Question on Head Temp - 1983 Johnson 90 V4

[bigriver79]

The starboard side is noticeably warmer to the touch.
Compression is 130, 130
Port side is 120, 120


Is this something to be concerned about? I don't think its getting too hot but I have no idea what too hot is as far as temp #'s.
Freshwater engine, runs good, new water pump. I'd rather not go unbolting stuff and break off bolts.

Alarm has never come on although I never assumed it worked anyway.


Any suggestions, comments appreciated.

 

[jakedaawg]

Use temo sticks or infared gun. Post some measurements.

On another note, manually ground the tan wires coming from each head. If alarm sounds you know your horn works. It does not tell you if the sensor works though.

Test sensor by removing and placing in hot water. Use ohm meter and determune at which temp the sensor closes. Or just replace them.

 

[jakedaawg]

You may also want to pop off the exhaust covers on the port side and have a looks see. You are technically within spec but I personally like to see closer comp specs.

 

[bigriver79]

You may also want to pop off the exhaust covers on the port side and have a looks see. You are technically within spec but I personally like to see closer comp specs.

Thanks, I will try to get some #'s. Those were cold compression readings BTW.

 

[bigriver79]

138 degrees on starboard side.
123 port.

That's at idle after running for about 20 minutes. I gave it some gas at one point and head temps dropped immediately so I'm guessing thermos are working.

Do these temps sound ok? Ambient temp is 85.

 

[emdsapmgr]

Not necessarily. Once you give the engine some fuel, the rpm's go up. When the pump volume also goes up, the pressure relief valves will open, flooding the heads with tons of extra cooling water. Once those valves open, the cyl head temps will go down maybe 20 degrees. That's normal. The stats could still be sluggish, and that affects cooling at idle only.