Excessive oil under dist.cap
 

Has anyone experience excessive oil inside distributor cap and know why or how to control it? I run a msd billet dist that's about 8 yrs old. With a oil feed hole for gear and also run a vacuum pump with about 14" vac at idle. I have cleaned under the cap 2 weeks in a row
With same amount there. I run a crank trigger set up too. I have taken the distributor completely apart and seem tight with no play.
Keith

With a vacuum pump system, this is a little puzzling. We had oil in the distributor issues with a Mallory distributor years ago. That distributor had a large 1/4" feed hole into the shaft area. I tapped it and screwed a .060" restrictor in that hole. That took care of it. It was fine on the drag strip. Thousands of street miles could be a problem.

Pic of Badgto’s distributor

This distributor had never been used on the street. I have use this oil feed plug bef ore no issues.

There is a seal in the top of it. Could be your problem

The only thing I see at the top of the dist body is brass insert and the shaft rides on 2 thin brass washers. Does the seal have any rubber lip or anything to help seal?

I replaced one a while back. Yes it's a lip seal. I remember there was roller.bearing in that area to.

Does msd make a kit that you can buy?

Keith i have one that you can borrow if needed

Got the parts from a local speed shop that was a msd dealer. You could more than likely get them strait from msd.

Thanks for the help.

Bringing this subject back up because I have a stock Pontiac distributor in my race car that is leaking oil into the cap as well. Is there a seal in the stock distributor anywhere that could be going bad? I have a vacuum pump but it's still leaking.

I assume your block plug is drilled to oil the Dizzy and Cam gear, and if so to what size?

No, it's not drilled to oil the gear. Race only engine with BOP gear.

Big nose up lunches and no rear of pan baffle plate ,or baffle plate alone on the rear main cap studs can send a ton of oil right up into the Dizzy!