My D6C had been acting like the governor was not always opening under load the last time I used it. Filters are not an issue. I started it today, after making a spacer to hold the hour meter shaft seal in which it kept pushing out, it would run full throttle for a few seconds and then die. It would then restart and I found I could jimmy the throttle and keep it going for a little while. I finally got it running steady and let it idle at half speed for 20-30 minutes and the throttle issue seemed to disappear. While getting it ready to put the skid pans on, it started leaking fuel from what I assume is the front seal drain tube. As I don't find a return line or external relief valve on this pump that could be plugged, is there something internal causing it to build up too much case pressure and either pushing seals out, or keeping it from running as that condition will do to a Roosa Master pump? I assume I may be in for pulling the pump off to reseal the front shaft.
Prolly the transfer pump.
To preface this, I have a Mitsubishi built 3306 with the sliding fuel metering collar pump instead of the Scrol pump. Finally had the time and pulled my injection pump off and removed the side plate. The front shaft seal on the fuel side was rolled out and the spring was off. I tried to find the pressure regulator valve but where I thought it should be in the bottom right corner behind the hand primer, there was a freeze plug installed in the hole. I finally found the valve on Cat Parts and it shows a valve and spring where I have a plug. As it is, I see no way for excess fuel pressure to be leaked off. I am going to remove the plug and replace it with the valve that should be there. Anyone have any ideas why this plug would have been installed in place of the valve?
I wouldn't do that. There is something else wrong and you don't want to shoot in the dark with a diesel fuel system. Engine explosions are dangerous and expensive. The pump you have is called a Sleeve Metering pump. I think the pressure build up inside is causing your engine speed issues. Take it to a fuel shop. Later Bob
Those sleeve metering pumps have a valve in them that constantly removes the air in the fuel and sends it back to the tank. I'm certainly not an expert on it, but I had trouble with one on a motor grader and I had the service manual on it and remember that the manual had a good description of how the system worked in it. Damn if I remember all of it though. Water in the system gives them major fits. Send the pumpguysc a PM, they can probably diagnose it.
Don, I don't think he has one on the D6. Cat only put return lines on installations were the fuel level could get below the pump and pick up air from line leaks. The later engines with the New Scroll pumps had return lines on any I have seen. That pump is lubed with fuel. Later Bob
I think you're gonna have to spend a little on that pump now. Probably just some rust in there seizing something after 8 years.
Lots of combinations of fuel flow with and without anti-syphon valves and constant bleed valves and priming pumps, but every one I see in the service manual shows a pressure relief valve installed where you apparently have the plug. Fuel pressure needs to be controlled to 25-32 psi. Only reason I can think of for installing the plug is someone trying to compensate for a worn out transfer pump.
That should have a small gear pump for a transfer pump with a relief valve under a plug on the pump. Sounds like the relief valve is stuck .
wrwtexan, I show that the plug is supposed to be there on this application. It is #17 in the diagram, hard to see but it's behind the cover on the bottom right. It has a circle around the head of the bolt. Is that the one you're talking about? 9S4180 plug and 4J7533 seal... #15 is a valve assembly (up at the top and slightly to the right with a t-handle), but if I remember right, that just drains the case.
Your #17 is the case drain plug. #15 is the manual vent valve. My understanding is the plug mentioned is under the cover, lower rh corner where the relief valve would be located. Could be correct if the relief valve is located on the transfer pump.
I pulled part numbers and ordered the pressure regulator valve (Classic Parts# 419-4716, ref# 1 and 2 illustrated on second internals page) for it which IS in the main casting lower right corner behind side plate and primer pump. The spring sets in a recess cut into the back of the plate. As it is now, there is nowhere for excess pressure to escape to other than leaking out of transfer pump and seals. Shame on me but I have had most everything apart on it and other than varnish, it is clean and rust free. I have dug two pools with it after pulling the governor housing off and resealing it, before it started pushing seals out. The transfer pump is loose so the plug very well may be an attempt to boost pressure. If so, it comes back off and gets a new set of gears and housing. These pumps are as simple as can be short of adjustment and calibration which I am not screwing with. The run and die problem reminds me of Roosa pumps where the damper ring is coming apart and plugging the outlet valve. Pressure buildup will shut them down like turning off a switch. Remove it and back in business (for a while). Any and all advice and info is greatly appreciated.
