 gauge ground from the coil to the block and I connected a 12 gauge jumper from the positive terminal on the battery to the coil. No hot start. I needed to move the machine and it runs great, hydraulics are great, well, good. There are two more electrical solenoids. One that looks like a 1966 Mustang starter solenoid (Post # 34) and that relays the juice from the battery to the coil and alternator and another on the starboard side of the motor seen in post #34, up on top of the motor. Could either of these be a culprit?
Not sure if this will help but here is a link to a manual on a V 4 Wisconsin. Around page 16 in the PDF file is information on distributor timing. http://www.wisconsinmotors.com:8080/wm/images/catalogs/wisconsin/VH4D_Repair.pdf And here is a link to another Wisconsin site that has some info on dual fuel systems: http://www.wisconsinmotors.com/product/4 Around page 60 or so there is mention of a high temperature safety switch if your engine has one of these I guessing it could be defective and killing the ignition on a warm/hot engine.
Great links Thank you ! It mentions the overheat switch in the manual first linked to, Says it is on the top of Cylinder #4. Which category of the PDF files did you find the page 60 on in the second link?
I went out to fire it up, and it wouldn't start....and it is cold. I removed the extra ground wire to the coil and then it fired up instantly. FWIW. I can't find any sensors attached to the cylinder heads, nothing attached at all. Of course It was 35 or so years old when I bought it, but for the first several hours of use it did start when hot. It has been messed with alot. Lots of disconnected wires all over the place. I looked at the timing directions. Looks like it would require some significant disassembly to visualize the flywheel, then you mark a vane with chalk when #1 is at TDC and try to time it with a tiny hold in the case. I doubt the timing has been messed with in many years so I am inclined to save that for last. Tomorrow I will pull plugs and see what they look like and if they will spark when hot.
New twist. It may not be heat that does it. I let it cool down. It started instantly, shut it down after 10-12 seconds and it would not restart. Granted it was not stone cold, and this motor does heat up quickly, but that short of time is not long enough for it to get very hot, just warm to the touch. I am stumped.
Gremlins.....
Correction. After cooling all night, It started instantly, shut it down after 20-25 seconds and it restarted instantly. Ran for 3 minutes and would not start after shut down. Fuel solenoid pulls to high idle, not the other way around. My mistake.
Have you been able to see if the plugs fire under compression when hot? We need to insure if its on the spark or the fuel side.
Would that be done by timing light or pulling a wire and seeing if it is sparking? I did pull the plugs, they look pristine. Gap was .018
Sounds right for propane. Pull a plug wire when hot and non-starting, check spark.
I maybe off but I had a old Bobcat 630 many years ago that had a 4 cylinder gas Wisconsin. I had very similar issues for a long time. It ended up that my Distributor was grounding out "sometimes". I change the points and the condenser first, then even changed the mounting plate. I found that it was a issue were the mounting plate was grounding out on the inside of the distributor housing. A lot of head scratching and around $200 and it was all better. Good luck!
Interesting Rob. The mounting plate sits directly on the machined shoulder with in the distributor body. What did you do to solve it? Replace the plate? Make a insulating barrier?
It was 20 plus years ago but what I remember was that in the end I replaced the whole distributor assembly (gear, shaft, housing, plate, points, condenser, cap). Of coarse getting the correct timing with the cam gear when you put the new distributor was a little tricky. Any small engine guy could do it for you if your not sure about doing it.
The Distributor swap is not the intimidating part, it is getting it timed. You mark the Fan AKA flywheel and time it to a tiny hole in the case, This part of the engine is under the turret so I would have to hold a mirror or something to do it. Thanks for the tip. I found the authorized Wisconsin service business in my area, Hate to go crazy tho, machine isn't worth all that much.
No insulation, the whole thing has to have a good ground for the points and condenser where they mount. Only insulated place is where the stud the wires hook to exits the housing. You can lose ground at any point where two pieces of metal are screwed or bolted together, oil, corrosion, gasket, etc. all can interfere with the electrical ground path. That's why I suggested checking voltage on the negative terminal of the coil as the points open and close, should read the same as the positive terminal with points open, go to zero with points closed. Any variance indicates a problem somewhere.
