1978 johnson 140 overheating problem

[trev]

I have a 1978 Johnson 140hp that is overheating when at trolling speed.I see a very solid stream of water coming out the pee hole while trolling.So I dismissed it being the impeller.I took the thermostats out yesterday and tested them in some hot water and they opened fine.Should I replace the impeller to see if that is the problem.I also have a second problem with this motor.When it is running I have what seems to be a cylinder that drops off and on poriodically.Took a compression test here is how it went #1 95 #2 120 #3 120 #4 120.with the number 1 cylinder being lower than the others should I try to decarb before I go any futher.Thanks for any help in advance.

 

[JB]

Re: 1978 johnson 140 overheating problem

Hi, B2F.<br /><br />Please don't repost a question that has already gotten answers.<br /><br />If you want to add information, just reply to your original post with the new data.<br /><br />That will bring it to the top again.<br /><br />Good luck.