I have a customer that has brought me his 54 Buick Special, he has just bought it and the transmission (Dynaflow) quit pulling shortly after he got it. I determined that the pump has a issue and we removed the trans to take a look.
Sure enough the pump is toast, but the failure is that the inner pump gear has machined itself into the backing plate for the pump. This has me concerned because I am not sure why this has happened and I obviously don't want it to happen again. The only thing I can figure is the the inner pump gear was shoved into the plate until it failed, and the only way I can come up with why this happened is that the crankshaft is moving back due to a failure with the crank bearings.
I have run across this before while working on other types of vehicles, but I have always been able to move the crank with a pry bar to conform the crank movement, but I cannot move the crank forwards or backwards at all, and I am using a big pry bar to try to get movement but cant. There is a "clean" spot on the crank right where it goes into the engine so my thinking was that the crank is moving and this is why there is a clean area, but the clean area could of also been caused by dirt or debris that is in this area.
Looking at the crankshaft set up in this engine it appears that the rear crank bearing has the "thrust sides" that keep this crank from moving.
For people that are familiar with this engine and or the Dynaflow is this common type of failure?
Here is a picture of the pump plate with bad wear from the inner pump gear.
Here is the pump gear itself
Here is a picture of the "clean area" on the crankshaft.
Any idea what this is?
Maybe a attempt to stop a leak from the converter hub?
It feels like epoxy or glue of some kind..
Thanks for any input anyone has on this issue.
James
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