I pulled a plug and tried to start it after running it for 5 mins. It had spark. it did not seem strong, but I am used to looking at a spark on a HiPo V-8. I did look at it cold, and it seemed weak too, but it started instantly.
Did you check the spark on the plug with the plug out of the hole by grounding the plug with the wire connected. If so you are checking it without compression. Just pull the wire off the plug and check it by holding the wire end of the plug close to the plug terminal with the spark plug still in the machine and see if it sparks. If you get a spark it is firing while under compression in the cylinder. A weak spark with the plug out does not sound good to me.
The little bolt which fastens the points to the distributor plate; with the condenser connecting on the "head' end. If you remove the bolt and examine beneath the "package" there is a rigid "stalk" sticking up from the plate to support all this. THERE SHOULD BE; OR HAVE BEEN, A LITTLE THIN MICA INSULATOR STRADDLING THIS STALK. Brown, thin mica. This insulated the base arm of the condenser/points package from the plate, letting the movable portion of the actual points contact and ground, or complete the circuit as the points functioned. These things decay and flake off to not fully insulate. Most problem is an uninitiatd mechanic removing the old point set and not being aware of it, jerks it out and lost. Sticks in new points and no go at all. Depending on if all gone, no go-- to cracked, or split allowing some contact there. You may be getting a ground/circuit complete there before you actual points function. Just a possible.
I don't doubt the spark is weak and that the Rotor shaft stalk mica coating is on it's last legs. But why do they not keep it from starting cold and running well when started?
Try another coil. They can fail internally and give the issues you are seeing. AusDave
I was kind of thinking the same thing, I picked one up last night. Probably not install until tomorrow, work late today
Heat, vibration, etc. Replace the mica. (only place I ever found one was from another dist junked for other reasons) Try it... If no go... Then check the coil you have on it. If is has no internal resistor, get a NEW ECHLIN coil with built in resistor from NAPA. Put it on. (None of the pics show any external resistor in the visible hookup, therefore you need a coil with one.) Also, this air cooled engine does not throw off a lot of heat early. Most LP set ups pipe coolant water thru the vaporizer to vaporize the LP from liquid to vapor. Also, you mentioned you ran out of LP at last posting. You could have been down to only vapor in tank. Engines will start and run momentarily on a near empty tank of vapor. Then fail. Fill your tank... Replace the mica or temp tape the stalk. Then swap coil for known good with internal resistor. One of these should make a change.
Got a NAPA coil # IC14SB Yes I did get the tank filled to the brim (9.5 gallons in a 12 Gallon tank) Temp tape? Do you mean Temperature or temporary? I was wondering if there is a paint I can use to insulate the rotor stalk?
Temporary.. Plain black vinyl electrical tape. From plate up, over the top end, back down to plate. Punch a hole for the bolt. I have left several running with tape, but never knew how long it lasted. Probably until the points were changed again. Just for laughs, why don't you put on the full gas bottle- Try it -If runs, kill and retry. Same thing, was not gas. Insulate the points- try it - If runs, kill and retry. Same thing, was not gas supply or the insulation. Install the coil - Try it - If runs, kill and retry. It cranks and runs fine- Problem was one of these three.
Sorry to be so dense, do you mean to put the tape under the points assembly where it hangs on the pivot shaft? I tried to sketch an arrow where I think you are telling me to place the insulating tape. Am I way off? are you saying to place it everywhere the points assembly makes contact with the plate? . Or did you mean under the stationary part? I labeled the insulator under that part "B". It appears to be in good condition.
BTW, I filled the tank last Friday, did not affect the hot start at all.
No, that has the insulated terminal piece with the brown phenolic under it, riveted through, not much you can do there, except inspect visually and check the circuit electrically when hot.. the points have to have a good ground on the mounting plate.
Then I am confused as to where I am to insulate. The inside of the distributor body only allowing the thru bolt to com thru? I have read that paragraph over and over and can apply it to several locations.
I don't know, I think perhaps TD24 is talking about a different setup, but I could be wrong, have to wait and see if he sheds some light on it....
yeah, I will wait for his input, I need a better grasp before I start taping things up. Here are pics of the inside of the distributor body. The advance weights look rusty, well they are rusty, but move freely in and out. I shot some Boeshield on them last week but it seems to have already evaporated. .
