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Author Topic: Oil Pump Leak  (Read 714 times)

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Offline Lewis

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Oil Pump Leak
« on: November 21, 2018, 11:33:01 AM »
Hello all.

I have a leak from one of the studs on the oil pump on a 1951 CJ3A. It does not appear to be coming from where the pump housing attaches to the motor. Does anybody have any idea if there is a gasket of some sort on this cover or any other ideas of what the fix may be? I still haven�t found an online diagram of the pump.

Any help is appreciated!

Offline 1955CJ-5

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Re: Oil Pump Leak
« Reply #1 on: November 21, 2018, 02:10:53 PM »
Here is a previous thread with some pictures.

http://www.cj3apage.com/cgi-bin/3Ayabb26/YaBB.pl?num=1384909830

There is a gasket in there. The thickness of the gasket sets the end play of the pump shaft.

The manual has some information on the oil pump in the L-134 engine section, paragraph D-62

Here is some more info...

http://www.cj3apage.com/cgi-bin/3Ayabb26/YaBB.pl?num=1384045882/11
« Last Edit: November 21, 2018, 02:19:26 PM by 1955CJ-5 »
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Offline athawk11

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Re: Oil Pump Leak
« Reply #2 on: November 21, 2018, 09:53:35 PM »
I can't remember for certain, but I think the studs that hold the pump to the block penetrate the oil galley.  If the oil appears to be coming directly from the stud/nut, you might want to pull the pump, remove the studs, clean the threads real good, add some Permatex 2 to the threads, then reinsert them.

If you decide you need to pull the pump, study up on how to re-index the pump prior to pulling it.



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1-1946 CJ2A

Offline Gunslinger

Re: Oil Pump Leak
« Reply #3 on: November 25, 2018, 09:21:43 AM »
I'll add here that if you do pull that pump take the time to find NOS gaskets for the pump cover.  There seems to be quite a bit of difference in the gasket thickness on new gaskets, the wrong thickness will cause your pump to lock up when it gets warm, then you risk breaking cam shaft teeth.  Midwest Military is a good source for NOS parts.  I found out the hard way....
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Offline Lewis

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Re: Oil Pump Leak
« Reply #4 on: January 03, 2019, 10:01:35 AM »
Thank you very much for the replies. This is all great info!

Offline Carls_jeep

Re: Oil Pump Leak
« Reply #5 on: January 05, 2019, 11:16:40 AM »
I suggest removing the pump and replacing both gaskets and checking the end shaft play to be sure it has the correct end play. Don't guess, use a dial indicator or feeler gauges to check it.
Resealing the studs is a good move.

BUT, when you remove the oil pump you will have to check the distributor timing because the distributor runs off the end of the pump shaft. Don't assume the timing is correct.

The dist is timed off the end of the pump shaft and if you don't get the gear back where it was on the cam then the dist. shaft will keep the pump from going all the way in. It may take two people to do the job, one to hold the rotor from turning and the other to keep trying the oil pump in different gear teeth matches to get it lined back up. The dist. shaft has an offset tang that goes into the lube pump gear.