Relief valve flow routes through a passage back to the transfer pump suction. Be worth a check to see if the passage is clear.
I finally got my machine back together with the pressure regulator valve in place and started. It ran rough upon startup but seemed to clear out some at idle after warmup and completely at full throttle. Fuel pressure is at top of gauge After walking it for several hundred yards to a worksite, I made a hard turn and it loaded down then started missing. The problem turned out to be an open injector which I replaced with a used one from a local heavy equipment shop and it started and ran rough initially but cleared out again after warmup. Upon loading the machine though, it has no power and smokes badly. Unloaded throttle response is quick. I marked the cam before pump removal as I couldn't find a lockdown screw so I believe it is back in correct time plus it starts and runs well from low to high throttle. Anyone dealt with these symptoms before? It is the pump on d9gdon's post, and my local diesel shop doesn't know anything about Cat pumps.
that pump is pin timed with pin in it and 3/8 bolt thru flywheel housing into flywheel. make sure when putting bolt into flywheel it #1 and not #6 that's at tdc
Just got a new set of injectors and as Hatch and my parts source told me, I am going to retime the pump. I figured there was a lock pin someplace as I haven't ponied up the money for a manual yet. Was also told to remove slack from gear train before tightening. Will hopefully get it done this weekend and see if she is back to her old self again. I had been leaning towards out of time but it started and ran to good unloaded for me to think it was out enough to cause low power, but it did smoke like a freight train unlike before pump removal.
pull top of breather, and check valves on No 1 are loose and not rocking with your fingers, so you know No1 is on tdc firing stroke. pumps can be timed 180 out
I know that for a fact! Was a 3306. Started but did run like crap. Lucky it was being test run out of frame after a major rebuild so things were very easy to access. Pulled pump redid timing, this time for No.1!, and had it running again in maybe 15 minutes or so. Boss never knew we screwed up Back then the bosses we had would take that as a learning point and not a problem, now days not so sure.
After being told how to pin time the engine and injection pump, I retimed it and replaced the failed injector with a new one. It seemed to run better but was still underpowered and had a flutter at high throttle. I then replaced all the injectors and the flutter disapeared but underpower problem still exists. My parts supplier has tooling to work over pump so I guess that is my last option after averything else I have fixed or tried.
To restart my old thread, since fixing my injection pump, I've enlarged one pond, dug another, and picked up a few jobs with it and it runs good but not as I think it should. I run it on a fuel mix of 50/50 diesel/used engine oil and it won't roll black smoke at all anytime. It doesn't seem to have the power I think it should have and adjusting the ripper will load it. It will spin the tracks but looses many RPM to do so. I have watched 6D's and upon direction changes, will roll a nice cloud of black. A local heavy equipment shop owner says he can go through it, but I am expecting too much or is something likely wrong? I have been all through it and everything is free so is there something I'm missing or can fix myself? This pump is easy to work on compared to going through my Delphi CAV so don't think I'm an amateur screwing around where I don't belong. Adjustment specs are my only holdup.
