Are my thermostats working right?

[Fl_Richard]

When I cruse around on a plane the temperature runs around 160 degrees. When I drop off and idle the temperature shoots up to around 180-190 then slowly drops.

I assume when on a plane the thermostat springs open up and the engine gets lots of cooling flow and as the intake water is in the 70's the poppets on the thermostat close. When coming off a plane to idle the poppets take a few minutes to open back up and this is where the temperature climbs and the residual heat in the engine takes a few minutes to dissipate.

Is this normal behavior for a 1995 150 or should I look deeper? I have placed the thermostats in a pan of water and measured the temp where they open up. They both open fully between 165 and 175 degrees.

Thanks everyone!

Richard

 

[Mas]

Re: Are my thermostats working right?

I would replace the 175.

MAS

 

[ezeke]

Re: Are my thermostats working right?

I would replace them both; they are supposed to be 143? thermostats that open at 143?.