Distributor Main Shaft Wear Question

[Pat Bush]

Hello all --

I have a distributor main shaft that appears to be in very good shape except I have a tad of wear on the lower part of the shaft. The unworn section measures .490. The worn section is .4885 at its worst wear point. Most sections in contact with the bushing are .489. Is this within tolerance with a new lower bushing or am I gonna have to replace the main shaft too? Hate to do that -- it has a good tach drive section on it! Any advice would be helpful.

Thanks -

Pat

[Joe L.]

Re: Distributor Main Shaft Wear Question

Pat-----

I don't think that the amount of wear that you have will cause ANY problem, whatsoever.

[Clem Z.]

to help prevent this wear

i drill a .025 hole from the groove in the distributor housing where it goes thru the lifter oil gallery into the center of the bronze bushing to pressurize this area with oil.

[Pat Bush]

Re: to help prevent this wear

Clem -

This is a great idea! You wouldn't happen to have a picture or some measurements of where in terms of orientation the hole is drilled or maybe a little more description of where exactly to drill.... I am unclear which part of the housing to drill to get the full benefit of the lifter galley pressure.

Thanks -

Pat

[Clem Z.]

Re: to help prevent this wear

near the bottom of the distributor housing you will see 2 circular machined areas. these 2 areas are a machined to fit into a hole in the block that passes thru the passengers side lifter oil gallery. between these 2 machined areas there is a cast in recess and in this recess is where you drill the .025 hole thru the cast iron housing and into and thru the lower shaft bushing. you have to drill on a 45 degree angle starting near the bottom of the cast in recess and you will drill thru the lower bushing.

[Pat Bush]

Re: to help prevent this wear

Thanks Clem!

I am assuming the hole can be drilled at any point on the 360 degree circle as the entire area between the two machined components will be pressurized - yes? And I also assume you mean to drill a hole at the bottom-most machined ring at a 45 up into the center of the bushing... Correct? I only want to drill it one time, and right the first time :-)

Seems very straight forward and no loss in oil pressure given the tolerances.

Regards -

Pat