First of all my hyd. pump leaked oil into the crankcase after just overhauling the engine,fixed that. But when I was going to put the drain plug in I could smell diesel. Let it sit for a few days and noticed fuel leaking out of the oil pan.Disconnected fuel lines to the injectors,nothing changed. So the problem is in the pump. Removed the governor housing yesterday,not leaking on that side.So must be leaking out the front,I guess. Looked in service manual and parts book,don't understand were it could be leaking. there seems to be no seals on the cam that runs the injectors. How does fuel keep from getting into the engine since the cam runs in fuel? Also what is the best way to get the gear off the cam, only have a 2" hole to work thru.
What is your serial number kinda difficult to help w/o s/n.
S/N 1RJ00579, new scroll type pump.
possibly a transfer pump seal is out should be a weep hole on outside of pump but it may be plugged with dirt or a drain tube fastened to the weep hole is pinched.
The transfer pump mounts to the side of the injection pump and has no way to transfer into the engine.
Just what sort of motor is screwed into your D4C ?? as thats a fairly old banger, it should have a fuel pressure pump hooked into the Aux-drive, there should also be 3 drain down pipes possibly hanging towards the ground, 1 off the filter head 1 off the fuel transfer(pressure) pump and 1 off the injector pump, these stop Diesel/kerosene (depending what you run on) from getting into the engine, the filter head 1 is used when bleeding out after service, the other 2 are to save the engine from damage caused by fuel dilution. tctractors
the transfer pump will spill diesel in engine even though it is mounted to injection pump. that section of injection pump is engine oil lubed which drains back in crank case. most likely the transfer pump.
tctractors, it has a 3204, sounds like your describing a 3208 which does have drain lines coming off the pump,no lines on this one.
pw' I was thinking I might me a bit to Modern, I have just been involved in an engine repair (piston - liner -head) on an 88a D4 fitted with the 330 engine 4 1/2" bore, the engineering in the old bangers is first class, everything is strong and heavy as Hell, best of luck with your problem, a few pic's of it might be a treat? tctractors
It's more than likely the transfer pump. If you've got all your injection lines off and it's still putting fuel into your engine then that would be the first place to go. Try taking it off and hook the lines up and push the plunger by hand a few times and see what happens. Worst case scenario, and its been a while since I've taken one apart so maybe somebody can correct me if im wrong. Aren't there individual seals for each plunger inside the injection pump body? Your fuel goes into the the side of the pump on that block, that feeds the plungers. The cam is on the bottom of the plungers that rotates and pumps fuel and that's lubricated by engine oil. So if your fuel seals go bad then that'll let the fuel down into the oil side of the injection pump? Like I said I've only done a hand full of those and that was a while ago so correct me if I'm wrong
If someone could show me were these fuel seals are I'd like to see them. Fuel comes from the tank to t.pump, to filter, to side of inj.pump body, return line come out of top of inj.pump body.I've taken the T pump off, looked no seals. T.pump runs off the inj. pump cam, individual cyl. pumps run of the same cam. Parts book shows no seals,repair manual shows no seals. Were is it sealed to keep it from going into the oil?
I agree, something is missing. I'm looking at a 3204 parts book and I don't see any seal device between the camshaft and the accessory drive housing nor how it is coupled. I suspect there is a seal that the nose of the cam fits in but I'll be danged if I can find it. As shown it is open to the front gear drive train which leads to the sump. Assuming there is a seal for the pump camshaft the transfer pump would still be on the open side and have access to drain to the sump if it is leaking.
On a new scroll pump, there is no seal on the camshaft to keep fuel out of the engine. The lower portion of the injection pump is oil lubricated, and the fuel surrounds the barrel/plunger assemblies on the upper portion. The fuel is sealed off from the oil on the bottom of the bbl and plunger assemblys. There is a machined washer that sits between the bbl/plunger assys and the pump housing. Since there is no seal there, seperation of oil and fuel rely on flat machined surfaces. That is one place the fuel can enter. The transfer pump can be at fault also. The check valve next to the rod that rides on the cam is the barrier.
OK, I follow that....thanks. Just not very clear in the parts book (D3 with 45V17160-up engine.
