Hello all, This is my first post an the forum and my first purchase of heavy equipment. My father has had old backho's and stuff but never any wheel loaders. I set out looking for a dozer but found what I think is a pretty good wheel loader, with a little TLC.. Mainly hydraulic hoses and the brakes need to be fixed. I just had a couple questions that I was wondering if anybody could answer about the machine. It is a 1965 and has a 453 Detroit for power but that is the extent of the knowledge I have on the machine, I can't seem to find any plates on in anywhere saying what model it is. I'm going to have to purchase a few parts and will need to know the model to do so. If anybody has any information it will be greatly appreciated. Thank you in advance Randy
It would help if you can find the serial number, should be stamped on the frame somewhere. sample would be3BG101 thru 3BG999 0r start with 4BG for a 55A, or 2CG101 thru 2CG999 or 3CG101 thru 3CG 101 thru 3CG101 thru 3CG999 for a 75A series II.
Thank you for the reply, I will take another walk on the frame for the serial number. The vehicle identification number on the papers is c4cg
Sorry I posted to quick and can't edit my post for some reason. The identification on my paper says c4cg945 if that mean's anything to you. Thank you Randy
Best I can tell machine probably is a 75A series III, or a late series II
Ok thank you very much.
Well i found the book to the loader and you are right.. It is a 75A series II. Now for a new question about a problem with the machine, on the front of the bell housing there is 2 small grey pumps and a bigger pump towards the top. On the centre pump around two of the bolts it is leaking a fair amount of fluid. its red fluid, I assume it is coming from inside the bell housing? what is the best way to fix this? should I take the pump right off and put a new gasket or can I take the bolts out and seal them. This machine is not going to be worked much lol, its mainly for grooming our race track and playing with so I don't need it to be perfect lol, but leaks do bug me. Thanks Randy
If I remember right that machine has a wet sump meaning that the housing is full of oil. In any case you should replace the gasket and put sealant on the bolt threads. Be careful when pulling the pump because if it is a wet sump you may get an oil bath.
If You are interested I have a various spare parts for Clark - Michigan
Thanks for that. I haven't had a chance to work on it much yet but I'll be in touch if I need something.
Just something to be aware of Randy , Make sure the back axle got steering stops to keep from over steering . if you turn the wheels too far , you can break the steering knuckles or pop out the large ball bearings that act as universals . I broke mine a few times before I figured out what was wrong . My wheels were steering too far as in a fork lift and popping out the ball bearings. Just something to keep in mind and check when you get a chance .
Nice looking old machine. And Detroit powered also. Great for us Detroit fans and easy to get engine parts for. Have fun with it.
Thank you for the heads up. She doesn't steer very sharp at all and I see where the stops are so I think I'm good there. Only problems I am having is getting fluid from the master cylinder for the brakes and a leak around one of the bolts in the pump on the back of the torque converter housing
Ya I was happy when I see the old Detroit in er, damn tough old motors.. We have had them in our boats in the past and they are a good motor, little leaky, alot noisy, but tough as nails. I changed all the fuel and air filters on er and she purrs like a kitten. Next for a oil change. Does the motor have a dry sump? I see the oil pump looks like its on the outside of the motor with lots of hoses and tanks lol.
Pump on the outside of engine is most likely for steering or something else. Follow the lines to see where they go. Don't think Detroits were ever built with "Dry Sumps" not that it would be impossible, but very unlikely!
I didn't think they made a dry sump either but this is a oil pump for sure. The hoses go right into the base pan. Ill see if i can get some pics later on. If its a oddball I would be the one to get it lol.
Here is a few pics of the pump and whats hooked to it.
Ok . The top pic is definitely a pump , trace back the pressure line and see where it goes. I suspect the loader has steering actuated ram on your steering drag link . What happens is when you turn the steering wheel it actuates a hydraulic valve down on the drag link helping you turn the wheels . It may not be like that but that's what my Michigan 55 was like . The second pic is your master cylinder attached to what looks like a vacuum tank . Does the loader have a compressor ? if not , looks like vacuum assists the brakes . if no vacuum you will not be able to bleed the brakes as there is nothing to push the master cylinder rod out . hope you understand what I'm talking about . Easy for me to type stuff that I've known about for 50 years but not so easy to understand if your just learning lol . Not really sure what the third pic is but it looks like another kind of vacuum tank . If no compressor , that the brakes are vacuum assisted .
