69 johnson 55hp dies at low rpm when warm

[dukerdog]

i have a55hp johnson 1969 hydro shift. starts great, no hesitation on accelleration,everything seems good until i get back to dock. when in no wake zone it dies at low speed. it started as a miss, 2 trips later it would stall but restart, next trip stall and no restart. i have replaced all wires- soldered connections, rebuilt carbs, checked points new plugs, good compression. any help please?

 

[CATransplant]

Re: 69 johnson 55hp dies at low rpm when warm

When did you last change the water pump impeller? It could be overheating, due to low water flow at low engine speeds. When it's running at higher RPM, enough water is circulating to keep it cool enough to run OK. Then, when you slow down in the no-wake zone, the water flow diminishes, and the residual heat in the engine cases it to overheat and stall.

That's my prediction.

 

[Thunderhawk]

Re: 69 johnson 55hp dies at low rpm when warm

Possible lean sneeze, low speed needle issue, I believe low speed needles are 5/8 turn out from seated. you may start there, good luck

 

[dukerdog]

Re: 69 johnson 55hp dies at low rpm when warm

i have relpaced water pump before season. should i install telltale pisser on this motor also, i have seen instruction on how to do this.