Engine/Transmission (1994 - 1998) Another oil leak

[GAmes]

I have been chasing different oil leaks for the last 200k miles. With the help of TDR archives and other input I have found and fixed them all. This one I can't find. There is oil dripping from the bottom of the injector pump. The area around the oil line from the engine is dry. The front of the engine is dry as is the vacuum pump to pwr steer pump connection. The only wet area I can find is the inside studs that hold the pump to the case. The nuts are tight. Is there some other source than the injector pump gasket itself? I've tried putting dye in the oil and all the other tricks but can't find anything when it is idling. However, when on the road and towing it loses almost a quart of oil every 2000 miles, very messy when one drives 3 to 4 k a week.

 

[hsmith]

Hello GAmes! Isn't there an o-ring at the pump flange? Have not had mine off, but remember something about this. I will be watching to see what you find. BTW, just now passed 150k.

 

[GAmes]

I've heard that the pump has an o-ring, but if that is what is leaking I'll have to live with it. It looks like a really big job to pull the injection pump off, way more than I'm equipped to handle. Besides, I wouldn't want to accidently change my perfect pump timing.

 

[GAmes]

TTT. Any one with a theory??

 

[Kernel]

Hey Gary,



Yeah there is a seal that goes where the pump and the gear case come together that can become a problem area. A friend of mine has the same problem and he didn't want to have to pull the pump. Now it looks like the KDP hit him so he has an excuse to take it off and fix it. Could steam clean it and put some high-temp gasket maker around it?



Scott

 

[GAmes]

Hey Scott,



I've thought of that but can't figure out how to get the sealant to the mounting flange, I can't even see most of it. It looks like I'll be passing thru El Paso next week. I'll call you if it isn't too late.



Gary

 

[Kernel]

Call me whenever you come through. I'll be up, been working night shift 7p-7a and will be filling in for a company command so my hours are flexible for the time being.



Scott

 

[Andy Redmond]

Gary:



Your injection pump/to gear housing id is sealed by a o-ring that goes around the outside circumference of the nose of the injection pump. Sometimes the factory used locktite on the studs as they are not blind holes. They should have Locktite 242 applied to them when they are installed. If the front cover and pump gear were removed they could be cleaned and sealed from inside the gear housing. If this method is used becareful not gasket sealers etc. are allowed to goo and later fall into the gear housing then into the oil pan (fear piston cooling nozzle plugging).



The pump must be r&r'd to change the oring, you are close to half way there if you do the indepth above.



Look at the timing pin carefully, they ooze sometimes. Its easier to work on this if the vacuum pump/ps pump assy's are removed.



What about the gear housing to block area, this gasket can weep too?



Also the injection pump "speed lever" cup seal can weep with wear and shaft wear. (rear of pump where throttle linkage attaches).



It doesn't take much to make a terrible mess with our hd fan and road draft.



1 qt. in 2K if loaded and towing maybe normal oil consumption. Mine has used about 1 qt. in 3K when towing and 1/2 qt. unloaded driving since new (150K now).



Try some talcum powder in a "suction bulb" available at a pharmacy, to see where the leak starts to wet the powder. We have a rash of them from the birth of our daughter in all the "free" kits parents are given. :-laf



Good luck

Andy

 

[GAmes]

.



Also the injection pump "speed lever" cup seal can weep with wear and shaft wear. (rear of pump where throttle linkage attaches).



Andy

Bingo, I believe you got it. That was exactly what I was asking for, a new area to look at. I'd already looked at the timing pin and the gear cover, and didn't really thing there was enough oil around the injection pump mount. With 326+K on it I wouldn't be disappointed if the loss was normal consumption but there is a lot of oil blowing around the side of the engine and that is definitely a leak. There is a LOT of built up oil and road dust around that shaft. I don't normally shoot cleaner there when I clean the engine because I don't want to wash the lube out of the spring clips and the throttle rod ends and because of the brake master cylinder it is really hard to see. I will clean it up good tomorrow though and check it out.



Thanks Andy.



Oh, one more thing. Is there a fix for this, if it is in fact the throttle shaft?

 

[Andy Redmond]

A new seal, if the shaft isn't grooved badly. Likely doesn't require injection pump removal to change (just the seal), they are less than $25 at your flavor of Bosch service locations.



Good luck,

Andy

 

[GAmes]

Thanks again Andy, I cleaned the area up today and went for a short drive. Of course, since I am at home I can't see anything leaking. I'm headed for Ca next week, so will crawl under at the first fuel stop and look again.



Gary