I just joined, but it appears the forum will not let me post a new thread, however will let me do a reply. So; hope it doesn't irritate someone to hijack a thread? Related topic anyway. I'm on land in middle TN, fixing to start growing good food, (exceptionally good food) of the kind talked about at, http://levels.westonaprice.org/farm-a-ranch/461-nutrient-dense-food-high-brix-farming-gardening.html along with what's being called carbon sequestering, biochar production, in the process we have a bunch of forest land to clean up. (old farm land that grew up in trees) Various portions of usable level and sloping spots on around 130 acres on a mountain side. In '03 I bought a 1960 D4 7U4.... strait shift, 24V electric start, has the large bulky injector pump like the older pony engine started machines. Worn out in several ways. I rebuilt the tracks, rebuilt engine with sleeves rings and bearings, modified the hydraulics to make it power tilt. But in spite of the engine work it's always been very low on power and takes a lot of starter fluid mist to get it going. But have managed to use it for a few things, couple jobs for hire but otherwise just a little logging and land clearing for myself, although it's just barely usable and to do any pushing it has to run on flywheel power. (engine bogs down with the slightest load, requiring excessive clutch use) 2 years ago I put a turbo from a military multifuel engine on it, running upside down because it was rusty and didn't want to come apart and reverse it's orientation. It gave it a major power boost and I was able to get about 3 hours of real work out of it. And then discovered I'd lost 3 gallons of engine oil through the turbo. Got the turbo right side up so it would quit dumping oil, and no power again. (evidently it was the oil mist making the power) But I need to use it again for some land clearing so I pulled it back down to the shop recently, (running worse than ever, too weak to drive itself very good) pulled the injectors out, reconnected them to their lines, cranked the engine, and I'm getting weak streams of fuel squirting out, instead of the spray mist that I assume it should be. So there's the problem I suppose, right? I had previously replaced the non functioning fuel pressure gauge, found fuel pressure weak, put an electric pump in parallel with the mechanical one and brought it up some, (7.5 psi when electric pump is turned on, up to over 10 with engine running) replaced fuel filter, replaced all the injectors, and got one new injector pump piston/cyl unit just to see what that did. (one of those 4 units that are clamped on top the pump) Nothing did much for the power except the turbo when it was dumping engine oil mist through the intake. So I'm trying to figure out what to do next. So I guess the best ?'s I can think of is; what is the fuel pressure supposed to be? and does the fuel pump supply the pressure to the injector nozzles or do the little rod pistons in the units on the distribution head do that job? I have thought of trying to supply the intake with an oil/fuel mist to duplicate what the upside down turbo was doing, but that would not be fixing the problem, just side stepping it. Any suggestions appreciated.
Which machine is it? The 7U production ended in 1959. The D4C with D330 engine started in 1960. Transfer pump fuel pressure max is typically 15 psi. 7.5 to 10 psi is adequate to feed the injector pumps which build the high pressure. It is the function of the governor to control the fuel supply via the injection pump rack. Doesn't sound like yours is working. Engines with turbo's have different rack setting then normally asperated engines.
Well guys I finally took the inj. pump off the machine , seems everyone is telling me it's the transfer pump, took it apart the check valve on the piston side is ok, and the only way the fuel can get in the oil side is thru the rod that runs against the cam lobe to push the piston, which has no seal, just highly machined surfaces I suppose to provide a seal. There is always fuel present in this area. So I hooked the fuel lines up to the tranfer pump,left it overnight,no leaking on the rod. So I hooked the lines to the fitting on the upper portion of the inj. pump,were it would normally feed fuel the the individual inj. plungers, left for a few minutes and there is fuel leaking out the front of the pump, were oil should be draining back into the engine. 3rdGenDslWrench mentioned something about seals on the inj. plungers that run against the cam. As far as I know there are none. I kind of like to fix things myself as I do all the maintainance on everything I own. Does anyone have anything to help me do this. reubenT Welcome aboard. That's how I got in, and I'm sure most others as well. Wish I could help you but that's a little old for me. Although I have worked on some 17A's,D7's. Sound like you have inj. pump problems. Perhaps the screens in the nozzles are clogged up. The tranfer pump only supplys fuel to the pump and boosts it from there to the nozzles.
