Engine/Transmission (1994 - 1998) Oil Leak

[LHastings]

Look out this morning and found oil under the left side of my truck I check it out it looks like it is coming from the vacuum pump seal between the pump and power steering pump. Is this seal replacable or do you have to buy a new pump?

Is it a dealer only pump $$$ or does cummins or a parts store like NAPA carries them? Also is there a danger of this seal blowing completely out before I can fix it? Last question how many bolts hold the pump to the gear housing and how hard they to get to?

 

[Dave M]

I've never done the seal replacement but I have seen many threads on it. Just search on "vacuum pump". I talked to Cummins West yesterday and they have a seal kit available for under $10... not sure whats in it (By the way cunmmins said this is a new kit that wasn't available before). I've heard the vacuum pump is very pricey and cummins carries it, but the power steering pump is about $100 at NAPA.



There were 2 bolts on my 97 vacuum pump to gear housing. Before you pull the vacuum pump rearward toward firewall, remove the sensor black electrical plug (I think its the temp sensor mounted to the block) which is directly behind the pump or you will break the sensor and/or the plug. I almost forgot this and the pump would not go back. Some cut the power pump lines and seperate it from the vacuum pump in the engine others pull it as an assembly together.



There is a web site that I would use if I had to do it that sells a seal kit and I think replacement pump or rebuild yours:



www.tricountymachine.com

phone 860-642-7033 John (a TDR member).



Here is a place with $60 seal kit: www.fixinrams.com This site describes the 3 different vacuum pumps used and good photos of the pumps and good info about the pumps. They will rebuild yours or sell you one.



I had a leak but it turned out to be vacuum pump to gear case gasket.



Others who have more direct experience will chime in I'm sure. Here is a good thread which contained photos on the disassemble and rebuild:



www.tdr1.com/forums/showthread.php?t=114409



Good luck,



Dave

 

[LHastings]

Thank Dave for the reply I sure will try the seal kit first and also looks like I'll be going down and buy some more tools for sure. You have to pull the drive off the shaft to replace the seal do you?

 

[LHastings]

Well check the price for a new pump Rocky Mountain Cummins wants $1200. 00 and Dodge wants $2000. 00. I found a seal kit at Diesel Tune for $25. 00 much better deal. I'll defiantly be putting a kit in.

 

[Dave M]

I don't know what it takes to put the seal kit in, since I never did it. I did some searching because I thought I might have to and gave you info I gleaned from my search. I don't know what tools it takes. Check out that last thread I gave you by user "A-BOMB" that had the pics of removal. Also a call to whoever you get the seal kit might get you more info. I think I would go with www.fixinsrams.com if I had to do it and talk to them. Sorry I can't offer more help than that.



Come on guys that have done this before... help this guy out!



I'm sure some others will jump in here and help you.



Good luck,



Dave

 

[hsmith]

Pull both as a unit, then separate them to replace seal. Replace gear housing gasket also. You will save time this way.

 

[LHastings]

Thanks for the reply. I looked at the pictures and it looks fairly simple. Diesel Tune here is a real top notch place he know his cummins. I have done a little diesel machanicing when I was going to college decades ago so I do have some mechanical ability. I just like to be prepared before I dive into a project. Now if the weather could get better, that garage is cold. When I get it replace I'll you all know how it went. The old saying if you can take it apart you can always use a hammer to put it back together :-laf

 

[GAmes]

I hope you haven't spent the $25 yet. The seal kit is sold by Cummins, Southern Plains for $6. 98. It is part # 4089742. It comes with the vacuum pump to case gasket, internal seals and very good instructions. If you aren't close to a Cummins place you could get the kit shipped to you. 817-640-6801.



The job wasn't very hard on my 2WD. I believe the instructions have you disconnect the power steering hoses. It is possible to remove the PS pump from the vac pump and set the PS pump on the frame, thus not having to bleed the PS system. The seals you have to replace are on the back of the vac pump.

 

[LHastings]

Thanks for the part number I'll get with Rocky Mountain Cummins and see if they can track down that part number.