1976 70 hp hesitates after warmed-up

[Greycup180]

After running around the lake well, we will go in to hook up a tube or skier (either shut down or idle) and then when we full throttle, the motor wiil hesitate and when I pull back and go forward it will stall. Starts right up, but after full throttle will hesitate and stall. If I work the throttle back and forth I can eventually get it going but I have to unhooke the tube or ski rope then come back in and quickly hook up again to keep it going. Only seems to hesitate and stall after a short rest from a WOT ride. Tune up last year but I cannot remember the last time the carbs were thoroughly cleaned.

 

[xtraham]

Re: 1976 70 hp hesitates after warmed-up

when it hesitates try bumping the choke does speed up or die out?

 

[Greycup180]

Re: 1976 70 hp hesitates after warmed-up

when it hesitates try bumping the choke does speed up or die out?

 

[Greycup180]

Re: 1976 70 hp hesitates after warmed-up

when it hesitates try bumping the choke does speed up or die out?

Thanks. Going back to the lake on the weekend and will try your suggestion. By bumping the choke, do you mean holding the choke switch up while the motor hesitates?

 

[xtraham]

Re: 1976 70 hp hesitates after warmed-up

you should have to hold in on the key switch are another switch assuming you have the choke lever set for electric, when the engine boggs just momentarly bump the choke activation button let us know if the engine dies or picks up rpm's good luck

 

[jksnyder]

Re: 1976 70 hp hesitates after warmed-up

I had a similar problem with my '71 60 HP.....see my post.
Just found the problem to be the points....not set properly and one set failed intermittantly after the engine heats up. Took a long time to trace, but now I'm a happy boater.d

 

[Greycup180]

Re: 1976 70 hp hesitates after warmed-up

you should have to hold in on the key switch are another switch assuming you have the choke lever set for electric, when the engine boggs just momentarly bump the choke activation button let us know if the engine dies or picks up rpm's good luck

Just got back from the lake - I held the choke switch up when the engine hesitated and was just about to die, and with the choke on, the engine died out - did not rev up. Hope this is good news!

 

[xtraham]

Re: 1976 70 hp hesitates after warmed-up

check compression, plugs, look for cracked coils, make sure timmer base is advancing with the throttle, you can start it on muffs and pull 1 plug wire at a time listen for change in engine speed if one does not change thats the cyl. with the problem, let us know the outcome of these test...