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#2 Cylinder Dead

tboltmike

tboltmike

Regular Contributor
This is the first real problem that I had with my 1975 115 Johnnie.

Had it out the week prior to the problem and it ran with out problem. Normal RPM and speed. Started it on the hose prior to the next outing and it sounded off, but not like a miss. It started just fine. Started pulling plug wires and only #2 didn't change sound and speed. Used one of those spring adapters between the plug and the wire and attached a jumper. It would jump a 1/2 inch blue spark. The plug was cold and wet.

It would start right up on 3.

Any ideas where to start. Haven't had a chance check compression
 
Check compression first----------The dreaded broken piston ring thing comes to mind.--------------------Maybe just a blown head gasket.
 
Race,
Yeah, I dread putting the light in plug hole and looking for scratches in the bore. due to age hope it is the gasket that has given up.

Come to think of it the last two times it was out the revs were about about 300 low and about 4 mph off. Had attibuted it to extra passenger weight.

Think a leaking gasket could cause this?
 
Re: #2 Cylinder Dead, Compression Results

I did a compression test using a borrow gauge from the parts house, so I can't vouch for the calibration.

Got:
#1- 90
#2- 95 This is the one not firing
#3- 90
#4- 85

Could not find in my Service Manual neither specs for compression nor a procedure.
I put a good charge on the battery, removed all of the plugs, misted in a quick bust of Royal Purple, opened the cold idle lever all the way to fast, attached the hose and spun until the gauge leveled.

Thought about squirting in a little oil/fuel in the carb throat to see if that would make it hit. Does the top carb, port side throat feed #2?

Any other ideas?
Thanks, Mike
 
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