Engine/Transmission (1994 - 1998) Injection pump oil leak

[Kernel]

Noticed an oil leak at the back/bottom of my pump a long time ago and recently got a mirror and took a look. It seems to have been leaking for a while, lots of dirt stuck to it. Where could it be coming from, and is there any harm being done by having it leak other than getting worse? It doesn't leave any oil to be found on the ground.



I have also noticed not really a leak, but a touch of oil gleaming around the afc housing when a flashlight hits it. Its not running down the sides or anything. Is this normal with taking the afc housing on and off and sliding it around. Thanks for any help.



Scott

 

[Kernel]

Nobody? I don't know much when you get to this part of the pump. Is there a seal that is known to go bad, do I have to pull the pump, is it okay to keep running it like that? What I am looking at?



Scott

 

[JGK]

Clean it all off with engine degreaser and, once it's all dried off, take it for a short drive. Then get back in there with a flashlight and a mirror.



The AFC housing leak could simply be due to loose bolts. It's been a while since I've had mine off, but isn't there an o-ring seal on the housing? Maybe it's bad.



The lower oil leak could be from the oil supply or return lines to the pump.



-Jay

 

[Joe G.]

It may be a leak in the lifter gallery gasket blowing on the pump. I agree with Jay. Clean it up and watch where the oil is coming from.

 

[Kernel]

Which is the oil supply and return? Does anyone have a picture?



Scott

 

[Andy Redmond]

The pump oil supply comes from the oil rifle which has a tee below and behind the injection pump. A braided line runs behind the injection pump to a fitting between the pump and the tappet cover. A tsb is out if its a pre-96. . for a different fitting for the pump. You have the updated pump fitting if it would take a 17-19mm (3/4") wrench, to tighten/loosen the flare fitting in the injection pump.





The return is through the nose of the pump into the gear housing.



The other oil supply feeds the vacuum pump, which also returns through the gear housing.



The afc can be loose, a damaged "o-ring" gasket under the afc cover, the shut down lever coming out of the pump (fender side) can weep around its seal. The throttle shaft on the fender side or the engine side seal can weep or leak.



Several bolts on the governor housing can weep.



See the file attachments from Cummins Quickserve. .

 

[Andy Redmond]

Kernal:



See this other photo, number 13 from my first post /threads into the engine block side of the inj. pump below the fuel return line and the barrell/fuel lines. .



Does this help any?

 

[hsmith]

Had a small leak on mine after I did the governor lever adjustment. Removed the cover and reinstalled with a thin coat of silicone. Still clean.

 

[CumminsPower98]

I have a slight leak coming from around the throttle linkage shaft where it goes into the pump at the back. Does anyone know if this seal can be replaced simply by removing the linkage or is it more involved then that?

 

[Kernel]

Thanks for the pics, that's what I was looking for to find out where things are located on the pump. It gets hard trying to picture stuff when it's crammed up under everything. Is the seal where I believe the govenor housing? attaches to the back of the pump known for going bad? I am going to stop by the diesel injection shop here in town and have them take a look at it. I want to try and get my terms right.



Scott

 

[ProMac1K]

I have a slight leak coming from around the throttle linkage shaft where it goes into the pump at the back. Does anyone know if this seal can be replaced simply by removing the linkage or is it more involved then that?

Yep, as far as I know it's as simple as that. Take off the linkage, just pry the old one out and put the new one in. It's not a cheap seal, but it doesn't cost a huge amount either. Hope i'm thinking about the same seal. I've got the receipt for the seal but it doesn't say the name, just says o-ring if that's right, so i'm not sure which of the two seals on the housing it is. Thinking it's the one on the throttle linkage into the governor housing... .



Hope I didn't confuse you too much! :-laf

 

[Andy Redmond]

Kernal/Cummins98(98 see end of post):



Tmaas gave an excellent suggestion for the "cup seal" on the speed lever. I think he is referring to the throttle/speed lever shaft seal. .



A Bosch shop will want the bosch part no of your pump. Let me know the year of your truck and manual vs auto trans and i'll get you a part no for the a representative pump, then they can find the correct seal. $20-30



Since the pump lays on its side when mounted in a Dodge, the oil can drip down the shaft and then onto the governor housing making once suspect a leak at that point.



