1983 Johnson 75hp Bogging

Cjw1234

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Aug 1, 2020
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Hi, I have a 1983 Johnson 75hp in-line 3cyl model number J75TLCTE serial number J5829277. It idles good and will run it’s full rpm range and run full throttle all day long. However, it’s tricky getting it to rev all of the way up in gear because to get it going you have to push the throttle very very slowly or it will bog and die. If you jam the throttle and bump the key it will take off like it should. Bumping the key activates a solenoid that puts full directly into the intake of the carbs. (This motor has three separate carbs). The controls for this motor consist of a throttle lever, choke lever, and the key. The choke lever manually closes the choke flaps whereas pushing in on the key activates a simple solenoid that puts raw fuel into the carb intake (I’ve tried to explain that to several people before when they tell me that pushing in the key activated the choke). When in neutral is the only time the choke lever can be used and it will rev the engine all of the way up immediately without hesitation. I’m hoping someone might have some input on this. Thank you!
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
36,269
The control box has a fast idle lever.------A shift / throttle lever .------There is no " choke lever " on this control box !!!----I repeat there is no choke lever on this control box !
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
36,269
Are you prepared to do some simple trouble shooting ?---This may be as simple as opening the low speed mixture needles a 1/8th turn at a time.---Often the bogging goes away when you set this motor up correctly !
 

Cjw1234

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Aug 1, 2020
Messages
8
Yes I am. Unfortunately I’m not at the lake so I can’t do much at the moment but if you could explain what the first steps are that would be fantastic. Possibly pictures or diagrams would be helpful to find the correct adjustment screws and such
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
36,269
Look at the parts break down to find the low speed mixture screws.---Post the compression numbers too.
 

Cjw1234

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Joined
Aug 1, 2020
Messages
8
I do not have a compression tester and the local parts stores aren’t loaning out tools at the moment. And the parts breakdown? I found this image on a parts website
0572464a-cd02-4377-9647-081b739d952f
 
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