Opinions needed on rear main leak fix

[wrndln]

Sometime back I got an article from the Model "A" News that describes a simple rear main minor modification that supposedly eliminates or greatly reduces rear main oil leaks. The mod seems to make sense as the groove and drain hole would direct oil back to the pan and keep it from leaking out the rear main. I know that a little oil leakage is suppose to keep the wishbone ball lubed, but I can do that another way. I am pasting in two pictures of the article below. I took a picture of the top and one of the bottom of the article so the print was large enough to easily read. I am assembling an engine now and I could make the mod if it looks like it would do no harm.
Thanks for any constructive comment about the "fix" or if anyone had done the "fix".
Rusty Nelson

[Kurt in NJ]

It is a old time sleazy used car dealer fix --I was told about this fix by the same person that had me fill a trans and diff with sawdust to quiet them, and had me use newspaper behind bearing inserts to quiet a knock.---if it made the 60 miles to the auction and was still quiet I would get a bonus if it didn't go to arbitration after it was sold.

sometimes the slinger groove was filled with cotton waste or waterpump packing also ---they still leaked, but instead of a steady stream it was just a slow drip

[James Rogers]

I agree with Kurt, jury rigging. I have done this but not since I learned how to pour babbitt. This hole is hard to fix the next time the bearings are done. Not to say it can't be done reliably but, it does make for just one more problem to fix. If the leak is that bad you need to just have the bearings re-poured.

[Ron in Quincy]

Some 45 years ago, on two occasions, when breaking down engines, I found this modification had been done to the rear main bearing cap.
Some 30 years ago, a friend of mine was changing out the engine on his 30 Coupe with a new rebuilt "C" engine. He was going to rienstall the removed engine in a new speedster he was building. The removed engine had a bad rear main leak; I suggested we modify the rear main cap, as shown in the drawing posted, which I did.
This speedster has gone through 3 owners, the engine has never been changed, and today there is still no rear main leak.
As long as the babbit is good on the rear main cap, the thrust is ok, and proper clearance can be maintained, I believe this is an OK modification . I know others that have made this modification with good results.

Just my opinion,

Ron

[PC/SR]

I have seen a couple of those holes in old main caps. Better to spend the energy correctly installing the bearing.
I dont get why people use this or any of the other gimmicks that are around. A properly prepared and installed rear main will not leak more than a few drops. And you need a bit of seepage because that seepage is the only source of lubrication for the rear thrust face between the crank and main bearing. Try it if it makes you feel good but if the job is done right you don't need it.

[wrndln]

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Ron, thanks for the explanation you provided. The engine I am reassembling has new babbitt in it and I used Timesaver to lap in the crankshaft (the rods are next). The Timesaver made a huge difference in the bearing smoothness. All the high spots are gone after lapping the bearing in with course, medium, fine and extra fine Timesaver. I am a big fan of using Timesaver even though it takes a while to do it. After doing the Timesaver, the crank rotates so easy. My hope is it will make the time before bearing readjustment is needed a lot longer. I was just wondering if the rear main "fix" would provide extra assurance that I don't have a leak develop in the future as the rear bearing wears a little. I have the standard heavy flywheel I am going to use on the engine. I am NOT trying to fix and badly leaking rear main, just try to prevent oil leaks in the future.
Rusty Nelson

[Kohnke Rebabbitting]

If you try to do that in a cast cap, you will have a rear thrust all broke up in a pile!!