Mercury 1966 trouble starting

[Bankx]

I just got a mercury 1966 (200) 20hp motor. I was wondering if someone could tell what kind of spark plugs I should use. I have cleaned the carb and when I try to start it, it back fires. Please help!

 

[Laddies]

Re: Mercury 1966 trouble starting

J6C, gapped at .025

 

[JB]

Re: Mercury 1966 trouble starting

If the "backfire" is a loud bang in the exhaust you may have switched the plug wires, firing the cylinders when the exhaust ports are open. This could also be caused by a sheared flywheel key, allowing the flywheel to shift position on the crankshaft.

If, on the other hand, the engine is merely sneezing it is not getting enough fuel, suggesting an unsuccessful carb service.

Good luck.

 

[Bankx]

Re: Mercury 1966 trouble starting

If the "backfire" is a loud bang in the exhaust you may have switched the plug wires, firing the cylinders when the exhaust ports are open. This could also be caused by a sheared flywheel key, allowing the flywheel to shift position on the crankshaft.

If, on the other hand, the engine is merely sneezing it is not getting enough fuel, suggesting an unsuccessful carb service.

Good luck.

Thanks for the help! I had the wires swaped! It fired right up but you would think that the far plug would use the longer wire. Once again thanks