I traced back to lines from the pump. The line from the pump goes to the canister in the second pic which has the master cylinder looking thing on it. The copper line that comes off of that goes to a oil pressure gauge. The other rubber hose that comes of the canister in the second pic goes into the canister in the third pic. Then out of that canister and back to the motor. The forth pic is just the opposite side of the canister in the second pic. On the bottom of the pump there is a short hose that goes into the bottom side of the base pan. The loader just had a single line master cylinder with nothing else on it. I have a couple of the old parts books for the loader but there no help, they just show the parts with a part number by them. I'll see if I can get a few more detailed pictures when it's daylight. I'll see if I can get a few more detailed pictures when it's daylight. I very much appreciate the help. Randy
That thing with BENDIX on it is a vacuum pump for the vacuum booster your master cylinder is mounted on is the second picture. The thing that looks like a recycled coffee can is a vacuum reservoir very similar to what Ford used on pick up trucks back many years ago. Did a quick GOOGLE on the vacuum pump and found this: http://http://www.powerbrake-drivetrain.com/bendix-type-convac-vacuum-pump-pb-2513134-r/ And this one: http://www.ebay.com/itm/NOS-Bendix-Convac-Vacuum-Pump-OEM-Ford-C8HZ-2A451-A-/400932408233
Thanks for the reply and help everyone. I guess I'll start looking there for my braking probables.
There are two of these 55s today in the HTFD/New Haven Craigslist.One is a Clark but same animal.One has a Cummins in it.Ron G
never had the pleasure of working on one of these systems but first thing I would want to see is it the pump was actually creating a vacuum, try taking the line off that goes to the coffee can canister and run engine should pull a good vacuum. The rest of the system should be very close to an old truck with a hydrovac brake booster. Been doing some searching online the best I found so far is this page: http://dave78chieftain.com/HydroVac_brakes.html Maybe someone else has better information on the system?
Thank you for the link, as soon as I get a chance I'm going to start working on it . Been getting ready for lobstering season so I haven't had a chance to work on it
Just noticed your location, NS! Took a couple vacations there many years back, one by motorcycle/sidecar. Cabot Trail was nice also had some fantastic scallops in Digby in a little restaurant right near the docks. Good luck with the old Michigan and if I can be of any help let me know!
OK, I have another question for the professionals lol, What should I use for transmission fluid in the loader? I find when its cold if I go into a bank all the wheels will spin but after a couple hours of use the wheels will no longer spin when I go into a bank. I am just wondering if I should have a different transmission fluid in it or not? I am currently using automotive transmission fluid from napa in it. Maybe its normal but I just want to check. Thanks in advance Randy
Not an authority on it but that could be normal after the transmission fluid heats up.Ron G
Oil in Clark Transmissions is determined by ambient temperature. -30 F and above Dexron (not Dexron II). -10 F and above 10W engine oil API Class SD or SE or Mil spec 2104B or C.or type C2 hydraulic trasmission oil. 30 F and above 30W engine oil same specs. Convertor shares oil with transmission.
converter function depends on engine coming up to correct stall speed. Cold oil in the converter will make up a little for that and not bypass due to leakage as much. As soon as oil warms up that advantage goes away. I would put in the correct oil then check the stall speed,especially with a 3 or 4/53, proper tune up can make quite a big difference.
Thank you for the reply's everyone. I will make sure to get the right transmission fluid for our temperature. I went through everything yesterday and changed all the fluids in the rear ends and the planetary's. Seems like a good old machine I just wanted to check on the transmission function from somebody that knew. Thanks again Randy
453 is not a dry sump that pump is a vacuum pump for your brakes. Detroits run sae 40 engine oil Api cf-2
You might check your clutch pressure with hot oil. Could have something Thats leaking as it gets hot in the clutch packs but I'm not sure the pressure would tell you
You can check for a slipping clutch by watching the drive shaft from the converter to the transmission. put the machine against the bank with the brakes locked down and hot oil, then rev up to full throttle in each gear slowly. If the wheels are not turning and the shaft is turning, whatever gear you are in has a slipping clutch, if the shaft is turning in all gears, the forward clutch is slipping, if you have good brakes you can do the test in one speed to see if reverse is slipping. Also check the clutch pressure in each gear at low idle, if one pressure is more then 5 PSI lower then the rest, that clutch is leaking internally. Listen to the engine as you increase RPM, if you notice a sudden jump up in RPM, you could have a slipping sprag in the reaction member support. The current Clark converters have the reaction member splined to the support shaft, the early ones have the reaction member mounted on a sprag which is like a bearing except that instead of rollers it has spring loaded cams that allow the reaction member to freewheel when torque isn't required but when you need the power the reaction member will lock down, when those cams get worn enough they will slip and you won't get the full torque multiplication so the machine will appear weak. The reaction member's job is to redirect oil coming out of the turbine that still has force back into the turbine, that is how the converter multiplies torque.
