Capt. DAD Any luck re over heating problem? We're all interested to learn results. Hope it is moving forward well in your research of the cause - Best, W.
Problem solved! We removed for third time the coolant heat exchangers and found them clogged again, so we installed new sea water strainers before the pumps as it should be. Exchangers were cleaned and washed with acid to eliminate any possible deposit. Now I highly recommend to the users of these Volvo engines to install sea water strainers before the pumps to eliminate the problem caused by the pump working as a macerator and sending all the garbage to the thin tubes of the heat exchangers. With new impellers and strainers the boat is running fine at 3200 RPM and 185 F. Cross my fingers!
Strainers??? So, If I understand what your saying, there were no strainers before the sea water pumps? Is this a normal installation practice for this setup? ,Ralph
From what I understand, Volvo set them up in the beginning with the seawater strainer after the raw water pump. Then in later years switched it around and put the sea strainers before the seawater pump. I do believe the water inlets in the drives have screens on them.
Capt. Dad, Thanks for the follow up and I'm glad that you got your problem sorted. Are you still using the sea strainers on the motors themselves (which btw way are not in a great location directly above the alternator)? Are you by chance able to post a photo of your new setup? Be well, max
Hi Capt. DAD Glad you located and seem to have solved your twin engines’ similar overheating problem. You mentioned early-on: “Boat performed ok the first 200 hours.” i.e. prior to overheating suddenly appearing. After a period of time and collective forum thinking, currently you mention; “We removed for third time the coolant heat exchangers and found them clogged again”. 1. Did you experience the overheating problem being relieved each of the first two times you cleaned the heat exchangers; then it soon returned, as compared to your first “... 200 hours.” of operation... or was the third time of cleaning them the only one that actually stopped the overheating? 2. Are you cruising in different waters as compared to your “... first 200 hours.”; i.e. waters that hold more seaweed or other organic flotsam than the waters in which you cruised during your first 200 hours of operation? Reason I ask these questions is to determine the following: If you are cruising in same general vicinity as the first 200 hours of operation, and suddenly getting your heat exchangers plugged as compared to the first 200 hours then the water’s increase of seaweed or other organic flotsam is notable. I feel this is important to ascertain, as it may help to understand to what extent the ocean areas that you ply are altering their general composition... due to climate circumstances. Happy Boating! Thanks, W.
Hi, This was in the very first post in this thread, nowhere else do I see any mention of a second cleaning of the coolers nor any improvement between cleaning and fouling occurring. Cpt. Dad - What was the difference in the cleaning procedure that fixed the problem when done the third time compared to the other two times?
The scene is 250 hours of use over three years, I would guess the temperature has been both up and down during this period and that certain things thrive at certain temperatures, clogging the cooling system...