It is a very easy off and on job. It only takes about an hour to complete per motor and thats with me and a six pack. 12 bolts three plugs and two vacume lines and the plenum is off. Way easy, then its 4 bolts and the rails off. Trust me anyone can do this. Then just pull the filters out the end of the injectors and spray out with b 12.

Brown mushy or flaky substance, depending on how wet it is, is exactly that....varnish.

varnish is what it was and random debree just like the stuff that plugs up the screen in the vst unit same type of filters in the injector ends.

johnlaskowski, Best post on this site!!!! (for me at least) I was having similar problems with my 496, eevn took it to my mechanic, and he checked all parts of the ignition, and proceeded to determine that it was springs or valves... Read this post, then called him and he said didn't seem likely, spent 6 bux on fuel injector cleaner and 45 minutes, and just like that it's all good, even poosted up here and was thinking valve job @ 16 hours!!!

http://www.offshoreonly.com/forums/g...exhaust-2.html

Thanks for sharing!!!!!!

THANK YOU

Its sad when a car mechanic fixes boats better than the supposed experts at the dealer. I guess from now on ill just do all my own repairs as I have more knowledge on these mpi systems then any dealer by me.

But heck its fixed and the boat runs goo so happy boating.