Problem diagnosis

[hcb33]

I have a 1987 Evinrude 9.9.

Friday, I ran the motor off and on all morning. Motor ran fine and started fine. I did however notice that the pee stream was a little week, but improved as I gave the motor more gas. Saturday, I ran the motor for about an hour, with quite a few start and stops. The motor did fine and started as usual. After the motor has set for about four hours, I tried to start it. On the first pull, it fired but then suddenly died. Then it would not fire no matter how many times I pulled. Got towed in and took the boat home. Five hours later, I hooked it up to the water hose and the motor started on the third pull, idled and ran in gear just fine.

Any ideas as to what my problems may be? Thanks for the help with this.

 

[DJ]

Re: Problem diagnosis

It's going to be very difficult to tell with it running corrrctly-now.

My GUESS would have been a spark related issue such as coils. When they heat up, they can cause issues.

 

[jbjennings]

Re: Problem diagnosis

It could be a stuck float needle. Has this motor sat for a long time between being used? If so, then clean your carb.
I'd think that the spark was bad also, but since you let it sit for 4 hrs. and then it cranked right up and died, I suspect a stuck float needle.
Just a guess, though. I'd also think it might be a bad kill switch since it should at least run on one cylinder if a powerpack went out.
Just some ideas,
JBJ

 

[hcb33]

Re: Problem diagnosis

I've had some others speculate that it could be a blown head gasket allowing water in. Could that be the case knowing that the motor wouldn't start, yet did later on.

 

[hcb33]

Re: Problem diagnosis

Has this motor sat for a long time between being used?JBJ[/QUOTE

The motor did sit for about three weeks. Is that too long to sit?

 

[Mas]

Re: Problem diagnosis

I would trust it...but I would also keep some tools to remove the spark plugs to inspect for fuel flooding. If it is flooded, as mentioned, it's probably the float stuck where you could just tap the carb bowl to loosen it!?

MAS

 

[JB]

Re: Problem diagnosis

Could be a heat related problem with the ignition, HCB. When you shut it down from running the engine the block, ignition parts, etc. rise in temp for a while.

Get a hair dryer and heat the ignition system while it is at idle. If (when) it quits the parts you heated last are probably having a heat failure.

 

[lyncraft_mechanic]

Re: Problem diagnosis

letting you motor sit for long periods of time can create problems, mostly related to fuel going bad and gumming up your carb.(s) if you are worried about a blown head gasket you should check your compression and pull your spark plugs to check for signs of water intrusion into the cylinders, one way to detect water intrusion would be an abnormally clean spark plug, although I would have to agree with everyone else, it's probably your carb.