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1973 evinrude Norseman 40hp

M

Marty1983

New member
Hi all, here to pick your brains if that's ok, I have a non starting issue with my 40hp norseman it just won't fire, new plugs, carb clean has spark and even tipped fuel into cylinder's and still nothing, is it possible to be not sparking under compression maybe? Has 75psi on each cylinder any help really appreciated cheers
 
you might try squirting some oil in the spark plug holes and crank it over a few times.its possible the cylinder walls are dry and theres not enough of a seal to pull fuel past the reeds and into the crankcase.
 
It was stated that he put fuel into the spark plug holes I believe.----Still no barking.----This should be easy to figure out.
 
yep,sorry about that racerone.i missed that he put gas in the spark plug hole,i always shoot it down the carb throat with a oil squirt can or give them a taste of carb cleaner
 
Sorry guys just in work, yes pored fuel down the cylinders still nothing, im thinking it’s not sparking under compression I’ve taken the flywheel off and the coils look a bit burnt, are these a common problem on these old motors? All wires look intact
 
You stated that spark will jump a 5/16" gap.-----It should bark with some fuel in the cylinders.-----Or maybe wires are reversed and spark is off by 180 degrees.-----Some trouble shooting must be done.
 
I do not know what---"look a bit burnt " ---looks like.---- Any pictures of these coils ?---Model # of your motor.-----
 
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It's possible that the problem could be related to the spark. Some things to consider when trying to diagnose a lack of spark include:


Ignition system: Check the ignition system components such as the coil, spark plug wires, distributor cap, and rotor. Make sure they are all in good condition and functioning properly.


Fuel delivery: Ensure that fuel is being delivered to the engine. Check the fuel lines, fuel pump, and carburetor for any signs of damage or clogs.


Compression: If there is no spark and the fuel delivery system is functioning properly, the next step would be to check the compression. A compression gauge can be used to measure the amount of compression in each cylinder. If the compression is low in all cylinders, it could indicate a problem with the engine's internal components such as the valves, pistons, or rings.


Timing: If there is spark and fuel delivery, it could be a timing issue. The timing belt or chain may have jumped a tooth or may be loose. This can be checked by removing the spark plug and observing the piston position when the crankshaft is rotated by hand.
 
There is no timing chain on this motor.-----There are no valves in the cylinder that effect compression.------There is no distributor cap and rotor.
 
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