I was told that the intake needs to be removed and that it's about 2.5 hours for a ASE mechanic to perform the task. I was quoted $350 for the job from Firestone using the NGK platinum tipped plugs.
35
.28-.35 is good
.32 to.35
235
ngk plugs are .31 to .35
I have a 1979 Evinrude 35 Hp Model 35902A and it has Champion L77SC4 Plugs in it and it runs great. Hope this helps
My neighbor and I did mine in 45min. The parts were $35 at napa. America's Service Station was going to chrage me $565.99. No that is not a typo!
the gap is 35 assuming you have the 2.0 4 liter
The gap for NGK-R CR9E PLUGS 31-35
service manual says .31 to.35 for ngk plugs.
I need to know the year to be exact, but 35 thousand is a pretty common spark plug gap setting on a Chevy 350!
I never had to space them, refer the book by the spark-plugs.(I think it's 35 thousands.-----.0035") Actually, it's .035", and although I've been told that they come pre-gapped, it's always good to check them.