Brazed? rod journal...

[Hal Beatty]

I've been working on gas engines for 50 years now. Everything from Maytags to Merlins and a lot of stuff in between. But, I've never seen anything like this. I'm in the process of tearing down the stock 81A out of my '40. It was a good running engine with no knocks or other problems when I pulled the engine years ago. To put it mildly I was just a little surprised when I pulled the bearings off of the #3 rod journal and found this! Looks like the crank had a bad divot in it and someone brazed the hole up, smoothed it out, put some .002 undersize bearings in and ran it. I'm amazed it never caused any problems as it was my daily driver for a couple of years and I did not baby the motor. Note that the bearings are still in pretty good condition in spite of what the journal looks like. I think the crank is toast... there goes my hopes of a quick and cheap rebuild.

[Pete]

If the journals are out of round or undersize or both and if it mags ok, regrind it and put it together.

[J Franklin]

If it is not out of round give it a polish and use it. There is nothing wrong with that fix and it may even have been unnecessary.

[51 MERC-CT]

Surprised that someone went to that much trouble to fix something that did not need to be fixed. Just think of the heat required to do the braze.

[Hal Beatty]

Interesting replies... I may just clean it up and use it, if it mic's OK. But the thought of knowing there's been a huge gouge in the crank filled with brazing rod doesn't exactly give me the warm fuzzies. Got to get the crank out of the block and give it a better inspection.

[dude]

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My bearings should look that good...

[Bruce_MO]

Years ago, I bought an 8BA engine from a guy out of state after hearing it run over the phone. It was pretty cheap and I just wanted to get my car running. When I picked it up, it looked pretty good and did indeed sound good. He was a machinist and had built a nice test stand for it. Put it in my car and finally tried to start it 2 months after picking it up. Poured some water in the radiator...came back several hrs later and the radiator was way down. Pulled the plugs and found a major problem. Pulled one head and found that he had brazed a major crack from a valve seat down a cylinder wall about an inch, and had ground it down rather crudely and was running an undersize piston in that hole. Then I remembered that the test stand was never hooked up to any water! He only ran it for a minute or two when he showed it to me.

Long story short, I was screwed in a big way and paid $500 for a bunch of scrap. I couldn't believe that a moron would braze a cylinder wall and would think it would work. I now only deal with known or reputable engine rebuilders, and even then I've still had some issues.

[34pickup]

Years ago I took a 427 crank to an old crank grinder who did race engines and my crank had a pit in it similar but not as large as that one. I asked him how to fix it. He said he wouldn't because it was fine like that as it was just another place to help keep the rod journal supplied with oil. He said he had sent out a lot of cranks like that, just as long as its ground smooth it will not matter.