I'm with LonestarCobra and his description.....basically there are no seals....just highly (hopefully) machined part fits. If you have leaks then something isn't seating of fitting right or is worn. The more I look into these 3204's, the less I like them.
Ok, thanks for putting up with a dual discussion for a bit. The 1960 date was someone's guess so, so it's actually '59 or earlier. The serial is 7U43662. I have had the governor apart and all I found was a minor bushing missing causing very slight looseness in one shaft, which I fixed, (spare part from a much older but identical injector unit that a friend gave me) otherwise it looked in good shape, seems to operate properly. But as far as adjustment of the rack, or the fuel injection rate, I have no idea. I've just always made sure to get it back the way it was after having it apart. I'm a reasonably capable mechanic but haven't worked on diesels much. I think I remember hearing about a different fuel setting for turbo engines, I just stuck the turbo on to see what would happen, figured as weak as it was running it sure couldn't hurt anything. If it'll run decent without it I'll remove it. I'll play with it some more tomorrow. My uncle in WI has an older pony engine start D4, otherwise the engine looks identical to mine. It had sat for many years unused, and probably still sitting there. But when I was there in the early 90's once we pull started it with a skidder, (pony engine didn't work and main clutch stuck) it started cold with the first turnover and run good and strong. I know mine should run like that, but never has, acts more like a serious wimp.
A governor looking right is not the same as working right.....you need to get someone familiar with these old machines to have a look. These engines are usually pretty good performers for what they are. Got three 7U models myself. Yes, that serial number is a 1959 model near last built.
Pwking I wish I could help you out a little further than this but I'm kind of at a whoa till I can get back into the shop and find some books on that engine. As far as taking the pump and the plungers out you need to Pin the pump on #1 TDC. And if you are going to remove the plungers inside of the pump when you put them back you need the Rack Centering Tool so all the plungers will put out the same amount of fuel. Now I'm not sure if the Rack center tool is the same but you should be able to take a 3/8 bolt, cut the head off and use the shoulder (no threads....the smooth part) to pin the pump on #1 TDC.
OK; what I found today kind of helps clear up the previous mystery. Evidently the injector screens were clogging at about the same time I made the transition on the turbo. Cleaning the injectors made a big difference, now it runs on 3 cylinders quite strong. Injector no 3, which is the new one, is still not putting out enough fuel to ignite except an occasional hit, will have to do something more with it. It also tells me the turbo pressure was giving it the extra power, not the engine oil mist it was putting out. Which I'm glad for. It doesn't have to be perfect, all I need is enough power to get some work done, and looks like we're close to having it. Even though it should run strong without the turbo. Without it when dropping it down to an idle it dies real easy, but with it it will idle slow without killing too easy. By the way, those little forks on top the injector pump cam lifters are adjustable with lock nuts, do they adjust the amount of fuel delivered?
Do not touch the little forks!!!
Those fork adjustments are used to set the timing of the injector pumps.....don't mess with them unless you are resetting/checking the timing. Fuel control is handled by the torque spring and rack which is controlled by the governor and spring. You need to get yourself the proper manuals for the D315 engine. Rack settings are listed in the Rack Setting Manual for Caterpillar engines. There are many combinations of governor groups, springs and torque springs for various engine arrangements. Fiddling with adjustment will not obtain satisfactory results and can lead to a damaged engine.
Old M. IS EXACTLY RIGHT.. I just figured I say it in simpler terms.. DO NOT TOUCH!! IF the lift pump is not leaking.."at a stand still" and your still getting fuel in the oil.. It {almost} has to be the pumping units itself..and seeing you replaced[cleaned] the injectors..and "the new one" isnt fireing.. My prognosis[guess] would be "that cylinder" is the problem.. You could move "that injector" to another cylinder and see if it FIRES..if so..you found your pump problem..
Guess it was bound to happen....these two threads appear to have run together.....unless I missed simething the D47U is not the one with the "fuel in oil" problem.
Yes your right OM. 3rd Gen, I don't intend to pull the the individual pumps apart, as that would do me no good, it would have to be leaking past the lifter assembly that runs against the cam. I just can't understand why all the sudden it's leaking into the oil, but I've never been that far into the pump before.