Left cyclinder not firing!

[trail rider]

ok im running 340 mains, 27.5 pilots at about 800ft. and the left cylinder spudders and pops but doesnt run.the cylinder is getting gas, and its gettin spark, i've tried switching the plugs, and still nothing. i just pulled the reeds from both cylinders and they appear normal. any help would be appreaicated. i was also wanting to try switching the reeds to see if those were the problems, but not sure if they would hurt anything. thx

[Rare Scottish Tree Badger]

i was also wanting to try switching the reeds to see if those were the problems, but not sure if they would hurt anything. thx

391636[/snapback]

You're ok to try swapping them over. ... Sounds like an air leak or lack of compression.

 

EDIT: You say you tried switching the plugs. ... Did you try switching the leads also? If the 'no run' changes cylinders with this swap, then it's a fault in your HT lead or plug cap.

 

Rare.

[trail rider]

well yea thats what i mean, i did switch the plug wires, but nuthing different happend. im going to try switchin the reeds to see if nething happends and report back. thx

[trail rider]

i switched them, put em back, and tried it... still nothing. done the compression test before i switched them and both read 118psi. also tried spraying starting fluid around the boots and carbs to check for air leaks, nuthing. im out of ideas. the left exhaust is puttin out whiteish/gray smoke every once in a while while poping like its trying to start.

[Rare Scottish Tree Badger]

A couple of things to try. ...

 

1/ Another spark plug (or swap them over) - Even though you checked for spark and saw it, when exposed to the pressure in the cylinder it may not fire if it's faulty.

 

2/ If it's not the above, then it must be fuel or fuel/air related due to all the possibilities that you've ruled out.

 

I would swap the carbs and run a long piece of hose to replace the choke hose or just plug the choke holes if poss. to see if it swaps over then.

 

Must be a carb issue. ... Is the cable working the slide?

 

The only other thing I could suggest is a leakdown test if none of the above provide any results.

 

Rare.

[sredish]

Check your CROSSOVER TUBE. Just went through the same exact problem. Evean same thread title.

[trail rider]

i figured it out! ya see my bro was workin on it before i got to it, he said that the plug was gettin plenty of spark when he pulled it. but he actually never tried switchin the plugs. i switched them and the right one stoped firing. so it was a fouled plug. lol my dad said the exact thing about the plug not firing under pressure.

 

**1/ Another spark plug (or swap them over) - Even though you checked for spark and saw it, when exposed to the pressure in the cylinder it may not fire if it's faulty.**

 

thx for ya help rare.

 

one more thing, i cleaned the plugs and put them back in and it fired up and ran fine. but when its in the powerband it spudders. is this because of the weak plugs?

Edited July 13, 2005 by trail rider

[Rare Scottish Tree Badger]

one more thing, i cleaned the plugs and put them back in and it fired up and ran fine.