Oldseabee is the man. He knows his stuff..... Helped me on my 55b a while back. Did you used to be a clark mechanic or something oldseabee?
Worked for Clark 25 years. Started in '68 as laborer in factory, St Thomas, Ontario from that to production welder, to Engineering Lab building and field testing prototype machines to Loader/dozer lab in Benton Harbor,Mi.,to field service in South West US based in Ft. Worth,Tx, to Atlanta, Ga. covering loaders, rubber tired dozers, Euclid mine trucks, and forestry. Laid off in '92, went back to Navy for three months special work. 2 years road mechanic for Clark/VME dealer in Atlanta. Became National Service Manager for Bell Equipment USA. Also did 23 years in Navy, 5 years active, the rest reserve, first 4 years in guided missiles ('57/'61) the rest as mechanic in Navy Seabeas
My goodness,I always read your posts,one of my employers always had at at least one Michigan and for several years had two 175s plus a Trojan 4000.I thought that you might have been an active Navy seabee all that time but you sure know your stuff.Thanks for contributing here.Ron G
Thanks again very much for your help, I haven't had a chance to work on the old girl the last few days because for some reason it dropped to -10 here lol. The old machine should work good for what I bought it for, i'm only going to use it to maintain our motorcross track which is entirely made up of sand. It shouldn't be too hard of work for the old girl. I've been using a little B21 Kabota tractor so this will be a huge step up. Before that we had a 1950 odd Michigan loader, I think it is at 125. It was working ok but something happened to the rear end.
Wow awesome you don't find too many guys who know much about Clarks any more!
This might interest you, a little more detail about some of my past. The 70's were a great time to be in the engineering lab building prototype equip. in Canada the Govt. paid part of the R&D. I built the very first grapple for the new 667 skidder, we also built a mini skidder on tracks with hydrostatic drive, didn't work out very well, tracks were made of rubber blocks and kept falling off,no fun in a swamp. we built a tree harvester that would cut the tree and lay it on top of the machine grabbed by a cable pulled delimbing head that would delimb and top off then drop it into a bunk on the side of the machine, when it had enough to load a skidder would drop off the logs and go on, once the tree was grabbed by the delimber, the operator would be cutting the next one. it would do two trees a minute. Machine had two Cummins 378 V6 engines, one just for hydraulics and the other to run the transmission and steering, dual 30.5 tires on the front singles on back. Did field tests in North Saskatchewan and North Ontario, -40 degrees was tough working in. Also built the first 880 skidder, 903 Cummins, 275 size axles, Carco G80 winch, 13 1/2' tilting dozer blade. did field tests in Virginia pulling a chopper. Moved to Benton Harbor Michigan Eng. lab worked on first 675 loader. Set up one at Jasper,Al. Drummond Coal, came in on 9 tractor trailers.
I saw pics years ago of a loader with dual articulation,I thought that it was a 675.do you remember it and was it the one you helped develop?Impressive resume!Ron G
The 675 had a single articulation joint, twin 1710 Cummins engines with convertors feeding one transmission, 4 10 1/2" boom cylinders, boom and bucket weighed 20 tons each, bucket to boom pins over 200 lbs. each. Nice machine to work on, lots of room and every thing needed either a come along or the service truck crane to put it in place.
