I found an odd oil leak on my 406. I've had more Chevy V8 cars than I can remember and never seen this before. I have oil leaking out of my distributor. It is an HEI I use the pickup in to trigger my MSD Digital 6 Plus. Oil is coming up the shaft and into the distributor and dripping out the rear of the distributor where the notch is on the back. It drips down on my tranny bell housing, runs down to the dust cover and drips from there, the same place my my valve cover leak was going. Both look like a main seal leak then. The leaks weren't obvious to see because of clean new oil and the new paint of the motor and tranny being new and shiny. You have to look close to see the leaks.

Now I may be the cause of this new leak because of a mod I did to get better oiling to the distributor and cam gears. I have a billet cam and run a Crane melonite gear they sold for billet cam use. Because they are both very hard surfaces, I decided to provide more oil to the gears. I took a jewelers triangle file and after plotting out where the gears would mesh together, I cut a small groove into the housing right above the distributor gear in the part of the housing the closes the oil passage. It now sprays oil directly on the contact point of the 2 gears.

Anyway, I now have to figure out how to stop the oil for coming all the way up the shaft. Stock it is supposed to go up the shaft to lube it, but not to come all the way up and out of the distributor. I'll have to devise some type of seal. I made a mod that will help my cam and distributor gears live longer but created a new issue. Just par for the course.

Mike

 

Is there a hole at the top of the shaft for the oil that comes up to run out and back down?

 

There is not a gasket, seal, silicone, "O" ring or RTV that would hold the oil back, spinning at six grand. It would have to be like a rear main seal but vertical.

I think maybe a phone call to the dizzy manufacture is in order. Ask them if they sell just the housing.

 

No there is not a hole for oil return.

Mike

 

I will probably machine the housing for a seal this coming winter. I don't need to replace the housing, I want to retain the oiling for the distributor and cam gears. I limit the rpm to 7500 so the fastest the distributor shaft turns is 3750 rpm. Most of the time it would turning 500 to 1750 rpm.

Mike

 

Sorry, I meant at the bottom like this. As I think about it it seems I remember someone putting second hole near the top to solve the same problem. That's a fuzzy memory though.

 

That makes more sense. I may try that, it just may work.

Mike

 

Beat me to it I was going to post my E-tech dizzy and composit gear.

 

Another thought. Cut a spiral in the distributor shaft so it is auguring the oil downward. Or a ring of downward angled cuts like the pattern on an oil seal.

 

I thought about the spiral cut too.

Mike