bluemonster1
LIFE MEMBER ONLY ONCE!!!
Took them off my 4-stroke 700 Maxim.Left is #1,then 2,3 and 4.Why is #2 plug so dark.Sometimes when I start the bike,#2 doesn't always fire.If I pull the boot off and slowly go back to the plug..it starts firing and then I push the boot on tight.
Does it suggest that pluig ain't firing all the time or what?????
Does it suggest that pluig ain't firing all the time or what?????
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bluemonster1
LIFE MEMBER ONLY ONCE!!!
These are brand nw plugs by the way also. Those are new ignition wires and boots also. What gives?????
What gives?????
you most likely have an ignition problem. I am assuming that this bike is a mid 80's bike? if so, the spark plug wire for that cylinder could be damaged and/or worn out. Call your local shop and ask them what the Ohlm reading should be for the plug wires and then check that wire. Also, inspect the boot and compression fitting that attaches to the plug to make sure it is not damaged and makes good contact with plug. If everything checks out with the plug wire and then work your way back upline to the coil pack. Take it off and have it tested by your local shop to see if it is putting out the right voltage or they may be able to ohlm it to see if it is damaged as well. If all is good with your ignition system then you need to start looking internally at that cylinder. Have you ever done a compression test on this cylinder? It may be that you have more of your air/gas charge going by the piston and there is so little charge left in the cylinder along with very little compression that the cylinder is not firing.
Mills
Mills
no1chevyboy
New member
i would look at the float/carb on that cylinder, do leak down test on all cylinders,stuck rings,bad valve seal, it doesnt look wet to me in pic so its fireing, but my have leaky needle (rich) or leaky valve seal but if its not smoking at all, id lean toward fuel leaking in past the needle or thru enrichener (choke) just a guess trying to help
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Answers by YODA: Yamaha Operational Diagnostic Analysisbluemonster1 said:These are brand nw plugs by the way also. Those are new ignition wires and boots also.
Hmmm. Shinny new part, but no closer you are. Problem before, existing this was. A thousand words your picture does say. Background without, answers further away.
no1chevyboy
New member
lol yamer true is
bluemonster1
LIFE MEMBER ONLY ONCE!!!
YIKES!!!!!!Might have something to do with the coil pack.Sometimes,but not always and not lately also..but # 2 and #3 weren't firing in the beginning.Now the wire for these 2 cylinders do go the the pack on the right side.I checked it last week,took cover plate off and noticed the ground wire I assumegoing to one of the mounting bolts was loose.The bolt needed tightening and all seemed better after that.I probably will have to check the ohlm's for all the wires and see if they are consistent.I have a meter,but how or what is the procedure to check the wires.
I had all plugs removed and plugs inserted into each one and tested for spark.All plugs are firing.Compression is good on the motor,I'll get some numbers on them soon.Motor still starts good and runs good on the HWY anyways.It is a 1985 Maxim 700 by the way Mills.Carbs were all cleaned a few weeks back,after sitting for 5 some years.Started up then in 15 seconds with fresh fuel in the tank.
I have a laser heat sensor and will check the temps of each cylinder and or exhaust pipes at each cylinder to see if there is a huge difference from one to the next also.I also am going to switch plugs around to see if it is a plug issue.They are all brand new plugs in there and all new wire sets also.I changed the wires 5 years back just before I parked the Bike.
I will investigate further,but Bike still runs good after a warm up.
I had all plugs removed and plugs inserted into each one and tested for spark.All plugs are firing.Compression is good on the motor,I'll get some numbers on them soon.Motor still starts good and runs good on the HWY anyways.It is a 1985 Maxim 700 by the way Mills.Carbs were all cleaned a few weeks back,after sitting for 5 some years.Started up then in 15 seconds with fresh fuel in the tank.
I have a laser heat sensor and will check the temps of each cylinder and or exhaust pipes at each cylinder to see if there is a huge difference from one to the next also.I also am going to switch plugs around to see if it is a plug issue.They are all brand new plugs in there and all new wire sets also.I changed the wires 5 years back just before I parked the Bike.
I will investigate further,but Bike still runs good after a warm up.