Distributor disaster

[philminotti]

I've had my 482 running on a test stand with a grand total of about 2 hours of run time.  Ran great.  FAST injection with a brand new FAST dual sync distributor.  After sitting for about 8 months, the engine is finally installed in my cobra.  The engine sat covered in my garage the whole time.  Well, upon trying to start it the first time after it was installed and obviously had no spark, I pulled the distributor cap...every metal surface was so corroded it looked like a rust colored chia pet.  I've never seen quite so much concentrated rust.

Could short start-stop intervals do this?  I'm perplexed.

phil

[machoneman]

Wow! Very odd indeed. I'd grab a shop light and take a close look at any/all unplated, unpainted or chromed engine compartment stuff from the underside next. Then, under the rear end. Finally, the under dash back-o-the-gauges, wiring, etc. If none of them show any similar rusty signs, it's a puzzle. 

Btw, do you have any drilled holes (yours or the cap's maker) in the ditzy cap to allow ionized air to escape, a common trick?

[fastback 427]

I had a buddy a while back with a blown BBC. He kept pulling it in and out of his shop all summer and fall. By the next spring the dizzy looked like you threw in a chunk of rusty steel wool. He pulled it apart cleaned it and sprayed it with wd-40 and hasn't had a problem since.

[philminotti]

As far as the rest of the engine and car, it almost all aluminum...the steel crank spacer looks normal, the water pump pulley boss (also steel) also looks fine. 
The distributor is a FAST unit, but I'm sure it's supplied by someone else, maybe MSD or Accel.  It doesn't have any holes drilled in it.  I spoke to the tech line at FAST and they didn't seem to think that's necessary.

[machoneman]

Actually MSD does recommend a shielded hole (see tech's reply) for ionization reasons. 

http://www.msdignition.com/forum/showthread.php?t=367

My mentors used to say one can't have a rusty part w/o moisture. Perhaps the cap drew in moisture after engine cool down. That or the all-aluminum nature of the engine and car may give a clue. Perhaps it's a galvanic reaction.  See reasons and causes as well as preventive steps one can take here:

http://en.wikipedia.org/wiki/Galvanic_corrosion#Royal_Navy_and_HMS_Alarm

   

[Barry_R]

Ionized air trapped inside the cap will significantly increase corrosion.  You need a vent of some sort, and they have a metallurgy issue if its rusting that badly.  I've seen similar stuff on MSD parts but not as dramatic nor as quickly.  Used to see it on factory stuff 20 years ago but they fixed the problem a long time ago.