I Googled the Trojan 8000 and although I cannot find any pics yet the hits I did get made reference to dual articulation and I have the feeling that the machines were made back in the '60s so I will keep looking.Ron G
The 8000 Trojan did have dual articulation, There was a 6 ton center section with steer cylinders on each end. the claimed advantage was smaller turn radius and that in a full turn with a loaded bucket the center section acted as a counter weight give a higher tipping weight stability. it was an 8 yard machine with 480 HP either Detroit or Cummins engine. came out in 1966. 675 loader had 24 yard bucket or a 36 yard coal/chip bucket.
Sea bee I need to get with you on my 275b I have a delay in part of the controls. Its. Serial number is 425b-427 I think it's a 1974 but the bucket curl back has a delay long enough you can really rock it in and out to get a heaped load fast. I'm also thinking my hydraulic system accumulator is out because the machine seems to "slam" when you are booming up and kick the lever out of detent or are un curling the bucket it seems to slam what are your thoughts?
Sorry typo.... Can't rock it
A couple of things, 1 the hydraulic pump is 2 stage, both sections pumping give you 81 GPM at below 1500 RPM and1200 PSI, at 1800 PSI and above 1500 RPM the rear section goes into bypass so now you have36 GPM and at 2000 RPM and 2000 PSI you get 48.5 GPM. so if the pump dosn't bypass you have very high flow which will give you the slamming effect. That said, the main control valve is a split spool valve made by Husco, that means that one spool sends oil to the cylinder and the other one opens to send the return oil back to tank, this all is controlled by orfices so it happens all at once and the boom or bucket will move smoothly along with the proper oil flow, I have moved so some of my stuff is in storage, I'll have to go and dig it out for more specific info about how to do the testing.
A little off topic but years back we had an old 275 Michigan that was no longer needed at another plant and as at that time we were the central repair shop for the state it was parked at our quarry. It was used off and on as a spare machine until it developed a strange problem. As I recall the boom would go up and down fine but bucket would not roll back. That is unless you reved the engine up to high idle then bucket would move good at least till you tried putting a slight bit of down pressure on the cutting edge. As this was a machine we really did not need no one wanted to have us spend any time diagnosing it let alone spend a penny to fix it. So the machine was parked up on what was referred to as "Treasure Island". A couple years later upper management decided to send some surplus jewels to auction and this one was one of the ones going. As it had set for at least two years with batteries still in it there was no surprise they were dead as dead can be. But after hooking up jumpers to it for a bit that old Cummins started and ran like it was just parked over night. Also not surprising it still had the same hydraulic problem. As we needed a large machine to push and tow some of the other auction jewels around that day we kept it running. One surprising thing was after running most of the day the next morning those old batteries actually took and held a charge. It was taken to the auction site and continued to be used as a tow machine for the next couple weeks never failing to start. I did come up with a theory that I would have loved to check out but never got the chance to investigate as to what the problem was with the roll back. My theory was that one of the nuts(or what ever held the piston on the rams) had backed off allowing the piston to come off the ram and at low RPMs the oil would by-pass the piston through the hole in the center. However when engine was reved up enough the flow of oil was enough to push the piston back on the ram effectively sealing it again. As the surface area of the piston would be greater than that of the end of the rod the pressure would keep it in place until you happened to apply any down pressure then the piston would slip off the ram an the oil would bypass through the piston center hole. Shame as it would have been a simple thing to check just by unhooking a couple hoses on the cylinders and start engine with them poke in to a drain tube and try to roll back the bucket at idle watching to see which one the oil was by-passing through. There might be some other explanation but that is the one that seemed to make sense to me and it did bug me that I was not able to test it and fix it. Hope who ever did buy that one figured it out and fixed it would have been a good machine for a small two man gravel pit operation. It was a bit rough around the edges but was a strong working machine.
Makes sense to me, a less messy way to see which one is bad would be to take a piece of 3/8" pipe and use it like a stethoscope and listen to one of the cylinders while someone moves the bucket lever back and forth, you should be able to hear the piston slap. Also could be a bad port relief, try swapping the bucket hoses to see if the problem moves to the other direction which would sort of take the cylinders out of the picture and make the valve more likely, you didn't say if that loader was a "B" or IIIA, different valve set up.
I ran a 275 one summer loading a fleet of trucks and it had a 335 Cummins in it and was a very powerful machine.The reason that I am posting is that I was surprised that it did not have a Detroit in it as it seems that every other Michigan I had been around Detroit seemed to be the preferred power plant.Ron G
I think that Cummins was over the whole country was the majority, mainly what the local dealer preferred is what they pushed and some of the big Quarry customers like Vulcan Materials would spec the large machines with Cummins.
