Mace 2.5 overheat error E82

[captstu]

shearwater's generator shuts down after hours of running wits an E82 error - nine overheat.

It has a new Johnson water pump, new impeller, good belt and is pumping lots of water.

Is there a fan got the air cooled engine that I should?????

Ant other ideas?

Thanks. /Stu.

 

[LADYBUG TOO]

There are two separate temperature sensors that could be loose or making a weak connection. One sensor has two blue wires connected to the same contact on the exhaust elbow. You should be able to see them from the top. There is another blue wire connected to a spade connector on the same side as the water pump but aft of it. The spade is in a black plastic ring and is hard to see. Download the Mase parts list to help you locate them. It has a blow up of the gen set with parts labeled. I found it helpful. I am assuming that you have a sound enclosure so be sure that the covers are all in place. Also, while you are at it check the belt tension on your water pump. Make sure it is not too tight (this has nothing to do with overheating, just trying to save you some future grief). You should be able to lightly squeeze the belt. Hope this helps.

Pat
Ladybug, Too

 

[captstu]

Pat, I think you broke the code. Thank you.

During my now $7,000 oil change, the technician who was repairing the first technician's damage noticed the raw water pump on the Mase (I even learned to spell it) was spraying water. Although they overcharged, I was about to leave to meet my kids so I authorized the $550 pump. So far, so good.

We ran the generator and a/c for the hot part of the day and as the sun was dipping, it failed with an E82 (overheat engine) error.

This problem was caused by the new Johnson pump. Apparently, this pump will turn either way - and it is shipped with the cover loose so the installation technician can set the impeller and apply the initial pump grease for the first start. My technician did neither. When I disassembled the pump (easy, three of the four screws were finger tight), every blade was broken. I took it apart, removed the outlet hose and recovered each blade, and backflushed the innercooler to ensure there was not another air leak that was causing the loss of prime and broken blades. Put it all back together and it pumped fine.

4 hours later, another E82 - you gave me the clue. The first E82 was caused by loss of cooling water due to the pump failure due to a prime break due to a loose cap (follow that). After the second E82, I let the unit cool and restarted it - pumped perfectly.

Your note and the parts list provided the clue I needed. Neither of the two mechanics ever looked at the cover, apparently. I only looked critically after I was stumped. Turns out, the Yanmar engine used in the Mase 2.5 is AIR COOLED. The water cools an innercooler that operates like a radiator in reverse - the hot air from the engine passes through the cooler, through the generator, through the electronics box and back to the engine.

The cover from the engine had come partially detached from the front of the engine housing, melted, and sealed most of the innercooler surface. With less surface, the air was restricted somewhat and the engine eventually overheated, triggering the OTHER thermostat (as you mentioned), and the E82.

The first is a water flow indicator, the second it an indicator for block overheat. Should be different error codes, but the manual clearly says the E82 code has two possibilities, corresponding to the two sensors.

Anyway, the cover is home, with me, being stripped to apply new sound material to the inside.

Hopefully this long not will cause folks with a Mase 2.5 to check their cover for detached sound material.

Thanks again, Stu

 

[captstu]

After replacing the impeller in the newly installed pump ($600+ including labor), the Shearwater still had an occasional E82 error.

Thanks to Pat for his advice, above, I found that my generator's problems were both loss of water flow due to an improperly installed pump and a cover that had become separated and partially clogged the innercooler that cools the air for the air cooled engine and generator.

I ordered some Amazon: Thermo-Tec 13575 12" X 24" Adhesive Backed Heat Barrier
and fitted it to the inside of the Mase generator cover. No more hanging cover lining - and no more E82 error.

Thank you, Pat, for the help