I've been having
overheating problems with my W58. She'll run fine for 20 minutes then the temp quickly goes over 200. I've cleaned and or replaced all units in the fresh
water cooling system. The
raw water system works fine with plenty of output.
I noticed bubbles coming into the
coolant reservoir and used a test kit to see if the bubbles were
exhaust oriented. They were. This makes be believe that I have
exhaust bubbles coming from a blown
head gasket and blocking the
coolant flow, thus the
overheating.
I used the
engine briefly to get off the
dock when I had to, but now the
engine barely cranks. The
battery is fine. If I try to crank the engine, wait a half hour, try to crank again, let it set and try one more time, the engine turns over enough to fire and run. I tried this intermittent approach to keep the starter from overheating and it worked.
My theory is that the coolant drains back into the cylinder through the
head gasket hole and, since
water won't compress, keeps the engine from fully turning over. Trying to crank intermittently slowly applies pressure in the cylinder and forces the coolant back out of the head gasket hole, thus letting the engine turn over.
If my theory is correct, it confirms the head gasket problem and I'm getting the tools out to replace it. Does my theory "hold water"?