I have a Viper that isn't firing on one cylinder. Was running good, then one cylinder quit firing along the trail. Pulled and cleaned the carbs but that cylinder is still not firing, the plug looks like it did out of the box.. I started it with airbox off and that cylinder is blowing air and a little gas back toward the airbox!? Ideas?????
jet101ski
New member
You probley have a broken reed.
-1] check compression on that cylinder[quick test would be to hold thumb over spark plug hole and crank over-you should be able to feel a lot of pressure-you can compare it to other cylinders to get a feel for what it should be]
IF LOW COMPRESSION-REBUILD
-2] check for spark
IF NO SPARK CHECK/REPLACE PLUG,PLUG CAP.+ OR COIL
-3]check reeds
REPLACE REEDS IF NECESSARY
-4]check choke function
CLEAN/REPAIR AS NECESSARY
-5] check for plugged jets or incorrect float level
CLEAN INSPECT CARBS AGAIN
IF LOW COMPRESSION-REBUILD
-2] check for spark
IF NO SPARK CHECK/REPLACE PLUG,PLUG CAP.+ OR COIL
-3]check reeds
REPLACE REEDS IF NECESSARY
-4]check choke function
CLEAN/REPAIR AS NECESSARY
-5] check for plugged jets or incorrect float level
CLEAN INSPECT CARBS AGAIN
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Good stuff, thanks!
1. Compression is good at about 120
2. It does have spark so that should be good
3. Reeds are next to check
4. Choke function is good.
5. I'll blow out the jets again, did it twice already but can never clean them enough!
How do you check/set the float level in these carbs??
1. Compression is good at about 120
2. It does have spark so that should be good
3. Reeds are next to check
4. Choke function is good.
5. I'll blow out the jets again, did it twice already but can never clean them enough!
How do you check/set the float level in these carbs??
Use the search function and type in "carb cleaning 101 with pics" mrviper700 put this together for everyone...Excellant description, we are very lucky to have guys like this contributing!!!!
Just another thought...even though you have spark ,try swapping the plug cap to another cylinder to see if the problem moves as well. The caps have resisters that some times burn out.
harness racer
New member
you have a broken reed pedal more than likely.