It's posable that the rust in there is the root of your trouble! First the cam for the points looks awful,rusty rough,needs to be cleaned and polished,and just a light film of lube.There is a lot of rust in the bottom of the housing.If the pivot Pin for the points has corrosion,it may not have near the pressure to close the points properly to charge the coil.With the points off the plate,in your hand there should no resistance to the pivot pin,the point arm should swing freely.You can check for the points being insulated,with an ohm meter,when the points are open check to make sure there is no continuity from the arm to the base plate.set the points to .018 and make sure the contacts are clean and flat with each other.
You say you have at least some spark when it's hot and not starting, so it's not something shutting off the ignition current. You can test that spark by the distance it will jump to the plug installed in the head. Do you smell propane in the exhaust when it's not starting? The starting fluid was "inconclusive"/bogged down, how about dribbling a teaspoon of gas into the intake and see if it fires when hot?
Sorry... I am referring to the post-stub-riser or whatever mechanics outside of my area call it. Loosen the bolt holding the condenser wire, the points set spring and remove the screw holding the points set to the plate. Lift off the condenser wire and the points set. Now remove the bolt that held the condenser wire and spring. Lift off the metal covering the bolt was thru. Underneath it should be a thin brown piece of mica insulating the bolt and all it held from the post-stub-riser. (Brown if as old a dist as it seems to be-In a brand new dist it would be a white or clear plastic.) If it is there, and appears solid, no cracks, all one piece, you can handle in your hand without it shattering, then it is probably OK. If not, lay it aside. Install/replace it with a piece of tape to serve its same function. Punch a hole for the bolt. (Now as per Outasite... Sandpaper the lobes on the shaft clear of rust, then fine sand to polish. Then LIGHTLY oil the lobes - Or, place a little dab of grease in the corner of the block on the points that rubs the lobes. As the block wears down the grease will be drawn on the cam to lube till next replacement.) Reassemble the points and condenser (Both brand new out of the box I hope) Hope this makes sense as text.
Points and condenser are brand new. The pic is of the set up before I disassembled it. I will clean and lubricate weights, springs and rotor shaft. On the tape; Is my objective to make sure that the condenser wire is grounded to the assembly plate but insulated from the points spring (thus the points spring would not be grounded at all)? Or am I trying to ground the condenser wire to the points spring, but keep both insulated from the assembly plate? I know you are explaining this in detail, knowing my objective will help me not screw it up.
Best I can tell you is follow the directions and find the pieces of mica . Depending on what you do about it (Good and continue to use/Bad and removed) replace it with tape. I suppose the overall answer to your question is: Your objective is to replace the mica (if you had any) and if not, with tape TO INSULATE THAT POST IT IS ON from all that is fastened on, to or thru it. Do you have Skype on your computer? Do you have adequate "minutes" on cell of land line? If yes to either, PM me and I will arrange to show you these steps.
This is what I needed. I can do this. I already put the new points and condenser on. The Mica gasket was between the condenser ground and the post, but the screw connected it to the post so the mica wasn't truly insulating it.....and the symptoms existed then as they do now with the new points and condenser. Thank you.
OK... Re looked at your past 65 ... I have been referring to a bolt.. Where your dist has a screw. Older Prestolites had a bolt. (that is how tool truck sales made fortunes on the small "ignition" size wrenches). When you loosen that screw you can remove the condenser wire, the connecting metal strip atop the spring on the points, and that part of the points set. Some dist plates have a hole in the mounted post for the screw-Some had a forked or split post. On one you had to remove the bolt/screw to lift the threaded metal cover off- on the split/forked/slotted one you just pulled the whole package up and off. Someone chime in here and confirm or correct me, but in my limited experience the piece of mica straddled the post, just as the metal with the threads for your screw does, thereby insulating the whole post from the attached parts. However, after all the trials and non error during this experience, and the thing still will crank and run briefly, the problem is probably in you LP. Cold, cranks and runs briefly? Quits. Won't start? Sits a period of time and then will repeat this. A classic case of LP flowing, it is cold and refrigerates and ices the inside of the vaporizer and blocks any gas flow. Sits and thaws, re crank and repeat. Your pictures show a "Century" vaporizer. There is a push button on top, the primer. It is a sort of a reverse choke. It does not cut air like a choke, it shoot additional LP in when pressed, enriching the mix. Try this: crank it and as soon as it starts apply heat from a heat gun by blowing it over the vaporizer. This is to warm the vaporizer and prevent/hamper freeze up of its insides. If some success, higher/longer heat till it will continue to run a length of time. If this works, go buy you a new vaporizer; remove and replace the old. Its innards would probably look similar to the distributors. Easily kitted, but corrosion and stripped screws while opening up usually preclude repairing them.
