Thermostat replacement

Status
Not open for further replies.

fishingdad

Member
Joined
Feb 20, 2020
Messages
16
Fluid Motion Model
R-23 (Outboard)
Hull Identification Number
FMLC3042B616
I have a D6 435 C30 with about 500hrs on it and it appears the thermostat is failing. Engine just started running at 170-174 instead of the steady 185 it has been. A mechanic looked at this and says the only way to replace it is to remove the manifold and probably some other parts to get to it. Is that correct or is there a trick to this. Thanks
 
I’m not sure about what your mechanic says but I could have a related situation to your situation. My temperature reading on the VP gauge sometimes shows a rapidly fluctuating temperature reading and other times just shows the steady 185. I am planning to have an expert look at my setup soon and hopefully troubleshoot it. I’ll let you know how it goes and let us all know how your situation goes please. I’m not sure where the water temperature sensor is, I think I have it located on the starboard side of the engine but I’m not sure and I dont have the service manual. There engines have quite a few sensors.
 
I had a similar situation on my Yanmar. Thermostat failure is not very common. Figuring out what may be the issue is also difficult. How easy is it to access the temperature sensor? I would want to check that out before tearing things apart. On mine it turned out that the thermostat was fine, but had dislodged from its proper placement and hence coolant was passing through too freely. It was not a pleasant job getting to the thermostat. Take your time figuring it out. A 10 degree lower temperature is not all that bad. Let us know how i goes.
 
Status
Not open for further replies.
Back
Top