99ZR700 Runs on 1 cyl below 1/2 Throttle??? - Snowmobile Forum: Your #1 Snowmobile Forum

JonCBrand · 02-01-2005, 09:25 PM

Ok I was riding the sled 2 weeks ago I bumped the kill button and quickly pulled it out. It backfired and now runs on only the left cyl below about 1/2 to 3/4 throttle.
I put new plugs in but still acts the same.
Im thinking either I cracked a reed. OR
I had a 1996 ZRT with some sort of switch on the Carb that cut ignition when in sensed the throttle was stuck open.
Please Help me.
Jon

**smallengineguy** · 02-01-2005, 10:07 PM

Get an inline spark tester to be sure you have spark. If so, check the reed.

JonCBrand · 02-02-2005, 09:38 PM

Checked compression
both cyl 140psi on 3 full pulls (builds 90 on one pull)
Good healthy blue spark on both cyl at the same time (tested with GM HEI ingnition tester)

Im now thinking the jet in the right carb fell out. I played around with them last winter in the UP and might not have torqued the right jet in all the way.

JonCBrand · 02-03-2005, 08:22 PM

Fixed it!!!
I was overthinking the whole thing and skipped the basic checks. The #2 carb popped off the boot when it backfires and was sucking air around the carb.

kingmort · 02-05-2005, 07:10 AM

A lesson for all of us,,,a thorough , patient visual inspection is the best way to start any investigation.