I thought it ran fine until it was shut off, then would not restart. To me that eliminates freeze up unless it is freezing when shut off when there should be no flow. Perplexing to say the least.
Correct, It starts when cold everytime. It will continue to run strong until I shut it down. If I wait 30 minutes, it will start again, after it has cooled. Won't restart when hot. The primer, which activates by a switch won't help, in fact it bogs it down like the starting fluid did. By bogging, I means it sounds as if I am flooding it. The challenge will be to get the end of the points set and condenser wire not to ground out on the plate post thru the retaining screw.
By "flooding it" do you mean it sounds like the engine is hydrolocking? kinda like diesel detonation? rrr, rrr, rrr, clunk, slow r-r-r rrr, clunk, ? That sounds like it's firing and either the starter is extremely weak, or the timing is way too advanced, or something is seriously wrong with the engine mechanically, high compression from carbon buildup? When you try the primer or starting fluid, have you cranked the engine and THEN used the primer or a little shot of starting fluid? or did you use the primer/fluid and then crank it?
I have tried it both ways, same result. By by bogging it down I mean it slows the rotations down like the starter is straining. If i let let go of the switch the disengagement of the starter is a clunk, but if I hold it a few seconds longer it clears and the engine sounds like is about to start any moment, but just won't
You are correct on the no flow and the perplexing. Could he have leakage thru the lock off,some flow continues after key off and get enough to "stick" an old gummed up vap? That would be about as far out though as he has spark after shut down that will not crank it. but the same ignition (old and new) will crank it an run it well. STRANGE... Looks like the only solution right away is to connect a 500 gal skid tank of LP to it and crank and run till completely thru for the day. Like we used to run irrigation pumps. LOL LOL
I'm not sure if spark was checked under compression when warm by jumping the spark to the installed plug. Or maybe I missed it.
Put a different brand of spark plug in it and make sure it has the right ones in it according to the book. I've always had hell with Champions, not sure what you're running now.
When Hot, the spark will jump a distance of about 1/4" from the wire to the plug top. Actually was stronger spark than at the electrode so... I have had problems with Champion too so I bought the same plug in an NGK. First, I put on a brand new internal resistor coil. I used electrical tape to isolate the points and condenser from the post as shown in the pictures below, before, during and after. (there was no Mica present) Then I tried it and of course it started instantly when cold. Ran it for about 7 minutes and shut it down, waited about 30 seconds and......same as before, no start, sounds like it will any second, just wont catch and keep running. Then I checked the spark under compression as Old Iron suggested and it sparked, when hot, with the plug in from the wire to the plug, about a 1/4" inch. Then I Swapped in the NGK plugs which were the match for the champion plugs. Gapped at .030" per the manual posted way back. Still would not start (it was still hot).
The Plugs that were in the Machine when I bought it were Champion D21, The book says the NGK equivalent is AB-6 and that is what I put in (with no luck). In the Manual, when I looked up the electrode gap (.030") It mentions to use Champion D-16J. It is a preferred heat range. I am not sure why D21 was used. I have used heat range changes to maximize performance when the change in jets was available between two sizes, I never used a different range for cold vs. hot starting. Is it possible the incorrect heat range would cause this? I would not think so, but this is Propane, not Gasoline. Tomorrow, I will try the tablespoon of gasoline.
As I recall it was common to use a different heat range for propane, can't remember if it was hotter or colder. Found one reference to a Champion D9J on propane. Shouldn't affect starting though. Still don't see what the point is with the tape as that whole bracket is insulated from the points plate? Simply checking voltage at the distributor terminal as you rotate the engine by hand when hot with the coil wire removed will show if the points and all the insulators are working correctly. Should go to zero with the points closed and back up to around 12 volts after the points open.
