55 HP Johnson - occasional no spark - HELP!

[torry]

Could someone help me... I'm frustrated!<br /><br />Our motor will start in the driveway... but not in the water. <br /><br />When I test the motor before going to the lake, the ignition fires and the motor will start. After bouncing down the road to the lake... the motor won't start in the water. However 20 minutes or so later, still in the lake, it usually will start! Strange eh!?<br /><br />Checked all electrical connections to ensure they were tight. <br /><br />How do I troubleshoot this problem?<br /><br />Thanks, <br /><br />Frustrated Mike

 

[torry]

Re: 55 HP Johnson - occasional no spark - HELP!

One more thing...<br /><br />It's a 1976 55 HP Johnson...<br /><br />Sorry about the ommission.<br /><br />Mike

 

[The Marine Doctor]

Re: 55 HP Johnson - occasional no spark - HELP!

Does it stall on the water and not restart?<br /><br />The bouncing down the road is jarring something loose. Broken wire maybe in the harness? Poor connection of an electronic part within your powerpack.<br /><br />TMD

 

[torry]

Re: 55 HP Johnson - occasional no spark - HELP!

Once it's in the water and has started, it starts first time everytime (in the water). It has never let us down once it has started... in the water.<br /><br />I checked the connections as best I can. All seems well. <br /><br />Mike

 

[kd6nem]

Re: 55 HP Johnson - occasional no spark - HELP!

Any chance that it is flooding out- carbs overflowing since the motor is tilted up and bouncing? Maybe the float's needle valve is worn or something?

 

[torry]

Re: 55 HP Johnson - occasional no spark - HELP!

thanks for the idea, but no, I don't tilt the engine during transport and it is definitly getting fuel.

 

[kd6nem]

Re: 55 HP Johnson - occasional no spark - HELP!

My thought was if it were spilling TOO MUCH fuel into the motor during the trip, whether tilted or not. But really, you should start by checking to see whether you have a good strong spark. Might not be too convenient to check that in the water, but if it doesn't do it at home, only after a trip, that's the place to check. Electrical won't consistently get better after twenty minutes or whatever, but flooding probably would. The other thought might be to check the spark when getting home after a trip to the lake. I've seen a similar issue with my '68 Johnson 55, and it was excess fuel getting into the motor while travelling, causing it to flood. Checking the spark will right off tell you whether the problem is electrical or fuel related.