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unclemiltie
06-26-2006, 08:21 PM
Most of the Studes I have overhauled have been sticks. I have pulled several automatic equiped engines to part them out and have always found the flex plate to be in great shape. I am working on a new project and was pulling the 289 V8 with automatic this weekend. I separated the engine at the bell housing. When I got it out I noticed the torque converter was not necessary even with the back of the engine. After I pulled the converter off I saw multiple cracks around the converter. Once I took off the round thicker washer that holds the plate on the crank, I found that the plate was in multiple pieces. Besides multiple small pieces, I have two bigger pieces, one a little smaller than the retainer washer and the other the rest of it. The break looks like a roller coaster.

As I was pulling it I noticed the one front motor mount is broken and the rear ones look sad. I do not know if they are broken. I do not know if the front mount was driven with it broken or??

What can cause this? Is there something else I should be looking for?


The car has been sitting for 20 years in a garage. It was not started in 20 years and the engine is free. The previous owner parked it when it failed inspection for a bad exhaust pipe. He drove it into the garage.

Thanks

Milt

Roscomacaw
06-26-2006, 08:53 PM
This is usually the result of a misaligned bell housing. This is why we say that if an engine block gets fitted to a bell housing other than the one it came from the factory with - the "new" bell housing must be "dialed in" to assure it's being centered to the crankshaft.

If this isn't done, then the flex plate is forced to flex too much - to the point of breaking up! You have evidence of such in your hands there.[xx(]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

Mike Sal
06-26-2006, 10:59 PM
Is this Milt from St.Louis? If so, hello from the Saltsgavers. I just come across this forum the other night.

If not Milt from St. Louie, then yes, Mr. Biggs has the right answer. the bellhousing is not aligned with the engine and that caused the fracturing of the drive plate. You will have to dial it into alignment upon re-assembly to keep it from failing again.

I just pulled the engine from the old Green Lark that Cosco used to drive many years ago. Do you remember that car?
Mike Sal

imported_n/a
06-27-2006, 10:44 PM
My Grandpas' 63 Cruiser had the 289 replaced by the nearby Pontiac dealer(who also salvaged cars), with a used engine that came out of a tornado-damaged car. A year or two later, I was pulling the motor out to replace the cracked flex plate! I got one from the former Studebaker dealer where the car was purchased. I wonder now why they didn't say anything about realigning the block and trans before tightening it up. Maybe I'll track hose guys down and ask 'em!

Dwain G.
06-27-2006, 11:17 PM
And if you're lucky it may be out of alignment simply because one of the locating dowel pins is missing. When you're dealing with an unknown history it's best to check the runout of both the bellhousing face and the bore.
Also very important but seldom mentioned is protecting the new flex plate from any type of scratch that will surely become the start of a new crack. That means no lockwashers, and the rounded side, never the sharp side, of the reinforcement ring and any flatwashers (hardened preferably)are all that touches the flex plate.

Dwain G.