DEJA VU ALL OVER AGAIN

JERSEYJOE

The last time I put a 401 together I got what I thought was a bad batch or connecting rod bearings. I assembled one tonight and I think it's happening again. Anyone else get a set of rod bearings with no slot to feed the inboard squirter? I know the factory bearings have the notch.It appears that the notch allows oil to reach the inboard side of the rod and squirt oil on the cylinder wall and the camshaft. Without the notch this will not happen. The bearings I pulled out of the box had no notch so out came the grinder and I carefully made the replacement bearings look like the OEM ones. Anyone else run into this?

AMX69PHATTY

Has been posted here, word is mfg quit adding the notch becuase "they" found it uneccissary. "Other makes have worked fine without the oil squirt notch all this time." Sure "they" did extensive research and AMC dyno testing to determine this, not. Guess the AMC engineers did it for no good reason, not. Sounds to me like a mfg cost cutting measure more than anything, "can we get away without having to put this notch in AMC rod brgs ?" Some say they are fine without, other put the notch in by hand as you have.

JERSEYJOE

Does this cause a pressure leak? Would seem so since the notch lines up with the feel hole on the crank and every revolution it will line up with the notch and squirt oil I am guessing on the cylinder wall or cam ???????.. If it squirts the cam which I think it does, it might explain a couple of the posts where I read that a new cam on a rebuilt motor wiped out in 200 miles. MC you thoughts please?????????

jeepsr4ever

You absolutely dont need oil squirter holes. You will get enough oil coming off the crank to lube the cylinder walls. You even get enough coming off the crank with a crank scraper. People dont realize how much oil is shooting from the sides of the rods.

dwg86

I think the clevite bearing still have the holes.

1980_Cj7

dwg86 wrote
I think the clevite bearing still have the holes.

No, they positively do not have the holes. I just redid a 401, twice. Neither set of Clevites had the holes.

On the 2nd rebuild, I discussed this with a very reputable engine builder. He said the exact same thing MC said above, you don't need the holes. He said he's observed an engine running where he could observe the bottom end somehow, and that there was oil flying everywhere. I got a set of bearings and made the holes anyhow, but when I took them to the builder, he said he'd use them if I wanted, but he wouldn't if it was his engine. At that point I deferred to his experience and went with no holes. So, I have a set of .020 over bearings here, brand new, with squirter holes, if anybody decides they want squirter holes.

JERSEYJOE

Well my bearings now have squirter notches on the upper shell only, and I an going to run it this way. Not that I don't agree with the experts but the stockers had them and they lasted a long time. I guess I will just use them. I think they also squirt at the camshaft and lube the lobes.