1994 225 Johnson Overheating

[Captn Dave]

I just repowered my boat with a 1994 225 Johnson.
At Idle the temp is around 160. Cruising at 4000-4500 RPM the temp climbs to 175.
The PO said he recently changed the thermostats and water pump.

I pulled the thermostats and they do appear relatively new. I checked them on the stove and they started to open around 130.
I pulled the poppit valve and it appeared to have not been removed in awhile. There were some deposits on the valve and housing. I cleaned the valve and the housing and reinstalled it.
The tell tale is strong.

The gauge and sending unit are from the original engine.

Touching the heads at Idle I was able to do the 3 second test. I believe the port head was hotter.

Anybody have any ideas?

 

[jwbmarine]

Re: 1994 225 Johnson Overheating

u do not have an overheat problem at all,...absolutely normal....

 

[JoLin]

Re: 1994 225 Johnson Overheating

I have had the same "problem" since I bought my boat w/1995 175 hp Johnson last Fall. EXACTLY the same temp readings you're seeing.

I basically drove myself nuts and did everything you have (like, 2 or 3 times ) until I bought a $40.00 Harbor Freight non-contact IR thermometer and found out that the motor is running right on spec. My gauge or sending unit is screwy.

 

[Reel Quick]

Re: 1994 225 Johnson Overheating

Gotta love HF!Got one down the street.Go in for one thing come out with 6.I have the same temps on a 97 225 O Runner.Oh,I forgot to mention I DE-Carbed with Ocean foam and lost some of the heat.My 2 cent`s.