I have an oil leak at my vacuum pump. I went to Cummins for the seal betwwen the powersteering pump and vacuum pump. They told me I had to by a pump and that seals were not available.
I found out the seal is a 28x38x7 it is a metric seal. the numbers are in millimeters. I ended up with a 28x38x8 and it fit. The #8 is the thickness in millimeters. It is a touch thicker but works.
Unfortunately I still have an oil leak. I found that I have oil leaking not from the seal but from the adapter between the powersteering pump and vacuum pump. It is coming out of the seam where there is 2 nuts holding the adapter to the vacuum pump. Does anyone know if there is a gasket or o-ring or ?
I dont want to rip it apart and find out I have to wait a week on parts. HELP
Thanks Frosty

 

Frostie, check back in the old threads. I belive John Strenkowski sells the oil seal as well as the O-ring. Mine was leaking in the exact same place as you describe. I went to the hardware store and got a piece of gasket material. Cut it to fit the flange area and bolted it up. So far in 2 years it has not leaked since. I had to do it this way since the O-ring is an odd ball size and I couldnt find one at the time.

 

Check with http://www.intsealpack.com they sell the metric o-ring that is needed. Or you can contact John @
"John Strenkowski" jvssyn@rcn.com

 

Thanks,
Now if I can find the time. It sure is leaking, got to fix it soon.

 

Frostie
Mine has the same type leak. I wonder if Dodge has a TSB that might give the right "o" ring size. I used to have a link to Mopar TSBs but I have since lost it.

 

The problem with going thru Dodge is that they will want to sell you a new pump, not install or give you the option for the O-ring.

Shoot John an email, he has sold many kits for this and may be nice enough to give you the specs on the o-ring.

 

I E-mailed John, and he gave me a size--55x59x2 MM for the O-ring between the Powersteering pump and vacumm pump adapter. no one in town had one so I got the closest american size. a 138. I bought gasket material for a back up.
I disassembled it and found the american O-ring was too thick in diameter. so I made a gasket. No more leak. I hope it last as long as Montys has

 

well my gasket repair only lasted a few months. I guess I will need to buy the correct O-ring.

 

Dont feel bad, since I did mine the first time, I had to do it again. This time, I used Permatex Detroit Diesel sealant and a much better gasket. There are many sizes floating around right now for the correct seal and o-ring. This is due to chrysler possibly using 2 or 3 different sizes thru the years. If you get a rock solid measurement for the 1st gens. Please let us know.

 

Check out this thread on the TDR, I'm not sure if the first gens are the same as the second gens but Cummins has repair kits now.Vacuum Pump Thread

 

I found the correct o-ring. it is the 55x59x2 like I was told earlier.
its metric. 55 MM I.D. 59 MM O.D. 2MM thick.
I found a place to order it for me. So I got 5 of them
If anyone needs an O-ring for the vacuum pump adapter I have 4 more.
No more leaks

 

According to my '90 FSM, there are three o-rings. Two of the same size, and one which is larger. The two of the same size are used to seal the vacuum pump diaphragms to the housing, and the other is used to seal the power steering pump shaft to the housing. The two of the same size look like they can be changed by only removing the vacuum pumps, however the larger one will require removing the eccentric and drive gear from the steering pump shaft. Then there is the gasket that seals the housing to the engine gear cover.

Which o-ring are you guys talking about? My truck is leaking power steering fluid. I can see it on the bottom of the lower diaphragm. Since this is power steering fluid, is it safe to assume that this leak IS NOT coming from the larger o-ring that requires removing the eccentric and drive gear? My truck is at the injector pump shop, so I am unable to isolate the exact location of the leak.

Thanks.

 

If you have a power steering leak then none of the seals and o-rings that I was talking about is the problem.
Your correct about there being a seal that seals the drive collar shaft. it seals engine oil from leaking out, then there is a large o-ring, which also seals engine oil. it seals the aluminium adapter between the powersteering pump and vacuum pump. I have not been any farther into the pumps then that.

Frosty

 

Oh, ok. Thanks. Perhaps it's just a hose or something like that.

 

I suppose there is the chance that the shaft seal is leaking on the powersteering pump as well. Im sure there is 2 seals one on the adapter to the vacuum pump and one on the powersteering pump shaft.
Good luck with it.