Carver Owners Forum

New to me 1984 3607 AC. Did my annual maintenance and replaced the spark plugs. Based upon recommendations I put in Champion RV12YC plugs
What I pulled out were Champion RV8C plugs - put in by PO

The RV8Cs were pretty black (of course, I have no idea how long there installed.

So, what are your recommendations?

I think I ran the RV12YC in mine most of the time. The last few years I used the ACDelco R43TS or R44TS (can't remember which).

I have used MR43T's for years. Always happy with those. The manual for my 350XL's specs out MR43T, MR44T, or RV8C. The gap is disclosed as .045. Most stock plugs come gapped at .035, so need some adjustment there. er

JeffandErin wrote:Source of the post The RV8Cs were pretty black (of course, I have no idea how long there installed.

I wouldn't base any decisions as to heat range based on those plugs being black if that is what you are inferring. You really can't take a definitive plug reading on an older carbed engine that has been just idling around.

Cooler wrote:Source of the post Most stock plugs come gapped at .035, so need some adjustment there

Cooler your engines are much newer with a different ignition system I think, unless the ops have been upgraded.

These kind of spark plugs are fairly cheap, so very good to change regularly. Good job keeping up with the maintenance.