ASPEN (Columbia C29 #131) just splashed yesterday. The early model A4 was acid flushed on the hard, rebuilt raw water seacock, new hoses to the new Moyer pump, new thermostat, and once in the water checked for leaks and water from the exhaust. All ok. I motored from the yard to the slip. 3/4 way there the engine overheated big time. At slip a stepwise investigation ensued. I removed the tstat housing and found the stat fully open as one would expect, but absolutely no water inside. I then checked from the intake inward. Water comes in through intake, makes it to the T-fitting for flushes, makes it to the pump, exits pump when hand cranked, makes it to the T-fitting at the side plate, makes it to the tstat housing, and eventually makes it to the exhaust. Perplexed, I started the engine and everything was perfect for 30' when I shut her down and wondered what the problem was. I haven't a clue. I left the tstat out, but I doubt that was the problem anyway.
Is it possible that the acid flush caused something to flake off and obstruct the inflow? That doesn't make sense either as the t-fitting at the side plate would allow water to the crossover (late model head) and there was none there. Plastic bag idea over the intake strainer seems more plausible. Is it advisable to repeat the acid flush? There sure was alot of muck when I initially flushed it (1 gal muriatic to 5 gal water, let stand 15', then flushed afterward with 15 gal water.) A higher concentration?
What about heat damage to the engine? Noticed some oil (not alot) on top of the bilge water, nothing in the engine compartment. Ran great afterward without obvious abnormality.
Long post, I know, but am more than a little worried.
Doug
Is it possible that the acid flush caused something to flake off and obstruct the inflow? That doesn't make sense either as the t-fitting at the side plate would allow water to the crossover (late model head) and there was none there. Plastic bag idea over the intake strainer seems more plausible. Is it advisable to repeat the acid flush? There sure was alot of muck when I initially flushed it (1 gal muriatic to 5 gal water, let stand 15', then flushed afterward with 15 gal water.) A higher concentration?
What about heat damage to the engine? Noticed some oil (not alot) on top of the bilge water, nothing in the engine compartment. Ran great afterward without obvious abnormality.
Long post, I know, but am more than a little worried.
Doug
Comment