98 SRX Fouls pto plug

luvsno

Member
Joined
May 5, 2003
Messages
32
Age
59
Location
Mississauga Ontario
I need help in understanding how a stator or rub through short can foul a plug in an instant and never work again. BR9ECS brand new. Driving along normal nothing crazy and misfire starts. Pull the wire off the plug while it’s running great spark across it. Change the plug and we’re good to go. Only ever the pto cylinder. Can happen after 100 km or like last night 16km. Been going on for a few years now. Haven’t put many kms on it because of this. Had a bad virbration and same thing. Sent the crank in to be fixed. Hadn’t been done yet. It was out. Got it trued and welded. Taped the harness under everything while it was out. Didn’t see any break or rub through. 13000km on it. Crank was done at 12500km. Carbs cleaned in ultrasonic tank. Set up per factory specs. Power valves clean and set properly.
I have taken the bad plug out and put it in a fine running sled within 3 minutes and it will not fire. There is no common thing I do that will make it ruin the plug. Will pull to 8500 no problem one day then next day try again and it will misfire and the plug is bad. I’m done lost all confidence in running the sled anywhere. Thanks for all help. If I posted this wrong forgive me it’s been a while.
 

Yes they are all new again. It always has spark. Just don’t know why the plug will never fire again. Once it’s dead it dead. Can’t even say it fuel fouled. Sometimes it looks dry sometimes wet.
 
the boot can alter the resistance and power that plug sees, because they have a built in fuse type resistor in the boot, to randomly drop the plug is the boot needing replaced. easy way to see is simply swap the wires as they all fire the same time on the 98-99, swap the pto boot with the center and see if it drops and ruins the center plug then.
 
Think the cdi could be doing it. I just don't get how its always the same cylinder and how the plug is junk immediately. It is a 98 700 srx, they had some issues did they not. I've never seen it but all my buds have long left the srx behind hence the Apex thinking. thanks
 
Not sure if the cdi could cause this. I don't see how it could considering all the coils and plugs have the same amount of current running through them at the same time. And you said you changed the coil packs so I doubt its the coil. Did you put a new plug boot on the new coil pack? It pretty much has to be either bad plug boot or an unlucky run of bad plugs from the factory.
 
You can drop the SRX off at my house. I will use it to fly by Apex's ! Lol

All kidding aside, maybe try swapping CDI with a know good one.
 
Thanks. I’ve swapped coil assemblies still ruins pto plug. Looking at a 2011 Apex XTX to solve the problem. Lol

your not reading what I said, go out and take the pto cylinder wire and snap it on the middle cylinder, now take the center cylinder wire and snap it on the pto…….ride the sled, does it ruin the pto plug yet? or does it now ruin the center plug??
 
I thought by physically moving the coil position accomplishes the same result. I did find a small drop of coolant on the carb heater side on that cylinder. I pressurized the cooling system but found no leaks. I'm going to order new gaskets on the airbox side and have a close look when I change them. The only other thing i've done was years ago remove the baffles in the airbox but it ran fine back then, even won a radar run after i put Boomers clutch setup in it. It'll be a couple weeks before I get to run it again so thanks for all the advice.
 


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