Yanmar 315 6LPA STE Overheating Just above idle

[rcbulloch]

New to me 2000 Albin 28TE engine box owner with 2015 Yanmar 315 6LP. This listserv is fantastic to learn about my Albin since I don't see many here in the PNW (Friday Harbor--San Juan Islands). Thank you for your contributions and enthusiasm for the boats as it weighed heavily in my decision to buy mine when they don't seem too common up here.

I am having an overheating problem and my local diesel mechanics--when I can reach them--all have different theories.

Boat begins to heat up if I try to push it past 6.5-7 knts. If I throttle down, the boat immediately cools back to its "normal" operating temp. We have replaced the impeller twice (new) and it has not made a difference. One mechanic suggested it was a collapsed exhaust hose after going through most of the raw water cooling system and not locating a problem. (We did not find any collapsed hoses). Another suggested it might be a fuel filter or fuel starving issue. Yet another says it is the raw water pump failing at higher pull. All say it seems relatively minor, but none can give a date to get the work done. I'm learning I may need to do some of this myself if Im going to have a boat like this on these islands.

I am finding some coolant in the bilge and small amounts near the diesel heater to the cabin.

I would love to enjoy the last days of our indian summer up here on the boat. Any suggestions or ideas are appreciated.

Thanks, Bob

[catalina_mike]

It's waterflow related. Either low coolant or raw water side. Raw water side is impeller on raw water pump, heat exchanger restriction from clogging. How does the water flow look in the exhaust. If water flow looks good focus on the heat exchanger and coolant level.

[Ben423]

This sounds like a coolant flow issue. If the raw water pump is working properly the next step is to check the heat exchanger, oil cooler and transmission cooler. If you don't know when they were last boiled out, it's a good idea to do that now. Clean heat exchangers and a fresh impeller will likely fix the problem.

[GeorgeS]

My boat is same as yours, Albin 28 TE yr.2000 with Yanmar 315 named "2nd Wind" overheating at 3000 RPM . We just spent a lot of our play money to have this problem rectified by Niemiec Marine in New Bedford. ( PS : They are superb mechanics) They sripped out the intercooler , and various other coolant related parts including the cooler on the transmission , now runs perfectly at all RPM's. Also you may want to check the exhaust system for leakage at the same time.

Good Luck, George S.

[GeorgeS]

New to me 2000 Albin 28TE engine box owner with 2015 Yanmar 315 6LP. This listserv is fantastic to learn about my Albin since I don't see many here in the PNW (Friday Harbor--San Juan Islands). Thank you for your contributions and enthusiasm for the boats as it weighed heavily in my decision to buy mine when they don't seem too common up here.

I am having an overheating problem and my local diesel mechanics--when I can reach them--all have different theories.

Boat begins to heat up if I try to push it past 6.5-7 knts. If I throttle down, the boat immediately cools back to its "normal" operating temp. We have replaced the impeller twice (new) and it has not made a difference. One mechanic suggested it was a collapsed exhaust hose after going through most of the raw water cooling system and not locating a problem. (We did not find any collapsed hoses). Another suggested it might be a fuel filter or fuel starving issue. Yet another says it is the raw water pump failing at higher pull. All say it seems relatively minor, but none can give a date to get the work done. I'm learning I may need to do some of this myself if Im going to have a boat like this on these islands.

I am finding some coolant in the bilge and small amounts near the diesel heater to the cabin.

I would love to enjoy the last days of our indian summer up here on the boat. Any suggestions or ideas are appreciated.

Thanks, Bob

My boat is same as yours, Albin 28 TE yr.2000 with Yanmar 315 named "2nd Wind" overheating at 3000 RPM . We just spent a lot of our play money to have this problem rectified by Niemiec Marine in New Bedford. ( PS : They are superb mechanics) They sripped out the intercooler , and various other coolant related parts including the cooler on the transmission , now runs perfectly at all RPM's. Also you may want to check the exhaust system for leakage at the same time.

Good Luck, George S.

[jcollins]

Moving topic to maintenance forum.

[adamthier]

I have a Cat 3126 in my 35CB. also moderate overheating. running warm. Just had the heat exchanger and intercoolers completely torn down and cleaned out. It's not a cheap job. But you need to do it every 4-5 years. zincs, impeller bits, etc. will form a clog. Even a small reduction in flow has a material impact.