60 hp johnson starting problem

[k_gates45]

I have an early 70's johnson 60 hp outboard and it was running fine previously on old gas and we put new gas in it and all of the sudden it won't start. It turns over fine and has spark but won't start. Every 6 or so turns it backfires and continues to spin without starting. Could this be a timing problem? If so how do you check or fix that? Thanks

 

[JB]

Re: 60 hp johnson starting problem

Howdy, K_Gates.<br /><br />First, post the model number so we can determine the year.<br /><br />Then get a Repair Manual if you don't already have one.<br /><br />Then go to www.outboardrepairs.com and look up wont start. Lots of good advice.<br /><br />Good luck.

 

[ajp]

Re: 60 hp johnson starting problem

Sounds like the starter may be robbing the juice from the system. Or the spark is somewhat weak and only strengtens when the starter lets loose.<br /><br />ist check the simple:<br /><br />Power - battery and all cables.

 

[Joe Reeves]

Re: 60 hp johnson starting problem

K_Gates.... If you've had the flywheel off recently, and didn't torque it properly when re-installing it, the flywheel key would shear which effectively throws the engine out of time, hence the backfire.... if that backfire is actually a backfire going out the exhaust.<br /><br />Flywheel nut torque on that model is 105 foot pounds.<br /><br />However, if the above is not the case, and all you did was purchase new fuel (the same day the engine was running properly), it's possible that you've purchased some water. And since water is heavier than gas or oil, that water would be drawn straight into the fuel supply line at the bottom of the fuel tank.<br /><br />The starter draw scenario as AJP mentions does take place on Battery Capacitance Discharge ignition type engines as the starter grows old. That problem is corrected by simply adding a diode capable of carrying a 12 volt load between the starter terminal cable (at the starter or solenoid) and the terminal that supplys voltage to the pack. Be sure to install that diode so that the current flow is FROM the starter to the pack.

 

[goldenmonkeyboy]

Re: 60 hp johnson starting problem

If the last thing you did before it stopped working was add fuel it's worth checking their isn't a priming problem in the fuel line. Check all fuel connections and lines including the flange on the fuel connector that goes to your fuel tank. Once mine got a small chip in it when I was changing fuel one time and it caused small amounts of air to be drwan into the fuel line giving similar sarting problems.