Everything works, still no 4th cylinder!!!????!!!???

[73Satellite]

Ok, so I have air, fuel, spark to the outside left cylinder. I have tried another brainbox...nothing.

I took it for a ride yesterday and it seemed like when at 3/4 to full throttle I would have full power, but when I let off the throttle it bogs and sounds and feels like only three cylinders.

At idle I remove the coils from each cylinder and have reduced idle change and replace them and they fire, except for the ouside left cylinder. I have changed plugs, coils, and have checked for spark and we have spark.

I have cleaned the carbs and thought it may be a clogged pilot jet. I will be removing them to check that tonight. I suspect it is clear and working fine. Because when I pull the plug it is wet and when I turn the motor over with the plug removed it shoots an air/fuel mixture.

Could it be a float no adjust\ed correctly for that cylinder? And the cylinder overloading with fuel not allowing it to fire?

Any other ideas?

The previous help was appreciated....it helped eliminate a lot of possibilities.

 

[srxguy]

I know you did it but clean those carbs again. My buddy had same issue and it was a plugged pilot jet..clean clean clean

 

[black john]

4 th cyl

sounds like a stuck carb float mine will do the same thing once and a while but with my electric fuel pump its a lot easyer to find as it will shoot fuel out of the front of the carb with out runing the sled. try removeing the air box and starting it up if this is the problem you should see fuel runing out of the air bleed for the pilot.(a small brass jet in the carb bell )

 

[Convert]

I took it for a ride yesterday and it seemed like when at 3/4 to full throttle I would have full power, but when I let off the throttle it bogs and sounds and feels like only three cylinders.

Thats exactly how mine acts when I have one plugged pilot WOT she seems fine but start backing off and she misses hesitates etc.... I'm with srxguy clean clean clean

 

[kinger]

I had to clean my carbs 3 times in 1 mile to get them to run right. I had a lot of crap in the gas and finally got it all worked through. Sucks as it takes a hour to do each time but its definitly a carb issue

 

[73Satellite]

STILL NOT FIRING!!!

So I cleaned cleaned cleaned the carb on the cylinder not running. I still have fuel and spark!! Where does the pilot jet squirt into the carb? Can it be clogged that bad? What else can I do to resolve this problem???

 

[maxdlx]

Run it with the air box off and make sure the slide is moving at low rpm. Maybe a small vacum leak that high rpm over comes. Maxdlx

ps have you syncronized the carbs.

 

[Rockmeister]

Re: STILL NOT FIRING!!!

So I cleaned cleaned cleaned the carb on the cylinder not running. I still have fuel and spark!! Where does the pilot jet squirt into the carb? Can it be clogged that bad? What else can I do to resolve this problem???

Any gasoline engine needs air, fuel, compression and spark. (in the correct ratios)
You need to find out what is different in the one cylinder from the others.

Sounds like you have already ruled out an electrical problem with the spark.

How do the compression tests compare?
If they are relatively close, you can rule out a mechanical problem.

That leaves air and fuel delivery.
Air is most likely not a problem, as the engine has a common air box/intake.

Fuel delivery may be a problem, it was suggested a few days ago to see if the slides were moving properly, have you done this?

I agree with maxdlx, check the carbs. They may be clean and still have an issue of some type and not working correctly.

If you are convinced the fuel delivery is correct, its time to do a compression test and post the results.

Whatever you find, let us know!

 

[bdm]

Re: STILL NOT FIRING!!!

So I cleaned cleaned cleaned the carb on the cylinder not running. I still have fuel and spark!! Where does the pilot jet squirt into the carb? Can it be clogged that bad? What else can I do to resolve this problem???

By "cleaning" I hope you mean pulling off the carbs and taking them apart and using compressed air in all orifices and carefully reassembling. The only way to be sure that they are clean.