Clean everything really well, then find some talcum/baby or your wife's fu-fu power and a small suction bulb (a mini turkey baster, like you clean a baby's nose with when they are congested). Blow some powder along the shaft/seal are and other connection of which you suspect a leak, see where the power gums up and you have likely found your "seep. "



Cummins 98, yes if your careful. I have done this a couple of times on 180 pumps. An asst. of o-ring picks and pencil magnets are helpful.

If you are changing a head gasket, you have better access!



Good luck

Andy

 

[CumminsPower98]

My truck is a '98 as seen in the signature. The leak on mine is on the side away from the engine where all the linkage hooks up so the head being off would make no difference. It's not a bad leak at all, just enough to make the linkage dirty but I'm sure it will get worse and start dripping at some point. I have a set of o-ring picks so if I can find the right seal it sounds like it shouldn't be too hard. Thanks for the reply. Do I have to go directly to Bosch for the seal or Cummins or DC?

 

[ProMac1K]

I would say go to a Bosch service shop. At the time I did mine, I happened to be interning at one for a college course. I took my pump off and ran it on the test bench so the seal was pretty easy to install.



I can throw off some P/N's for 'ya on this shaft seal that I replaced but I can't specifically say which one it is. On my invoice receipt their is two numbers with the parts descriptions as O Ring and Ring, each with the quantity being 1 so it has to be one of these two. Of course it's possible none of these two numbers have anything to do with it, they could have forgot to add it to the invoice.



P/N 1420283006

Description: Ring

List Price: $20. 90



P/N 2410210014

Description: O-Ring

List Price: $12. 10



I think the higher-dollar ring was the big ring on the front of the pump that seals the connection between the front of the pump and the timing case. Also it's possible that these numbers are particular to this business where the parts were bought from, but i'm pretty sure it's a universal Bosch number since it was a Bosch brand part.



Kernel's and CumminsPower98's trucks should both have the 0402736913 pump I presume... . since they both have 96+ manual-equipped trucks.

 

[Kernel]

Andy,



Do you have pics of the backside of the pump. There are two screws on the back/middle of the pump. What is each one called? This is making me mad that I can't get a good look back there. The leak I think is coming from the top-right of the two. Not to be confused of the plate on top behind the afc housing.



Scott

 

[ProMac1K]

Scott,



I have pics of the backside of the pump. Are you talking about the Governor Housing screws or the Governor Lever Access plate screws on the Governor Housing?



Trever

 

[Kernel]

Governor housing screws. What is the screw that has a round head and tamper wire running through it? I got in there better and the leak seems to be either from that screw or the seam right above it. Wanted to take the fuel selonoid off and get in there but not having the time right now, got to go back into work... again.



Scott

 

[ProMac1K]

Scott,



Without actually seeing a P-pump that still has the tamper wires on it , I would say that is just a regular governor housing screw. Is the screw on the governor housing mounting area, one of the six screws that goes around the diameter of the housing, or is it one of the two on the back access plate of the pump? All the screws back there should be round. If possible, be more specific on the screw location. Either way, if the screw isn't damaged, you could try threading it out and rethreading it back in with a light coat of light-strength threadlocker, unless the gasket is bad, which would then of course need replacing or the screws retorqueing. Feel free to post back with more questions and keep us updated.



Trever

 

[Kernel]

The screw I am talking about is up under the selonoid bracket. There is one down lower about where the throttle linkage adjustment nut is which I believe is a housing bolt, from that bolt at about an 1 o'clock position above is another which has a rounded head that no wrench can go on and has a wire through it. Just above it is what I believe is where the top of the governor housing is. This is where my leak is I think, going the way gravity works and how it looks in a mirror with a flashlight. I haven't been able to take it apart to see if this is the top of the governor housing is or not. Wish I could be clearer than mud.



Scott

 

[ProMac1K]

Ok... .



Your description is fine. Bear with me though. I'm going to have to get a better picture of the pump tomorrow to help you out, I think. The pictures that i'm sorting through that I took are either of disassembly or are halfway distant shots on the test bench, nothing with enough detail, and I don't know the pump by heart yet. I'll maybe take a couple snaps of mine on my truck so I can get a better picture, since it has the solenoid on it and everything bolted up. So I plan to get back to you sometime tomorrow...



Trever