rvukovich

[rvukovich]

I have a 99 - 35 horse Johnson motor that shuts down on me. I can go a week and it won't shut down then it will happen maybe 4 times in a day. The overflow is good and the discharge has a steady flow of water so I know the water pump is working. I think it might be the S.L.O.W. warning system. Can the heat sensor that shuts the engine down be replaced?

 

[rodbolt]

Re: rvukovich

hello<br /> there is no shut down sensor. if it has SLOW it will cause a misfire not a shutdown. if it has slow you will have a tan lead going from the head tothe pack. could be a emergency stop switch.. need more info on the motor. a model # would be nice. the causes of shut down can be overheat until he pistons stick to the cyls. could be fuel tank not vented, can be ignition, thats why a systematic trouble shooting is nessasary to comfim the operation of each subsystem. I always start with a compression and spark test. then sometimes you have to have the engine running with the test equipment attached to find the problem.

 

[rvukovich]

Re: rvukovich

Thanks for your help. The model #J35TEL3EEM. Engine family # X1PXMOO34210. We did a compression test in the fall the top cylinder was 148#, middle 148#, bottom #150. The motor is 34.5 cubic inch, ignition features - slow and quick start. I really appreciate any ideas you might have, because I brought it in for service and the guys don't have a clue as to the problem.

 

[OBJ]

Re: rvukovich

RV...when it shuts down, does it just shut off or does it cough and choke a little before doing so.<br /><br />If it just shuts down, that may lead to an ignition or wiring problem such as a wire broke and opening in a certain position or going to ground.<br /><br />If it chokes and coughs before shutting down, may lead to a fuel starvation issue.<br /><br />How hard is it to restart and what do you have to do?

 

[rvukovich]

Re: rvukovich

the motor just shuts down and it restarts right away.

 

[DHPMARINE]

Re: rvukovich

And you just turn the key or pull the rope and it starts right up ? ? Or do you do something else first ?<br /><br />DHP

 

[rvukovich]

Re: rvukovich

The motor stops when I am going full power. So I wait until the boat comes to a complete stop then just turn the key. The motor is electric start.

 

[OBJ]

Re: rvukovich

RV...when it stops, are you in a turn, going straight or anything else? Something is causing the ignition to go dead. Have you check the wiring harness for pinched or bare wires? Take a look around the block and along the harness to the key switch.

 

[rodbolt]

Re: rvukovich

hello<br /> a quick test is to isolate the black/yellow wire at the pack. some packs have a seperate lead and others you have to push a pin from the connector. both are easy. after isolating the key swicth and emergency stop circuits this way, if it dies, then you can attach a CD-77 meter to it and watch the meter. if it dies at high speed like you turned off the key odds are the pack is failing.