I got a buddy that has had 2 MSD distributors wind up with moisture and rust underneath the cap within a year. Its a show car that doesn't drive in the rain and is always garage kept. Nothing else in the garage is damp and rusty and the kicker is that he has another car parked beside the one with the MSD, but this other car has an Mallory dist. No moisture or rust with the Mallory. Any idea what is causing this?

Every MSD I've had does that. They seem to run fine though, but it sure doesn't look good.

Jody

Actually, the only way he found this was when the car started popping and sputtering. He found that the timing changed from 14 to 2 degrees. He removed it, cleaned it up and then the car ran good again. Why would a MSD do that? I'll steer clear.

Got Vents?

now you're gonna have me pullin my cap and giving a look!

Could it be something to do with venting in the msd, along with a car that isn't heated uo (driven) much?

Mine was fine for the first 3yrs. (driven at least every week) Then one year it ended up sitting for other reasons for most of the year. Next thing I know it's got rust.:clonk: (NO vent in cap then)

I think the new MSD caps are vented. I had the same problem. My old cap was not vented. I bought a new cap because I needed one anyway and the best that I can remember with out checking, my new MSD cap is vented. Have you buddy look into a new vented cap at a local parts store.

Thanks guys.

Msd caps can be ordered with / without vent holes.. My fear for vents on the side is if you were to hit some water, somehow,, fan would throw it on the motor? On the vented dist? So I put my vents below the dist base , where the gromments fit. Only other thing I can think of where the moisture comes from is up the dist shaft? Moisture in motor? Nah.

MSD Vented caps have a cap on the vent it's not just an open hole.