first up, if turbos any good on any 3306/D333C in a D6 she won,t roll coal. they are only 140 hp, and don,t run much boost. The old D333 powered 76A at 120hp actually had more boost, they would puff some smoke till that big old schwitzer model D spooled up to speed. first checks for power, is boost at full load and TC stall, and then TC stall speed. Engine rack setting and governor full load balance point also come into it. Plus they were designed to fun on pure diesel, not a 50/50 dilution with less puha in its mix Is easy enough to open up the rack setting on a SMFS pump, but the pumping elements can be worn too giving lower cc,s of fuel. You WILL need the cat sleeve hight setting tool if you at all disturb the sleeve quadrants positions. Been 30 years since I last set one but remember it could be very 'delicate' to set up. Have got all the specs for a 69J smfs pump from mr cats bible, but would have to hunt them up. Both my tractors have scroll pumps, a much better pump. Cheers :drinkup
D6Merv. As our weather is starting to fair up and having a few projects in the waiting for it, I would like to see about turning the pump up some. I am running several of our turbo and non turbo farm tractors on the mix fuel and they will roll black smoke on it as well as straight fuel so I am thinking my 6 is not getting enough juice. My TD20B will smoke like a freight train on it but the 6 won't even smoke on direction change and reacceleration or heavy load. My limb riser is right in front of that little mitered stack and the exhaust hasn't even blackened the paint. I have watched 6D's running and they would give a nice puff starting off and some under load. I realize black is wasted fuel and I'm not looking for that. Rolling a little bit of smoke at least tells me she is getting enough fuel for rated power. Right now, adjusting the rippers or blade tilt will cause a significant RPM loss in first gear. Regarding the sleeve quadrant position, I assume you mean the barrel rotation location in relation to each other. I know not to screw with that without tooling, but what can I adjust to open up the rack setting? I have done this on SIMMS Minimec pumps and CAV's, but don't see what to adjust on this pump, nor does my diesel tech school book show it. I have considered doing a scroll pump conversion if its worth the expense if I can't get this pump turned up.
Have you tried a tank of pure # 2 Diesel fuel in it to see how it acts. Thats the first thing I would do for piece of mind if nothing else.
Fuel power density is definitely not the issue. I run mix in the summer and straight in the winter in all our tractors (Roosa and CAV pumps) and my 96' Ford Powerstroke and can't tell any difference in power or starting. The mixed fuel is actually closer to the old high sulfur diesel viscosity which these older pumps were designed to run on instead of this low sulfur thin as gasoline stuff now.
TD20B with the DT429 sent out smoke signals at the best of times ! Along with most other IH s ! 3306 has got 50% more cubic inches to start with than a 429 ! ok some specs for you. 69J2882 up tractors with sleeve metering pump. Fuel transfer pump pressure wants to be 30psi too; check this before anything else 1. 140hp @ 2000rpm. high idle is 2110rpm. rack setting is 3.75mm. But unless you have proper tools you can,t check this ! 2. turbo boost @ full load ie max hp; 2000rpm is 12.5"hg or about 6psi; said they don,t run much boost. TC stall is 8.5 "hg or about 4psi. 3 torque converter stall speed; or the poor mans dyno; and still the best check when combined with boost check is 1423rpm +-65rpm. You can set them up to the top end of specs; but my advice is that's all. All D6Cs had overheating problems that finally got fixed with the bigger trans oil cooler on later D6Ds sleeve metering fuel system is 'sort of' similar to American boschs psb pump; but has individual plungers for each cyl. and plunger doesn't rotate All later American 10k and early D6D 4x tractors had this smfs pump. Get yourself a service manuel. Fuel delivery; rack setting; can be increased easily enough. 1/4 turn of the screw can do wonders. But don,t overdo it. forget about the smoke, just go off how much boost you have [assuming turbo is good !!] and TCS. Also a good idea to check trans pressures too; before you get too carried away cheers M
Many thanks from my side of the world! I appreciate you taking the time dig up all the info. I will get a manual found and ordered. I just was thinking there might be an easy turn of a stop screw adjustment, but I will check all of the aspects you listed and hopefully rule out any major problems. The transfer pump housing is definitely worn but fuel pressure is at the top of the gauge. If it tests low though, I will either replace what's needed or maybe put a Holley electric pump on it with a regulator. As a side note, I had posted sometime back about her getting hot very quickly thinking I had a converter issue. On your recommendation, I pulled the radiator and found a layer of crap over the core blocking flow.:notworthy Cleaned that off and she runs nice and cool now!
A quick update on my low power issue. As stated before, blade tilt would load the engine excessively. Upon studying a diesel pump text book and Merv's info, I removed the cover over the torque limiter and moved one very thin shim from above the spring leaf to below it (closer to pump body) which gives a little more travel to limiting pin. There is noticeably less load down when tilting blade and neutral acceleration seems better. My fuel pressure is just above 30psi after the bypass valve finally opens (60 before) so fuel pressure doesn't seem to be a problem. Will put her in the dirt when our ground dries a little and see if I gave her a kick in the pants .