[ddrbass]

I have a 1972 Evinrude 50hp that does not want to start.
When the key is turned the starter spins the flywheel and the engine tries to start...sometimes. Every so often as it's spinning it will produce some smoke out the exhaust along with loud backfires. Often it will backfire out the carbs as well. It never actually starts.

---------------

Things I have checked:

Compression is 150 on each cylinder

2 new sets of sparks

Ignition system checked with a spark tester

Sparks checked

Rebuilt and cleaned the carbs

Cleaned the carbs again...4 or 5 times just to make sure.

Seated the float, cleaned the jets and all the passageways

Adjusted the needles...alot

Tuned it per the oem manuals instructions

Replaced all the lines

Replaced the impeller

Repaired a sheered flywheel key, and torqued the nut to 105psi

2 new batteries

Replaced the starter brushes twice(the springs kept melting from using the starter for so long. Lesson learned)

---------------


I have tried bypassing the carbs and shooting premix directly into the engine. It backfires the same way.

It has a 3 nipple fuel pump; when I was replacing the fuel lines I accidently switched and plugged the fuel line into the manifold instead of the carb. Then I pumped some fuel. Realizing this was wrong, I disconnected the lines and let it drain. Could this be causing my grief?


I'm running out of things to check, any ideas?


Thanks!

[tashasdaddy]

pull the plugs, and turn the motor over to get any gas out of the crank case. you either have a sheared flywheel key again, of a crossed plug wires. on wrong plug. with the backfiring, it could have sheared the key again. also those motors are very sensitive to timming. http://forums.iboats.com/showthread....d.php?t=228183

[ddrbass]

Thanks for the tips!

Unfortunatly,
I pulled the flywheel and checked the key, it looks fine.
The wires to the plugs are correct as they wont stretch far enough to get crossed.
I followed the instructions in the link but it still will not start.

Could something in the timer base or the stator have broken?

[R.Johnson]

Check the wire's from the pak to the coils', also sensor wire's to pak.