1982 70 hp Johnson, looses power after hot soak

Bradg

Seaman
Joined
Jun 25, 2004
Messages
52
My 70 hp johnson looses power and stalls on acceleration from
a stop. This problem only happens after tubing for a while then
coming in for a rest of 15 mins or more. The engine will loose
power /stall on medium to hard throttle. The only way to get going is to feather throttle( 15-20 seconds) then it takes off and
is fine until next rest stop. I had the carbs redone,
thermostat replaced, and water pump impeller replaced. The problem was there last year but would only happen 1 time in a full day of boating. compression fine 130,130, 125.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: 1982 70 hp Johnson, looses power after hot soak

I'm guessing that the link/synch of the carb linkage is slightly out of adjustment and or the idle orifice/s may be restricted.

What plugs are you running and what are they gapped at? Should be Champion L77JC4 or QL77JC4 gapped at .030".Are the plug wires in good condition and secure on both ends?What elevation are you running at?
 

Bradg

Seaman
Joined
Jun 25, 2004
Messages
52
Re: 1982 70 hp Johnson, looses power after hot soak

Have champion QL77JC4 gapped at .030. Plug wires are in good
condition and secure. elevation in saskatoon 1654 ft.

The carb overhaul was done at dealer, so you would think
link/synch would be ok.
 
Top