1983 Johnson GT150 idles fine on muffs but bogs to die in water

moon5115

Recruit
Joined
Oct 27, 2021
Messages
2
I have this engine on a 97 Raycraft bass boat. Engine was running rough so i did tune up and then maintenance. Changed spark plugs and checked all wiring and connections. Rebuilt carbs, checked and cleaned fuel pumps and changed fuel lines. cables may have been turned off of where they were. I have not checked compression, do not have a compression gauge. Motor did run strong throttled up and on plane before i rebuilt carbs. So i figure I did something wrong. idles fine on muffs and in the water. Throttles up fine on muffs but under a load in gear in the water is when it boggs down and tries to die.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,860
Some will argue.-----A compression test is always step #1 on these crossflow engines.----Post the values you get.-----On muffs----" in gear " ---Is still neutral and that test means nothing !
 

moon5115

Recruit
Joined
Oct 27, 2021
Messages
2
Some will argue.-----A compression test is always step #1 on these crossflow engines.----Post the values you get.-----On muffs----" in gear " ---Is still neutral and that test means nothing !
Thanks for answering back. I appreciate it. I will get a compression gauge as soon as I can and get the boat to the house to check it (weather permitting). I will post the values as soon as I can. I would take it to a shop but the reputable ones around here won't work on anything this old and the ones who will pad the bill. So I appreciate your experience. Have a good night.
 
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