After rereading all of your post,I am becoming convinced that your problem may be that the timing is the culprit.Most of us have heard a car or truck with the timing to far advanced,that will barely start.They just come up against the starter and stop when hot,but will fire right up when cold,and crank normally.Try putting a mark on the distributor,then loosen it and retard the timeing and give it a try!
With spark jumping 1/4" under compression we are insured we have spark when hot. Timing is certainly a consideration. Have you tried shutting the tank off and letting it run out of fuel. Then turning the tank on when cranking to avoid any chance of fuel leaking thru somehow. Might be worth sticking an amp meter on the starter to check amp draw when hot. Starters sometimes fail and draw lots of amps when hot and work fine when cold. Might be worth checking for the kick back issue.
Well, you certainly are getting lots of good advice here! The only thing missing is Willie saying to yank it out and put in a real engine (diesel). I sure hope you get it figured out because we're dying to know.
Another thing would be to eliminate the dual fuel switch temporarily to rule that out, or at least switch it over to gasoline and see if it does it on that side.
I don't think the Dual fuel switch is even connected. I have never run on gas and I believe the previous owner didn't either. I retarded the timing in 3 degree (approximately) increments up to about 10-12 degrees. Didn't help. Tho, the first 3 degrees got it closer to starting than ever before. It actually rumbled at super low rpm for a few seconds. I am going to get some replacement spark plug wires and if NAPA has them rotor and cap. Grasping at straws now. After that, I am going to have to call someone who is an expert on these to come over and figure it out. Some of the functions on the lift are either disconnected or not working, this problem tho, I can't live with.
As of today; Fill propane tank New Condenser and points, gapped @ .018" Isolated condenser and points from base plate Post. Clean and lubed cam lobe Retard timing, seems to run best approximately 3 degrees retarded from original setting New spark Plugs @.030" New Distributor cap and rotor New 7MM solid core wires insulated with heat wrap There is spark under compression when hot, Earlier put in new 10 W 30 Synthetic oil and new filter When cold, starts great. Runs strong and smoothly. When Hot, it still will not start, always sounds as tho it is just about to catch and run, but won't I need to find a local expert to take over. I will let you know when I find one and what happens. Thanks for all the tips and suggestions.
I see a few things going on with this machine I don't like. I see they have to propane vapourizor mounted right on the exhaust manifold for heating. Normally propane vapourizors are heated by engine coolant (which you don't have on a Wisconsin). Propane mixture has to be just right or it won't light. Lower limit is 2.4% propane, upper limit is 9.5% propane. Not much room for error. Be sure your propane components are in top shape, if you're not sure of their condition have them rebuilt or replaced. Other item is compression. Have you taken a compression test on this engine when it's hot? On propane the valves have a tendency to sink into the valve seats. This decreases the valve lash. As the valves warm up they expand and further decrease valve lash. I'm thinking maybe your valve lash is right on the edge and when cool it has just enough, but hot the valves are staying open a bit and compression is down enough that it won't fire. (Wisconsin's don't have much compression to begin with) (even less when they are old) It's possible. Why will it still run when hot but not start when hot? Speed. When it's running the pistons are moving so fast the compression doesn't have time to leak out so it builds up a "faults" compression almost. Cranking, the pistions are moving slower, the compression has more time to leak out, becomes even lower. personally.....a Wisconsin is the last engine in the world I put propane on......but don't let that ruin your day. It's just my opinion.
I'm with you OFF, propane conversions were really big in Texas on all kinds of tractors but I grew up at the end of it when diesels took over. I do know that sometimes propane systems would throw a fit but I was too young to learn any of the fixes. 2112, you had mentioned that you were going to spoon feed some gasoline to it. Can you rig up a temp tank to see how it runs on gasoline?
I will have to see what it would take to switch back. I forgot to do the tablespoon of fuel test, but it wouldn't start on starter fluid either. That and a compression test.
