Mercruiser Woes-What Next?

[pelican]

if you're smart,you're gonna replace the engine with a complete new engine-too many horror stories !
it's gonna cost more,but,in my opinion(i own a marine repair shop) it's the best option-it's also the only way i repair problems like this.
using a "long block" that's reman'd is a crap shoot at best.

manifolds and risers-5yrs max-flushing has no bearing here.overheating isn't a factor either-the water passages will erode away,allowing the water to enter the cylinders via the exhaust valves-eroding the valves and causing a low,or,no cmpression situaton.remember,we're talking about sea water-this is where the cooling water is expelled.sea water in an engine isn't a good thing-think about the dissimilar metals here...
if you're engine "locked up" due to hydro locking-you would've had a few tell tale signs to alert you to a potential poblem-"steam" from the crankcase vents- breather tube,where it goes to the flame arrester,salt residue may be present as well.you may have noticed a drop in max rpm too...
getting into the habit of a yearly compression test is usefull-it gives you the opportunty to inspect the plugs-look for plugs with either a rust stain,or,plugs that are snow white-steam cleaned-this is another tell tale-this shows there's water entering the cylinders...

trust me,the advice i gave is the best...