68vitesse Posted March 25, 2021 Report Share Posted March 25, 2021 Spend the morning doing these tests on my Mk1 2L Vitesse, had compression tester for years but leak down from eBay. Leak down graduated high above 70%, moderate 40% to 70%, low 10% to 40% with the sparkplug adaptor fitted reads 90% so gauge reads low. No1 140PSI 40% air from oil filler No2 148PSI 40% air from oil filler. No3 140PSI 45% air from oil filler No4 135PSI 42% air from oil filler & Carb. No5 130 PSI 50% air from oil filler and carb No6 145PSI 40% air from oil filler. Heard nothing at exhaust pipe so either valves ok or pipe has a lot of small leaks. The plugs looked ok but No4 and 5 slightly different, when I had a cold miss fire which cleared after a few seconds it was cured by replacing the plugs in 4 and 5. The engine does over 800 miles to pint of oil, tests run on hot engine, air cleaner removed, throttle held open and carburettor pistons held lifted. No's 4 and 5 are the problem ones but do not understand why it would affect the spark plugs. Do not intend to strip engine but will test again after some more miles comments and any observations appreciated. Regards. Paul Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now