2H Johnson motor won't fire

[RRobinRoberts]

Here is the issue, I have a 1985 2hp Johnson outboard. I had torn it completely apart to replace the powerhead gasket which was leaking fumes. I did not change or remove anything to the crankshaft, piston or magneto.

I cleaned and replace the gaskets and other items that come with the carb. kit. I checked the reed valves, float, high and low speed adjustment screws and that all the orifices blown with compressed air. Removed and inspected various times.

I have good spark. I have tried everything I can think of to get it to fire. Even when as far as spraying starting fluid (big no, no) into the spark plug chamber. Nothing works. Does not even try to fire. It acts like the kill switch is grounding the spark, but I have good spark, tested multiple times in various ways.

The compression is 70PSI.

Fuel line and fuel shut off valve are new, gas tank clean out with new screen. But even if the fuel isn't reaching the spark plug it should fire with a squirt of fuel or starting fluid in the spark plug chamber, even if just for a moment.


I thought maybe the timing is off because of tearing it down to change the powerhead gasket, is that possible? The key looks to be in place.

This engine is as about as simple as it could be, yet I have run out of ideas on what it could be.


It ran before I replaced the powerhead gasket, but only at fast speed. I found out when ordering parts and looking at the carburetor diagram that the previous owner had reversed the low and high speed adjustment screws. It is, also, obvious when you look at the length of the screws and compare with location to the carburetor.


The good news is that I have disassembled and reassembled this motor so many times, I know what tools I need and can do it comfortably


All ideas welcome.

 

[vics]

You say the spark is good, but how good ? will it jump a 1/4" ?

If the spark is good it ought to at least fire briefly if starting fluid or fuel mix is sprayed into the intake

Have you tried a new plug ?

 

[RRobinRoberts]

New spark plug, Tested with a spark plug tester, can see the spark. I, also, grounded the plug to the motor, can see the spark across electrodes in the light of day. How do I check for a 1/4"? Because it will not fire when injecting starter fluid or mixed gas, weak spark is the prime suspect.

I have set and cleaned the points.

Should I replace the coil,spark plug wire and condenser?

Is there any way the timing can be off? It looks like the points opening match an indication on the crankshaft.

 

[racerone]

Fact-----If you have spark the timing is correct !------But spark on a plug is a waste of time as far as testing maximum ignition coil output.------When air fuel is compressed in the cylinder it takes more voltage to jump the 0.030" gap.-----Set up some means to create a 1/4" gap ( screwdriver in the plug boot ) to force the system to it's potential.