yanmar 150hp 800hrs 2010 model

[oldsalts]

Has anyone had this problem ?.
When the engine reaches 3000 rpm an alarm comes on Overboost Alarm. The engine seems to run OK up to that point.
So a mechanic checked it out and claimed it was the Turbo. He installed a new Turbo, Sensor, and switched the Computer from another boat that was working Ok The problem was still there.He checked the pressure relief valve on the Turbo, it was working fine.
So now we're at a stage where we use the boat and don't rev it over 3000 rpm. Does anyone have any suggestions what maybe causing this problem ?.

Mike
from tug " Encore ". (ex Blue Socks )
Sunshine Coast BC

 

[Bruce Moore]

Bumping post delayed in moderation queue.

 

[knotflying]

I am not sure if the configuration is the same as the 180, but did you check the wastegate? There is a rubber hose that can slip off. I would be surprised if that was not seen during repair, It can be hard to see though because it is connected underneath where the filter is. I would also assume that the new turbo came with the wastegate also. And perhaps it is a wiring connection at the sensor plug or downstream.

 

[oldsalts]

Thank you for that info. We'll look into this when we're next at our boat. Mike