My new to me md7a has overheating problems.
This engine is an aftermarket-converted freshwater engine. The raw-water circuit has issues from barnacles on thr intake. that i can fix, and sludge in the exhaust pipe i ready cleared. But when I still noticed overheating even with a stream of water out the back, I checked ant ther is little coolant in the regime, and it is not pulling coolant from the reservoir. Yup, that means a leak, and I found the problem. It seems the is a 5/8 inch hose connecting from a 1/2 in stub st the heat exchanger to a 3/4 stub at the engine. It leaks at both ends. One solution would be to add an adapter and put in the proper sized hoses, and the replace coolant and burp the engine, but is there any reason I should not just bypass the heat exchanger and just convert yo the original raw water system. It seems it eould be much simpler.
I understand that fresh water systems are supposed to run hotter and cleaner, but this engine is already 40 yrs old.
Of course I do not know when the fresh water conversion was done, but i do not see any svmcale in the thermostat housing.
Any comments? The buildup of sludge in the exhaust does bother me, too.
This engine is an aftermarket-converted freshwater engine. The raw-water circuit has issues from barnacles on thr intake. that i can fix, and sludge in the exhaust pipe i ready cleared. But when I still noticed overheating even with a stream of water out the back, I checked ant ther is little coolant in the regime, and it is not pulling coolant from the reservoir. Yup, that means a leak, and I found the problem. It seems the is a 5/8 inch hose connecting from a 1/2 in stub st the heat exchanger to a 3/4 stub at the engine. It leaks at both ends. One solution would be to add an adapter and put in the proper sized hoses, and the replace coolant and burp the engine, but is there any reason I should not just bypass the heat exchanger and just convert yo the original raw water system. It seems it eould be much simpler.
I understand that fresh water systems are supposed to run hotter and cleaner, but this engine is already 40 yrs old.
Of course I do not know when the fresh water conversion was done, but i do not see any svmcale in the thermostat housing.
Any comments? The buildup of sludge in the exhaust does bother me, too.