Model b motor

dnkcurtis

dnkcurtis

Member
A friend of mine has a 31 pickup with a B motor, he has had it for 7-8 years and it seems to run fine.
Last week he noticed a knock sound near the back of the motor.
He finally dropped the pan thinking loose rod or some thing, only to find the splash pan in the oil pan has scraped strips and the crank lobes show it is hitting this pan.
The splash pan was down in position and not loose inside the oil pan.

Anyone ever run into this and may have a solution??
Thanks
DRC
 
For some unbenownst reason a previous owned welded the dipper tray to the oil pan in my '31 CCPU. Maybe it too was loose and rattling around?
 
When he pulled the oily pan he said it was snug and all the way down in the oil pan grooves, I’m suggesting that he feel the shims and see if ant are loose; all three lobs are hitting the tray, with The most noticeable scratch’s on the rear lob areA
 
The sound is very likely caused by loose flywheel bolts, not uncommon on 4 cylinder engines. The crank touching the dipper tray would not make a knocking sound may be the wrong tray? A's came with 2 or 3 different trays over the years, the B tray should have 4 large, maybe ", holes in the top, flat surface, not sure all B's had those?
 
I cannot imagine how the crankshaft is contacting the oil pan. Also, it something is scraping the oil pan, my guess is that it would make a horrible squeal, not a knock. I think Jim Brierley's notion that is a loose flywheel better fits a knocking sound.

My 1931 Coupe has a Model "A" oil pan fitted to a Model "B" engine, and no modifications were made to the dip tray for clearance. The clearance issue is with the larger "B" connecting rods and it occurs at the sides of the oil pan. The Model "A" oil pan must be dented to clear the rods as the Model "B" pan is.

The dip tray in the Model "B" pan is 0.13" lower like the 1931 Model "A" tray. Is the scrape mark on the side of the dip in the tray or on the bottom of the dip?
 
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Jim Brierley said:
The sound is very likely caused by loose flywheel bolts, not uncommon on 4 cylinder engines.
Click to expand...
How would one go about checking that?. I don't recall, an inspection cover on the bottom of the bell housing. Would hate to have to pull the engine just to check for the possibility of loose bolts.
 
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