No Acceleration on 1983 70 HP 3-cyl

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Runaboat

Cadet
Joined
Jun 27, 2009
Messages
14
Help!! Can not get this thing to run right for the life of me. Hadn't been run in years when I bought it so rebuilt the carbs, repalced the plugs and power pack. Has strong spark, good compression, and is getting fuel. It will start right up and idle fine, put in gear and it runs pretty smooth at 5-8 mph. But give it any more gas than that and it stalls dead. Any ideas greatly appreciated!
 
kenmyfam

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,385
Re: No Acceleration on 1983 70 HP 3-cyl

Link n Sync before you go anywhere else as it is a free thing to do other than some time.
 
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Runaboat

Cadet
Joined
Jun 27, 2009
Messages
14
Re: No Acceleration on 1983 70 HP 3-cyl

Yep, have done ... twice ... according to the manual. Of course, these were the first two times I've ever even tried working on a mototr! But everything seems fine, all 3 throttle valves fully close and begin opening at same time as cam roller aligns with mark on cam, pick-up timing at TDC, WOT timing done per Joe Reeves method.
 
kenmyfam

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,385
Re: No Acceleration on 1983 70 HP 3-cyl

Runaboat said:
Help!! Can not get this thing to run right for the life of me. Hadn't been run in years when I bought it so rebuilt the carbs, repalced the plugs and power pack. Has strong spark, good compression, and is getting fuel. It will start right up and idle fine, put in gear and it runs pretty smooth at 5-8 mph. But give it any more gas than that and it stalls dead. Any ideas greatly appreciated!
Click to expand...

How much fuel is it actually getting.
Remove hose from pump to carbs and run it into a container. Crank the motor and see what comes from pump.
Strong consistent spurts (at least 7 or 8 in a row) = good pump
Strong initial spurt and then progressively weaker = failing pump
Next to nothing coming out = bad pump.
You also need to make certain that there is no air getting into the fuel lines on the way to the pump.
 
R

Runaboat

Cadet
Joined
Jun 27, 2009
Messages
14
Re: No Acceleration on 1983 70 HP 3-cyl

Good point! Will do that and see exactly how much it's getting.
 
S

skippy2235

Petty Officer 2nd Class
Joined
Aug 24, 2009
Messages
138
Re: No Acceleration on 1983 70 HP 3-cyl

your low speed mixture is lean.
turn your needle abit, I went 3 turns.
 
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