The 'E' Type Forum

When I took my newly restored 3.8 out for its first test drive I had the unfortunate experience of blowing out the core plug roughly behind the distributor. It flooded the cap and although I dried it all out, after about 4 weeks, she started misfiring. I discovered that the contacts inside had gone all powder like and green corrosion had taken hold. Again cleaned it all out and off we went. Now 12 months on from that the same again. Slight misfire and sure enough the same problem. I can get a new cap of course, and probably will, but wondered whether anyone else had experienced this issue. Clearly there are no rubber water caps on the screw in acorns. Hence the water ingress. Also, am I imagining it or is Vaseline the answer, or absolutely NOT the answer to coat the internal contacts with? Finally I had the car set up by someone who decided to put in the cap and on top of the terminal pegs a spare brass washer, as per the type fitted around the HT wire on the lead. I wonder whether that was a good idea or not. It seems to allow the HT lead to not make contact directly with the cap contact and if the spare washer floats around , as they have done, then it could reduce conductivity rather than enhance it? Answers on a postcard please!

Trim about 1cm off your leads to get to clean wire.
There is supposed to be a small brass washer in there. You slide it over the wire and then fan the wire out. This should improve contact. SOme people like to solder the wire here, I do not.
Buy a new cap.
Yes you can put any sort of grease you like in there.

thanks for that. I already have the brass washer on the leads but there was an additional one added that was free floating on top of the terminal peg in the cap. I will get a new cap and get some vaseline on it this time. I was wondering whether to fit some rubber boots over the acorns but not keen as not original look. thanks Andrew

Andrew, if you are dead against rubber boots (and l am sure l have seen them on 3.8s but couldn't swear to it) why not use a black gutter sealant instead of grease? It doesn't set (bit like dum dum).

From engine number RA2289/90, August 1963, rubber sleeves were fitted to the HT leads where they entered the distributor. The early distributor had a squared off appearance whereas later distributors had a rounded shape. Not sure if the early version is reproduced or not.

More info here: http://www.myetype.co.uk/forum/viewtopi ... 175#p44175

thank you again David. I will get a new distributor cap and get some vaseline in there. I don't plan on the core plug blowing out again!! will read that link now.