It is difficult to find fault with Cummins as much as the Detroit was liked for reliability.I am from a cold climate and the Detroit has a reputation to start if it will turn over as long as you have laughing gas to humor it a little and you often don't need that but no one wants to take a chance of it turning over twice in a row. They say the new Detroit 4 strokes are pretty good too.Ron G
I went ahead and bought the relief valaves for the pilot valves. Super cheap on minnpar so I figured what they heck. The machine will slam a lot harder if the engine is revved up while booming up say... I will note this the engine does bog down a lot and the machine Just doesn't seem to be very powerful when it comes to digging. Howerever it's very strong as far as push and travel speed but when you start booming or curling when in first gear digging pedal to the floor it really Boggs down. I thought it was a fuel issue. Put new filters on and also adjusted the throttle linkage to make sure it was getting full fuel and I still have the same issues. Seems now like it all makes sense I'll read my service manual but any tips you have sea bee would be great. Thanks again and sorry to hijack the op
As I mentioned in my earlier post, the hydraulic pump is 2 stage, one section should dump to tank at about 1800 PSI, if it doesn't you are trying to pump over 100 GPM at high pressure instead of 48 GPM which will load the engine a lot more and all that extra flow will cause things to slam and pop the reliefs. There are two styles, the early version had the control valve on top of the pump and would dump the front section at 1800 PSI, the later style had the control valve built into the center section and would dump the rear section of the pump, in either case there is a test port and a relief adjustment and another test port to monitor the section that is supposed to dump to see when or if it is dumping, machine has to be above 1500 RPM and above 1800 PSI to check the dumping point or if it is dumping at all. to do the test, bottom out the bucket rollback at low or just above then raise the RPM, the pressure on the dump should drop off at about 1500 RPM, if it doesn't drop off there is an internal problem. You can open it up and look for something obvious, (There have been stuck spools in these pumps.) or take the pump to a Tyrone hydraulic shop or any good shop.
Okay thanks sea bee. Thankfully I have a service manual too I'll diagnose this stuff next chance I get. I'm thinking though as bad as it Boggs the engine down and as hard as the slam is this has to be what's going on.
If in fact the pump is bad do you have a pump shop you recommend?
Motion&Flow Control 299 Bryant St., Denver, Colorado 80219 303-762-6527 They are Tyrone dealer, don't know any thing about them but seem to be pretty big in that area. By the way the relief valves in the pilot valve are port reliefs for shock loads, the main relief is in the big valve. Another caution, put a vaccumm pump on the hydraulic tank or drain it before messing around with the main valve or you may strike way more oil then you can get in a bucket.
Yeah i usually drain the tank first. At least lower than the pump if I'm working on the pumps but I suppose a vacuum tool for a radiator would work if you knew it would be a quick easy job. What would you say is the cause for delay in my controls? It has a delay for the bucket curl in. I'd say about 1 second delay
There are several choices, 1. air in the system can cause a delay, factory suggests do 3 full cycles of both boom and bucket at hi free idle to clear any air out of the cylinders, 2. anti void poppet stuck open in the main valve allowing either air or a vacuum into the system, 3. trash in one of the flow restrictors in one of the bucket spools. The first is easy, the others mean opening the main control valve. One other possibility is a faulty cap on the hydraulic tank, this is either a 7 PSI or 14 PSI pressure cap that helps squeeze air out of the oil mainly to prevent cavitation in the pump, air can collect in the higher end of the cylinders.
Hmm. It is only in the bucket curl back not curl out or boom up or down only in that one control
There is one restrictor in each spool for the bucket cylinder , the only thing I can think of to be sure is to open up the main valve and pull the spools out and check for a blockage in the restrictors. What I would do OFF BOOK would be to reverse the bucket hoses at the pilot valve to reverse the flow and maybe blow the trash out. Other wise you have to decide if it's worth all that work to save that second,or wait to see if it gets worse.
