98 mach z? - Snowmobile Forum: Your #1 Snowmobile Forum

airbornreddog · 01-16-2008, 03:43 PM

i have a 98 mach z 800, new sled to me last year didnt have much time to ride. i ran it some this year it would idle at 2000 and the take off at around 5000 would almost throw me off but for some reason now and i cannot figure out why its idleing at 1500 and its boggy on take off but gets up and goes when at higher speeds just wondering what the problem may be. any info would be great. thanks

**smallengineguy** · 01-16-2008, 08:27 PM

Check the spark plugs, I'll bet one of them is all wet and fouled. One of your 3 pipes is probably cold also.

airbornreddog · 01-17-2008, 07:24 AM

the day it was acting funny i changed all three plugs yet it still had no power on take off and wasnt idling right. someone told me it might be getting too much oil, could that be the problem?

RoadkillSTX · 01-17-2008, 01:48 PM

What colour are the plugs?
Have you checked for spark?

airbornreddog · 01-17-2008, 08:52 PM

the middle plug looks the best with a chocolate color and the outer two are a little black. they have plenty of spark.

**smallengineguy** · 01-17-2008, 09:04 PM

Sounds like the chokes might be sticking open in the bores of the carb. Are all the exhaust pipes hot? If one is cooler, that's the bad one.

airbornreddog · 01-17-2008, 09:06 PM

they are all hot, seem to be the same temp.

**smallengineguy** · 01-17-2008, 09:13 PM

I'd check the chokes next.

airbornreddog · 01-17-2008, 09:17 PM

well to be honest im not wrench head so how would i go about it? btw thanks for all the help on this.

**smallengineguy** · 01-17-2008, 09:22 PM

The choke cables go into the top of the carb, off to one side (not into the round thing on the very top, that's the throttle cable). It takes a 12mm wrench to loosen the brass nut thing. Unscrew it and CAREFULLY remove the choke plunger. It is a round thing attached to the bottom of the cable. If the cable won't pull out, the plunger is seized. If they do pull right out, then there is another problem.