2000 vip thermostat readings.

[crawfisher]

Hello all. Need some opinions on this one. 2000 vip 3.0 mercruiser. replaced impeller, and thermostat ( the correct one and correctly installed) , and checked connections on temp sending unit and on the gauge itself. all appear good. The problem is when running the boat either idling or wot the temp reading goes from 160 to almost 190, then goes back down to 160, then back again and again . This happens continuously, when it is reading 160, count to 4 as it goes to 190, and you can count to 4 and it is back at 160, then it repeats itself. The only thing i have not tried yet is to take off the thermostat housing and see if there is any corrosion restricting the flow of water into the motor, and also wondering if the shutter flap could be hanging up. Has anyone else had a similar problem? thanks

 

[tpenfield]

Re: 2000 vip thermostat readings.

Probably more annoying than harmful . . .

I would think that the thermostat is not opening smoothly and giving the 'over-reaction' that you are seeing in the gauge. Does the 'old' thermostat still work and do you still have it? If so, you could try it for comparison purposes.

 

[crawfisher]

Re: 2000 vip thermostat readings.

Probably more annoying than harmful . . .

I would think that the thermostat is not opening smoothly and giving the 'over-reaction' that you are seeing in the gauge. Does the 'old' thermostat still work and do you still have it? If so, you could try it for comparison purposes.

That might be a possibility but it was doing the same thing with the old thermostat. wonder if it could be an abnormality in the housing of the thermostat. thanks for the reply

 

[Another retired guy]

Re: 2000 vip thermostat readings.

It may just be a bad temperature sensor.