Engine/Transmission (1994 - 1998) Oil leaks. What do I need?

[JHastings]

I have oil leaks up front and you know how hard it is to tell where they are coming from. Oil is kinda everywhere and all over the steering box. I have to pull the intercooler to clean it anyways so I am just going to replace everything I can at the same time. So I need to gather all my stuff before I start. What is there?



Vacuum pump seal? (WHere do I get the cheapest kit?)

Front Main Seal?

Front cover plate seal? (Do I just use silicone or is there a seal for that?)





Anything else?



TIA



Jamie

 

[CumminsPower98]

Common leak points in the area are timing cover and seal, vacuum pump to housing gasket (I now use silicone only here), vacuum pump seal and the gear housing to block gasket. Have you done the KDP yet? If not now is the time while you have the cover off fixing leaks. Also while in there you need to remove any gear case to block bolts you can, clean bolts and wholes using brake clean and air and reinstall with thread locker. All case and cover bolts torque to 18 ft. lbs. There are 5 gear case bolts inside the cover. Three of them (I think) are behind the cam gear. You can get to these by rotating the engine until one of the holes in the gear lines up with the bolt you are working on. The lowest bolt behind the gear can't be removed and you can't get a socket on there. I use a cheap 10mm wrench, which I did some grinding on to make thinner and also bend the end to tighten this bolt. I have done this to every truck I have done the KDP on. Mine was leaking between the gear case and block and for the longest time I fought the vacuum pump but this wasn't the only problem. Once I got all those bolts inside tight the leak was completely gone. The power steering pump and gear could also be leaking. The oil pan could be leaking too but the above are probably more common.

There is a gasket for the front cover. It comes from the factory with silicone on both sides. Most of the trucks I worked on I used the old gasket without any problem. My truck with 400k miles has the original gasket and it has been off a couple times. Some of them will tear though so it can't hurt to have one just in case. I think some guys put them back together with silicone only so its your call. You can get the vacuum pump seal kit from Cummins for under $10. Sorry I don't have the part number in front of me.

 

[JHastings]

KDP has been done, but no by me. If I understand you right though, I should take off the cover to the timing gear case and then R and R the bolts holding the gear case to the block? If everything is going to be off this thing I guess I might as well do this anyways.

Also, like you say I think it might be leaking between the vacuum pump and gear housing or it could be between the IP and the housing. Is this a common leak?

Do I need to remove my bumper to do all this?


Jamie

 

[Missouri Mule]

No you should not have to remove bumber. Gasket between IP and timing case I don't remember ever reading that one leaked.



With engine running you should be able to see vacuum pump (seal) leaking.

 

[CumminsPower98]

Its not likely that the injection pump is leaking where it mounts. This is sealed with a big o-ring and they don't often leak. If I were in your place I would clean everything real well and then keep an eye on things for a few days. If you do take the cover off then definitely R&R the bolts in there one at a time. They too can fall out and cause damage like the KDP and they are usually a little loose. Its not common for a bolt to fall out but it has happened. No bumper removal is necessary, you don't even need to remove the radiator to pull the cover. All I ever take out is the fan shroud.

 

[DPashko]

get some good degreaser, biosol works really good. . industrial strength, dont cut with water, spray everything down let sit and rinse with garden hose may have to do a couple times then drive for probably a week and check daily and it should give you a good idea of whats leaking. oh if your doing this in your driveway your gonna have a mess on your hands after rinsing... . so find somewhere you can make an oily mess

 

[VHolloway]

Try White Shepherd Stop Leak And Conitioner

Napa Sell It Best Stuff On The Market

A Lot Of The Guys Use It In The 24v Thats How I Learned About It:-{}

 

[JHenry]

My '98 12v was leaking oil all around the front of the engine, down to the front drive axle. Turns out it was the seal between the PS pump and the vacuum pump. I got the seal/repair kit from Gino's. JH