Need a little help with Rear Main Leak

[Idaho Brett]

I'm resurrecting my family's Model A and the engine has a "bad" Rear Main Leak. I don't know the "full" history of the engine so I don't know if it has Babbitt Bearings or Insert Bearings.

My questions are ....... After dropping the Oil Pan, can I remove "just" the Rear Main Bearing Cap (by itself) to see what might be causing the leak and make sure the Rear Main Oil Drain Tube is not screwed in too far; as well as finding out which type of Bearings I have?

If so; is there anything I should look out for? I'm not familiar with Babbitt Poured Bearings.

Thanks

 

[Kurt in NJ]

Most likely it can be removed ---on a stock engine it can, but if it has been modified with counterweights it may not

the stock rear main bolts have a flat on the head of the bolt so it won't spin

there are other things that leak and seem like a rear main leak

read this---
http://antiqueenginerebuilding.com/REARMAINLEAK.html

 

[Gary Gregory]

The gasket between the flywheel housing and block was missing on my old engine...leaked a good amount at the end of the cam shaft. You'll need to pull the engine if thats the case.

 

[colin1928]

Most bad rear main leaks are due to excess bearing clearances
check for cracked Babbitt worn bearings thrust end play

 

[amodel25]

Before you drop the pan, check to see that the oil filler tube or cap is not plugged. If the engine cannot breath through the filler tube the crankcase pressure pushes oil past the rear main.

 

[jimvette59]

I had a problem when I had the filler tube breather pushed down to tight.