Update; Got home from work, and rather than fuss with anything, I just used the lift to get to a high spot to paint some trim. So I did not have to shimmy down the boom, I just let it run. Maybe 15 minutes. Normally, I just don't run it that long. I have not managed to get the throttle to shift to high idle speed, even with the new solenoid installed (must be a problem at the control panel). I just have functioned with "low" idle speed since getting the machine. It works with exception of moving the boom in and out would sure benefit having high idle. I have killed the engine trying to move the boom in and out too fast at low idle. Well, I could tell the unit was getting real hot as the heat billowed off the hood of the engine bay, I was about finished so I went ahead and moved the boom in faster than low idle can really handle and the engine became loaded and sounded as if it would die, I stopped and the engine just ran at this new "low" idle which I would guess to be 6-700 rpm. The previous low idle was probably 12-1400rpm (and when I manually move the solenoid to high idle, I would guess it is at about 2200 rpm). I never heard it run this slow before. I don't know how to force it into this new low idle, but here is the kicker. It starts when super hot! :usa It started hot 10 times in a row, but now it starts at this new super low idle speed . It kicks up to the old low idle speed if I use any hydraulics but won't drop back down.....unless I shut it off, at which time it starts again at the new super low idle speed. Up to this I have not been able to manually get the throttle to this low speed unless I hold it there. So It would seam I have been flooding it the whole time? That or there is something wacky in the "Choke" of the Century Vaporizing unit? It seams to be completely related to the controls of the fuel (LP). I just don't know where the fault in the system lies.
The fuel unit responds to vacuum, if the throttle butterfly is not closing down to idle they usually won't let gas through, though the primer should have solved that problem. Propane critters are just temperamental in my experience. Sounds like you may be on the right track! About the heat, could just be it's not moving enough air at the low rpms, or it could be a fuel mix and/or timing issue too.
I don't know if the heat is abnormal. I have only had liquid cooled motors, not even a VW bug. The fan sure seems to blow hard at the 1200 low idle speed and harder at high idle. I still have it retarded 2-3 degrees from the original setting which I would guess had been that way for many years. I know timing changes as things wear. I also recall that too much timing retard bumps exhaust temps real high. Even when it wasn't starting, it would suck my hand right down onto the intake, but that is not a vacuum gauge and it may not have been enough to change that butterfly. It is like something was stuck.....and magically became...."unstuck". The machine is 30+ years old. Getting the throttle solenoids to function correctly will really help with those times I need High idle to move that boom in and out. At the bucket there is a rabbit/turtle switch. when thrown, you hear a click inside the control panel of the turret, but no solenoid movement.
Putting your hand over the intake closes it off and creates the vacuum... the butterfly throttle valve in the carb creates vacuum by being nearly closed off at idle. Not really sure how this dual fuel setup works at the detail level. I'm wondering what is making the idle speed change when you activate a hydraulic function, is it possible it actually is your new throttle solenoid that just needs a linkage adjustment? It will have a governor, so the solenoid has to be connected up to the the governor linkage....
Will check the solenoid tomorrow, you may be right, I just can't get to fast idle. This is the control panel, UGH , all the wires are one color...white ;
Just noticed in the pictures the fuel rheostat only has only one wire connected
I think you're gonna need the manual for that one. Solenoids and rheostats don't go together, solenoids are either in or out. In between and they chatter and quickly burn up. That and the way the lines run on the panel, along with the picture of the variable pump almost leads me to believe that the rheostat may actually be for regulating the hydraulic flow? All the old trucks were that way, Kenworths we had used miles of white wire with little number tags on the end of the wire. Of course if you had to replace the crimped wire end, you had to cut off the tag to do it. Genius.
The solenoid dealer told me same thing. Also, just looking At the panel looks like you are correct on the rheostat too, it connects with the line to the boom hydraulics.
I notice there are two relays on the flywheel/fan housing, one looks like a starter relay, the other a horn relay. I'm guessing the small one would be for the choke solenoid, which looks like it's also wired to the propane primer, and the larger one of the two may be for the throttle solenoid.
Neither of the two big solenoids up top are doing anything. Nothing is actuating them to move. I don't know what was making the idle speed drop down to 6-700rpm. I used it again tonight, and it did it once but now it starts hot at what I used to believe was the low idle of 1200 ish. I am stumped, but happy it is at least allowing me to use the machine before summer is over. I used to turn it off after every movement cause I am painting. It is as if Letting it get nice and super hot that one time freed something up. Since it is not in the solenoid, then Maybe in the vaporizer? The small horn like relay? IDK