Motor has no power when cold

[Greg22]

I have a 1990 Johnson GT150. When the motor is cold the motor has no power. After about 10 or 15 minutes the motor gains full power and the problem will not reoccur until the next outing... I spoke to a wrench and he indicated that the power pack was more than likely the problem. I do not just want to start swapping parts unless I am more sure of the problem. Thanks for any help.

 

[JB]

Re: Motor has no power when cold

Hi, Greg.<br /><br />I think your wrench is probably right, but I agree with you that it shouldn't be replaced until you know it needs replacing.<br /><br />Since this only occurs when the engine is initially started after a layoff, try this.<br /><br />Crank her up on the muffs. Carefully pull each plug wire off, in turn, and see which cylinder(s) are not making power. The dead ones will not cause a drop in rpm when you do this.<br /><br />Can those plug wires make a hot, blue spark to the head? Yes? Not powerpack.<br /><br />More than one plug gets no fire? Let her cool down. Crank her up again and use a hair dryer to heat/dry the powerpack. Picks up all cylinders? Powerpack.<br /><br />Not powerpack? Let us know what you find and we will try another set of tests.<br /><br />Good luck.

 

[Greg22]

Re: Motor has no power when cold

Thanks JB. Let me run this by you or anyone. I went to the lake and started the motor and as I was doing some searching, etc... I noticed that one side of the motor was much hotter than the other (so I shut it down). I am not getting an alarm and I do have H2O coming out the discharge hole. Could one of my thermostats be stuck closed and giving me this problem? Is it possible for the thermostat to open up after a while and the motor to run correctly? I was reading some search items last night and remember reading something about "quickstart" or something such as quickstat. Am I on to something or do I just have two different issues? Thanks.

 

[JB]

Re: Motor has no power when cold

Hi, Greg.<br /><br />What you describe would be consistent with one bank not firing until fully warmed.<br /><br />I suspect you have additional symptoms of your power loss problem.

 

[Greg22]

Re: Motor has no power when cold

OK. Thanks JB. I figured out that one of my thermostats was stuck open. I changed both. I took your advise and when she was cold I took a hair dryer and heated the power pack. I am about 10 minutes from the lake, so I duct taped a couple of those hand warmers to the pack and went to the lake. When I arrived I removed the hand warmers and cranked her up. The motor ran great. I am going to replace the pack. <br /> New question. The water from the tell-tale is cool. Should it be? I can touch either side of the heads for about 7 seconds before it becomes unconvertible. Thanks.

 

[roscoe]

Re: Motor has no power when cold

Sounds normal. You should be able to hold your hand on the powerhead without discomfort for 3 to 7 seconds, depending on the motor, and your hand. What is the temp of the thermostat? Outboard thermostats are much lower than in an auto. Mine is only 130 degrees. I can hold my hand on the powerhead about 5 seconds.