Okay just did some testing mine has the block deals on top of the pumps my main pump seems to be just on all the time type deal tested it out and I get a relief pressure around 2400 psi at 1800 plus engine rpm. Now the second pump which has a line the goes to the steering gear box and then another line goes and tees into the main pumps discharge line I am assuming it is the 2nd stage for the main hydraulics. At low rpm up until about 1500 rpm it will make pressure without moving the controls at 1500rpm roughly it will dump to no pressure. Now... If you roll the bucket back to the stops at low idle then hammer it we see no dump off of pressure it goes right on up to 2400 psi so both pumps feeding the main system show the same pressure above 1500 rpm but help we 1500 rpm the main 1st stage pump will not make any pressure unless you activate a lever. But the 2nd stage will. I'm going to get a video to clear this up a little and post a link
Here is a link to the video https://youtu.be/BQFu-Auk95A
The steering pump is a totaly different animal, it monitors flow and not pressure, low idle up to 1200 RPM has both sections providing full flow for steering at low RPM, 1200 to 1600 RPM the flow out of the rear pump section is gradually reduced and that flow is dumped back into the supply line to the main hydraulic valve assembly, at 1600 and above all the flow from the rear pump section is all diverted back to the supply line to the main hydraulic valve. To simplify all that, 1. At high RPM low pressure one section of the steering pump diverts to the main valve. 2. Both sections of the hydraulic pump and one section of the steer pump supply the main valve. 3. Low RPM low pressure, both sections of the steer pump supply the steer valve, both sections of the hydraulic pump supply the main valve. 4. High RPM high pressure, one section of steer pump supplies the main valve, one section of the hydraulic pump dumps back to the inlet side, so one section of the hydraulic pump and one section of the steer pump supply the main valve and the other section of the steer pump supplies the steer valve. 5. Low RPM high pressure both sections of the steer pump supply the steer valve, one section of the hydraulic pump supplies the main valve the other section dumps back to the inlet side.
There is only one test port on the main pump that I can find. But it still seems to be pumping way to much flow
But according to what you've said my steering pump is behaving properly. Just need to see if the main pump is dumping a section or not.
That test port on the valve on top of the hydraulic pump pressure should drop when the pump drops one section at about 1800 PSI.
That test port on the valve on top of the hydraulic pump pressure should drop when the pump drops one section at about 1800 PSI. Also some early machines were set up just to send the diverted oil either to the return to tank or back to the inlet of the pump. My last post was the way the system works when the pumps were plumbed to divert the dump oil from the steer pump to the main valve instead of dumping to tank return.
I should have added that you had to be above 1200 RPM for the main pump to dump one section
so assuming you watched my video the test port I pointed out(the very first one I pointed out) that one should at 1200 plus rpm and at 1800 psi it should drop down to minimal pressure? if that is correct then It is not dropping down it goes right up to 2400 psi at all rpm ranges.
Sounds like that's where your engine bogging down and hydraulics slamming is, the valve on top of the pump. Now you have to decide if you want to take it apart and have a look or buy a new one, like I said earlier stuck spool was a bit of a problem on those early pumps but you also have a pressure relief valve in there that dumps pressure that has built up in the spring area behind the control spool so the pressure on the other end of the spool can now shift against the spring and dump the front section of the pump. could also be trash in the high pressure poppet of the relief valve, one thing to try would be to back the adjustment screw off, be sure to count the turns so you can put it back in the right place then run the machine at high idle for a few seconds to blow the trash out of the high pressure poppet then reset it and see if the valve is dumping like it should. I like to do easy Sxxxt first then look inside to try to fix it but that would be me a little lazy and cheap. By the way FYI I was born and raised in Colorado, graduated Lakewood High School 1956.
Okay I'll try that! Sounds like some good solid advice as usual from you! How cool! The world is small..... That was a while before my time hah.... Born in 1990.
Did some more digging and found that only a very few B models were set up to divert steering pump oil to the main valve, mostly as a test. The C models were produced with the diverter system and some pump changes. the pumps you have work the way I said, the main thing was that they dumped the oil back to the inlet or to the return to tank line. I spent some time at Climax Moly mine running some temp tests on the hydraulic system on the 475 fleet they had at that time. Climax was a cold place in Jan.
