Postby BarryK » August 19th, 2020, 12:49 pm
Yes, the big heat exchangers are under small hatches under the couches. There are also hatches on the floor over the V-drives. I am looking for advice about how to remove the exchangers and disconnect all of the hoses. It is a very tight space to work in. I would at least like to free them up so I can remove the end caps to look for debri.
The U coolers are on the front of the engine. There is plenty of room to work there. I had a recommendation to inspect the inside of the U coolers to look for obstructions.
The reason for all of this investigation is that the port engine puts our excessive exhaust steam over 3000 rpm but the engine temp stays steady at 165 deg. It looks like a steam locomotive. The steaming stops when I throttle back to 3000. The coolant level has been rock steady for a while so I do not think it is an antifreeze (coolant) leak. The engine runs smoothly and it does not use any oil.
The starboard engine temp runs slightly hotter at higher rpm, 170-175 deg. but there is normal minimal steam from the exhaust. Temp returns to low 160s at idle.
I have circulated Rydlyme through both engines using a closed loop with a sump pump to circulate the solution. This did not help with the above issues.
I suspect that the risers and elbows may be getting clogged on the steaming engine. The elbows on that engine are about 10 deg warmer than the other after a 3000 rpm run. I checked elbow temps with an IR thermometer gun when back to idle for a few minutes. 108 port, 98 starboard. The difference may be greater when actually running at speed. Former owner claims that the elbows and risers were replaced about 2 years ago but he did not produce receipts for the work. They look pretty new and paint is clean and intact.
The raw water pumps were recently professionally rebuilt including new bearings and impellers. Belts are new and tight.
The only thing I have not yet done on the steaming engine is to replace the hose from the V drive to the raw water pump intake. It looks OK but hard to inspect under the engine. I replaced the starboard side since it was collapsed (metal spring was corroded) and it was restricting intake flow.
I have not changed the spark plugs yet. I dread trying to get to the outboard sides of the engines, very tight spots. I'm looking for advice here as well.
Thanks!
Barry