I think you've got bigger problems than just rust on the spark plugs. I'm not sure what's holding that mess together. If you heat that up or smack it with a hammer real hard, it may just come apart on you. You can either A) run it till it breaks, or B) pull the engine and go through it. Changing the plugs at this point is like putting a band-aid on a bullet hole.

Thanks for all the posts guys.

Its not my boat but a friends. Im helping him out. He had a water pump/thermostat issue. So he wanted to clean up, change plugs, wires, new exhaust.

May be a lil late i know.

So just gunnah try to get them out, get it back together and see what happens.

Thanks for all the responses.

Probably try the diesel and coke before getting into purchasing the Naval Jelly or muratic acid.

Thanks SHU

Wow, thats pretty bad. What did the Exhaust manifolds look like!?!?! Let me know if you can't fix them, I have a really nice set of low hour heads that will fit.

Nick

too hard to tell what was actually leaking-heads or exhausts. But it dont look too good either way.

Its a 502 Mag MPI motor.

We'll know more this weekend after trying out ALL the option listed.

Should be interesting.

Looks like some exhaust studs / bolts are broken too ...just pull the heads and see if a machine shop can salvage them ...

Yeah exhaust bolts on this side ALL had to be cut off. There was either too much rust to slip a socket on or the bolt head was soo curroded it was not a hexagon shape anymore. We die grinded w a cutoff wheel all the bolt heads. Now we have 3 cut bolts to deal with.

Also it does look like a couple head bolts have been compromised-fully disintegrated by rust.

Wait n see what he wants to do. Not good anyway you look at it.

Simple fix now and HUGE problems later.

Or fix it all now.