My '57 292 Y block has progressed from a slight drip, to a consistent drool while its running, coming from the oil pump. It cannot be driven like this. It uses the gerotor design and seems to just use a large o ring seal. The problem is, no one sells this seal that i can tell. Im hoping to just install the gasket while the punp is still on the engine, but i dont know if that is possible or not.
Check on the internet for an industrial rubber supply company. Most of them stock O-rings. You will need to supply them with this info, inner diameter, outer diameter, and depth of O-ring groove.
Contact melling directly, they may have part numbers for what you need. For the oring, find a bearing supply near you or a hydraulic hose place. Both I used to go to had a large rack on the counter with hundreds of orings. As Nick mentioned, you need to know what it takes. The same diameter oring will come in different thicknesses. Well he didn’t actually say that, but that’s why he wants you to measure the groove.
found a melling kit on ebay via part numbers, should work out fine. just needed part numbers in order to actually find it.
Make sure the block gasket is on correct. I ended up going to a new Melling spur gear style. Make sure the plunger on the bypass is free mine was sticking on the gerotor style.
If you suspect the O ring is leaking, you can remove the cover from the pump, remove the O ring, and look at it. Is it hard, cracked, damaged, or does it look good? Is it a round O ring, or is it square cut? If it's round, then it's going to be a standard size, you should be able to find a new one at one of the places mentioned. If it's square cut, then it could be more difficult to find.
It's still a good idea to remove the pump, take it apart, clean & check all the parts check the rotor(s?)-to-cover clearance for wear, make sure the relief plunger moves smoothly, then reassemble (possibly a bit of blue locktite on the cover bolts?) & put it back on the engine with new gasket on the body & new seal on the intake tube. Or, you could just install a new Mellings pump...
I’m with Jim , My experience with Mopar Gerotor pumps,,,,the o-ring will finally compress down to the shape of the groove . They start out round,,,,,but eventually mold themselves to the groove . Check the cover for flatness,,,,,,you might be able to help it some . I don’t understand why the rebuild kit came with all the parts but that ? Surely they sell a replacement o ring for this pump cover ? If all else fails,,,,you can make an o ring that will work . Tommy
The Jalopy Journal