I forgot to mention when you are revving up to clear trash out of the relief valve on the pump to bottom out the bucket roll back a couple of times to bump the pressure up. Dec. 1990 to May 1991 I was in the desert in Saudi Arabia as a mechanic with the Navy Seabees camping out in a ten man tent at night and during the day traveled around to different job sites in a 5 ton wrecker/service truck with another guy riding shotgun, no radio or cell phone to know what was going on or if we got into a fight no way to get help, but we did OK I was the equipment guy and my buddy was a truck mechanic.
Yeah the Henderson mine and climax are set to shutdown again I heard the other day. They are running all the new stuff now. Letourneu and cats but it's cold in leadville in January lol. But back to my pumps the upper pump in my video..... That fitting I pointed at is the one I should see a pressure drop off in yes?
That's the one, it should measure the pressure in the front section of the pump, pressure should climb until it reaches the 1800 PSI point or close then should drop off as the control spool shifts and the front section of the pump stops sending oil to the main valve. The oil from the front section of the pump is redirected back to the inlet side of the pump.
I may have missed a question I should have asked. Any chance somebody not knowing what they were doing set that relief valve on the pump to a higher level above the main relief in the main valve so it will never switch and drop the front section of the pump. Try backing off the relief on the pump 2 or 3 turns or even lower to make sure that it is set low enough to shift,if that is the case then set it back to 1800 PSI. I went back to your first post and seems like this machine is new to you, but I wasn't sure if the problem was already there or if it showed up after had been running it for some time. Just a reminder, you should be above 1200 RPM for it to shift.
alright well thanks to you I know where my problem is Im sure its a stuck spool or something is adjusted way wrong. hard telling what someone did to an old loader trying to make it do something. On my 55b someone took on of the regulator valve springs out of the housing for the transmission oil pressure no wonder all i had was 160 psi of clutch pressure lol put the right spring in a boom perfect pressures everywhere cooler in and out ect. Seabee what is your real name? feels like I should know it by now.
Bill Dempsey, I am too old and to many health problems to be working any place. I do enjoy helping folks out with some of the old machines. My theory is that Knowledge is wasted if it's not shared, I kept most of the manuals and notes I accumulated over the years both on Clark and Bell equipment out of South Africa, they built logging equipment and artic dump trucks, I was National Service Manager and then VP of Product Support for USA, 23 years at Clark both engineering and regional Service Manager, 9 years at Bell. I also go on a forestry forum and try to help out there. Keeps my mind active.
Just wondering if you ever got your 275 working right. Hope I haven't led you astray.
Bill, I pulled the plug on top of that upper pump this morning. The spool seems to be free. There is a small crack in what looks like some sort of relief washer attached to the spool but it appears to be very insignificant. I have not tried to back off the adjusting screw yet. Hydraulic oil cooler in the radiator cracked so the radiator is currently out of the machine being repaired. Maybe there is a connection between the hydraulic oil cooler being cracked and something with this relief deal?
As in maybe the cooler got cracked because of the excess flow?
Let me check to be sure, but if memory serves me and you can check the hose routing, the oil cooler in the bottom tank of the rad is the transmission oil cooler not the hydraulic oil cooler. The washer you mentioned is a check valve to seperate the high pressure rear pump oil from entering the low pressure front pump oil if it is cracked it will bypass and keep the pump from shifting properly, that could very well be your problem. Try minnpar.com to see if they have it, if not a good machinist could duplicate it, the flat surface is the sealing part. You should try to get the right part that would be ground and heat heat treated. You could try a silver solder repair but it would need to be lapped flat to get a perfect seal.
Ah okay it's a very small crack but possibly enought to.play with the pressure to screw it up. Mine has both coolers in the bottom of the rad. Lower one is transmission upper one is hydraulic.
item number 5 is the washer I am referring to
Bill, little update for ya, I adjusted the popett on to main pump a few turns back it bypasses! So we are all good. Man this is a completely different machine now. Hope things are well Bill thanks for your help
Glad to hear it. A long way around to get there but you also now have a working knowledge of how that pump works. My fault for not having you do that first. Some folks have to adjust what dont need it then cuss the machine for not working right.
yeah it wasnt until I sat down and really just read my service manual on the machine. It goes into great detail on how those pumps work. I figure someone was trying to make it faster or something but in turn just made it a dog. However now i like the machine a lot better its got POWER! Thanks for all your help and knowledge Bill. By the way what do you have for literature for the 275b's and 55b's?