Its an 82 with tci. Spark in both cylinders. Removed left side plug and bike starts. Tried starting off the left and nothing. Left side plug is black after a minute or 2 of idle. Also i can feel heat off the right side pipe but the left is cold (with a cold feeling exhaust) New plug was installed. Any ideas? To much fuel? Carb issue?
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Left cylinder not firing?
- Thread starter alex f
- Start date
You may have seen spark, but maybe it's intermittent? Your dual output coil fires both plugs at the same time so you can swap the plug wires from side to side. I would try that and see if the dead cylinder changes sides. If it does then you most likely have a bad plug wire or plug cap, or a bad connection between them. If the problem doesn't change sides then yes, you may have a carb problem. Some causes of rich running would be incorrect float height, leaking float needle seat, or the choke not shutting off properly. In your carbs there is also a rubber plug over the pilot jet. It has to be there or the carb will run rich.
What 5twins says, you may be seeing spark, but it may not be a STRONG enough spark. Swap the leads to find out.
Is there any fuel or oil on the plug, what does it smell like? You need to do a compression test with the throttle open.
Scott
Scott
Hi alex,
low compression and black oil hints at a holed piston.
Mind you, the black oil could also say the bike is overdue an oil change.
Best case, lack of valve clearance. Head job case, burned valves. Rebore job, holed piston.
To check before pulling the engine rent a borescope to look down your plughole.
Could be carbon build up on one valve/seat, causing low compression. A leak down test could show where the problem is.
Are the valve clearances set correctly?
Are the valve clearances set correctly?
What exactly should i be looking for while looking into the plug hole? I see a build up of carbon but nothing else to mention.
littlebill31
Smells of Raw Fuel
Turn the engine so the piston begins to drop down and shine a light in there. Usually you can see a holed piston.
A compression test is needed as well as a leak down test if you feel the valves, rings and pistons are suspect.
A compression test is needed as well as a leak down test if you feel the valves, rings and pistons are suspect.
