XLT not running on all 3

[GHeTTo JOe]

i have a 93 xlt 580 sks with around 5500 miles. it ran good last year, cleaned the carbs this year and she seems to not run well on the middle cylinder, pull the plug off while running and can tell a miss. it has 120 compression with the other teo at 115 and 125. it is gettin spark, even swaped coils around and new plugs, getting fuel even swapped carbs around, still on the middle cylinder, anyone have any ideas?

 

[manowar]

that is odd for the middle only to be bad i had a 97 xlt i worked on that spun the crank and missed on the pto cyl. check the crank with a dial indicator in the spark plug hole turn the crank and the top dead cinter should be 120* apart on the 3 cyl.

 

[skis_n_skid]

Did you check the carb boot for cracks?

 

[GHeTTo JOe]

With the dial indicator your mean that TDC for outside cylinder to next is 120 degree and to the next cylinder 120 degree?
would the cracks be obvious ? or too small to see?

 

[manowar]

With the dial indicator your mean that TDC for outside cylinder to next is 120 degree and to the next cylinder 120 degree?
would the cracks be obvious ? or too small to see?

yes that is right 120 apart. they dont crack they spin on the pins by the webs

 

[skis_n_skid]

would the cracks be obvious ? or too small to see?

I assume this is in reference to the intake boot for the carb. If you grab the boot and flex it you should be able to see if there is any dry-rotting/cracking.

 

[GHeTTo JOe]

i had gottin most of the old gas out and put fresh in i was so frustrated i clean the carbs again. JETs had gotten clogged already!

 

[sodfarmer]

Have you made sure your throttle cable is connected to the slide? My buddy had the same issue and it took us 3 rides to figure it out. Got the cable hooked back up and it ran like a top.

Good luck.