Distributor cap corrosion

DTM

Seaman Apprentice
Joined
Jul 20, 2008
Messages
38
Alpha 1 5.7L '86 Thunder bolt ignition - I replaced the ignition sensor in three months ago, cleaned cap and sprayed inside with WD40 and put a new gasket on the cap base. Yesterday took boat out to run in my new SE106 upper drive, have done 6 hrs over the last 2 weeks, so I have been using it. Motor ran good for 10 minutes then started to miss and run rough. Took cap off and found corrosion on terminals inside cap. Cleaned it and away she went, like a rocket.
My question is, why do they need a gasket when the distributor cap has a drain plug in the side that lets moisture in?
Previous to the ignition sensor fault, I had not had the cap off for 5 years, without any problems.
Just wondering why all of a sudden its corroding?
 

Grub54891

Vice Admiral
Joined
Jun 17, 2012
Messages
5,908
Re: Distributor cap corrosion

Its been corroding for 5 years,it finally got bad enought to cause issues,replace it!
 

DTM

Seaman Apprentice
Joined
Jul 20, 2008
Messages
38
Re: Distributor cap corrosion

Just to clarify, in January when I changed the sensor it wasn't corroded badly (this was after 5 yrs years without checking it). I cleaned and sprayed it ith WD40 and now after only 3 months it is badly corroded. I cleaned terminals inside with light sandpaper.
 

Grub54891

Vice Admiral
Joined
Jun 17, 2012
Messages
5,908
Re: Distributor cap corrosion

Ok,dont know why it corroded,wd have anything to do with it? My guess is yes,that should be dry under there. Anything in there bit air can make an electrical " channel" for wandering spark.
Grub
 
Top