Thread: Re Crank Help

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I TOOK THE CRANK TO A MACHINE SHOP THE CORRECT READINGS ARE MAIN JOURNALS 2.438 INCH
AND ROD 2.098
IT SEEMS THE DIAL GAUGE WAS NOT CALIBRATED CORRECTLY

yeah, that looks better. Mains are 0.010", rods are standard.

THANK YOU TECHINSPECTOR Is there away you can tell me what the clearances should be

Although the serious engine builders will use inside and outside mics to measure the clearance, a person who only builds a motor once in a while and isn't used to using the same mics in the same ambient temperature shop day in and day out will probably fare better using plastigage. Get it at any parts house. Use a light film of oil on the journal and the bearing to prevent the plastigage from sticking to either and having to scrape it off and DO NOT rotate the crank with the plastigage in place. On a SBC, I shoot for 0.00225 to 0.00250 on the rods and 0.00275 to 0.00325 on the mains.

An additional thought, if the plastigage is tapered from one end to the other after being flattened on the rod journal, the indication is that either the journal was not ground squarely or the connecting rod is bent and not sitting squarely on the journal.
You can see the bent rod syndrome more clearly when you disassemble the motor to be rebuilt. The old bearing will not be worn the same way all the way across it.