Middle cylinder issue

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yamahaboy94

New member
Joined
Sep 12, 2012
Messages
7
Age
30
Location
WI
2001 SRX 700
Bought from a friend this late fall, the sled pretty much sat last 2 years started once or twice each winter. It ran good for about 8-10 miles and started to lose power and seem doggy. Friend and I did some work on it, only running on 2 cylinders. Changed coils on all 3 because middle wasn't sparking. Got it to spark and still nothing on middle. Did compression test and had about 120psi. Pulled carbs and they are clean as a whistle. We are stumped. Runs on 2, middle spark plug is dry. Any input?? Thanks
 
Clean the stator it's probably got rust on it, that might be your problem I had the same issue with a 700 SXR. Removed the recoil and I cleaned the outside of the stator with sand paper then blew it out and wiped wd40 on it to prevent it from rusting again. Worked great so I did my SRX to prevent it from happening.
 
yamahaboy94 said:
2001 SRX 700
Bought from a friend this late fall, the sled pretty much sat last 2 years started once or twice each winter. It ran good for about 8-10 miles and started to lose power and seem doggy. Friend and I did some work on it, only running on 2 cylinders. Changed coils on all 3 because middle wasn't sparking. Got it to spark and still nothing on middle. Did compression test and had about 120psi. Pulled carbs and they are clean as a whistle. We are stumped. Runs on 2, middle spark plug is dry. Any input?? Thanks
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You may want to check the exhaust for signs of a critter nest.
Did you have fuel in the center carb when you pulled the carbs?
 
Last edited:
snomofo said:
You may want to check the exhaust for signs of a critter nest.
Did you have fuel in the center carb when you pulled the carbs?
Click to expand...

Yes had fuel in center carb when pulled them. There was a couple times where it ran on all 3 for the first 3 minutes of the ride then it would drop to running on 2.
 
Might need new spark plug boots. You might be able to twist the plug wire back and forth a little bit where it connects to the plug boot and get connection again.
 
not second guessing you but you stated middle plug is dry if it has no spark and not firing the plug should be wet did you actually remove the jets (main and idle) and see if you can see thru them and run a small piece of wire thru them carbs may look clean but the jets get clogged from sitting
 
1. You changed the coils around or to three completely different coils?
2. Reused the plug caps?
3. Has the center cylinder problem always stayed in the center and not moved to a different cylinder?
4. When the carbs were out, how were the reeds?
 
Middle Sparks, fuel in carb, carb is clean as a whistle, float is set good, plug is dry. Middle cylinder problem always stayed, never have problem on other 2. Switched coils and plugs and caps around several times. Thinking the fuel is getting pushed to outside 2 cylinders and middle is sucking air.
 
yamahaboy94 said:
Middle Sparks, fuel in carb, carb is clean as a whistle, float is set good, plug is dry. Middle cylinder problem always stayed, never have problem on other 2. Switched coils and plugs and caps around several times. Thinking the fuel is getting pushed to outside 2 cylinders and middle is sucking air.
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With the airbox off try half covering the intake of the carb of the cylinder thats not firing with your hand. Does it come to life?

Sent from my VTR-L09 using Tapatalk
 
^As stated above^, or, with engine running (airbox removed), squirt some gas into the centre cylinder carb and see if it fires. Yes = fuel starvation, No = ignition issue.
 
Squirting gas right into the carb and covered the intake with hand and it still didn't fire. It's got to be a timing issue, pulling the motor to look at crank
 
Before pulling the motor, you could check the phase (crudely) by finding TDC for PTO cylinder, mark the clutch at 12 o-clock, rotate assembly and check TDC of MID and MAG cylinders to see if they are all 120* apart. Have the reeds been checked?
 
northern srx said:
Before pulling the motor, you could check the phase (crudely) by finding TDC for PTO cylinder, mark the clutch at 12 o-clock, rotate assembly and check TDC of MID and MAG cylinders to see if they are all 120* apart. Have the reeds been checked?
Click to expand...

Believe that it is out of phase, they are not all 120 apart. Problem hopefully solved, pulling the motor and having someone check out the crank. Reed's looked ok, middle one looked the worst, small chip at top but not horrible, not so bad that it wouldn't fire the middle cylinder.
 
I could be wrong here but if the middle cylinder is out of phase I would think one of the outside cylinders would have to be out of time too. Also, you can't switch the plug wires around on a 2000 and up like you could on the 98-99. Have you checked the flywheel to make sure it is not rusty? Also check the pulse line from the block to the fuel pump. If it leaks it will suck air in the middle cylinder.
 
Hopefully it's not a problem dragging this old thread up, but did you figure anything out? My 01 SRX is not firing on the center cylinder. I have spark and seems to be getting fuel. I do have the original plug boots though, so I'll probably try that first.
 
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