One cylinder only in 9.5...

woody74

Seaman Apprentice
Joined
Jun 12, 2005
Messages
47
My 68 johnson 9.5 is only running on one cylinder apparently. I say this b/c I pulled one plug while it ran and it kept running and then reattatched the plug wire, then pulled the other and the motor shut off. I fired it again(all onnected) and it ran but still only on one cylinder. Where do I start troubleshooting? I figure it is the coil for the lower cylinder but I'm no expert. with the cowling off and flywheel off which coil goes to which cylider? And then furthermore how do I get the plate off that the coils mount to in order to change the plug wires. I know how to use a meter but I just dont know what Im looking for. Please help. -woody74
 

RPJS

Lieutenant Commander
Joined
Jul 29, 2002
Messages
1,572
Re: One cylinder only in 9.5...

Undo the four posi drive screws nearest the crank shaft and the plate will lift off, then just follow the plug wires to identify the coil
 

Paul Moir

Admiral
Joined
Nov 5, 2002
Messages
6,847
Re: One cylinder only in 9.5...

Look for cracks in the coil's insulation or the spark plug's insulation. Don't bother with the meter - you won't need it. You can swap parts between the halves to 'prove' they're good like the condensors and ignition coils.<br /><br />The coil that is usually closer to the front (carburetor) side of the engine runs the top cylinder.
 
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