Crab dist shaft brg support breakage
 

My 59ab with 2 bolt crab started acting up. Points were oil soaked. Sent to Skip and he found the shaft bearing support by the rotor to be cracked. He replaced the shaft assembly and the plate assembly with a good bearing support. After a few miles car started running poorly only to find the new bearing support completely broken.
Any ideas on the oil soaked problem and 2x broken bearing support.
Thanks

Re: Crab dist shaft brg support breakage
 

Pretty abnormal for this to happen to a crab. I would suggest replacing the entire unit , housing , shaft assembly and point plate with support .....

Re: Crab dist shaft brg support breakage
 

A worn timing gear cover can cause issues as it can allow the cam to thrust forward too far

Re: Crab dist shaft brg support breakage
 

When originally sent to Skip,the rear bronze bushing was protruding slightly from the housing. Skip loctited into a flush position. After this short time use and is now broken that rear bushing is again protruding out approx .060 leaving the distributor key exposed approx .080.
I'm assuming this .060 is the clearance between the end of the cam and the distributor housing.

Leaning towards Bubba's suggestion but would like to figure out.

Re: Crab dist shaft brg support breakage
 

I have no experience with this, but was just thinking, would a 8ba timing gear set thrust the cam forward enough to cause this type of damage?

Re: Crab dist shaft brg support breakage
 

Using the original crank gear and an aftermarket aluminum cam gear.....not familiar with 8ba gear interchangeability.

Re: Crab dist shaft brg support breakage
 

Isn’t there an issue with the length of cam between engine years? I know that going from a crab style dizzy on my C69 engine toba helmet style dizzy, I need to add s spacer.

Re: Crab dist shaft brg support breakage
 

Any idea what year (range) the crank is out of? The cam timing gear has to match the crank timing gear, but the 59a and earlier are different than 8ba. I may be telling you what you already know, but the early timing sets thrust the cam toward the block. The later timing sets thrust the cam toward the forward surface of the timing cover. I agree with what your thinking, I would want to know what the root cause is here before you end up damaging another distributor.

Re: Crab dist shaft brg support breakage
 

I would bolt up another good distributor loosely then turn it over to check wobble and for run out on the slot /dog