wildcat doesnt run rite.. HELP - Snowmobile Forum: Your #1 Snowmobile Forum

bdavis1 · 08-14-2008, 11:00 PM

it starts up rite away and runs great with the belt off, but when the belt is on it seems to bog and has no power, heres what ive done so far had the stator checked, its perfect, new coil,wires,plugs and cdi box, have checked all the connections have cleaned the carbs, made sure the plungers were opening at the same time, made sure the oil pimp notches matched up,, use to get air into the fuel lines i fixed that, the timeing notches on the stator are dead on, i cleaned out the gas tank but havent seen if that made a difference, could it be just bad gas??? thanx brandon,

**RJ Gleason** · 08-15-2008, 08:29 AM

Clean the clutch.

http://www.snowmobileforum.com/engin...ng-advise.html

JheLrey · 08-15-2008, 09:34 AM

Rite should be spelt like, right... That will help first, then we can address the problem.

X2 on the clutch, specially the secondary.

Skligmund · 08-15-2008, 11:49 AM

Clean those clutches!

BC_Dan · 08-15-2008, 02:34 PM

And when you're cleaning the primary, look for worn rollers and worn flyweights. I had a ZR 580 that would idle and run great, would not go forward at all without dying because one flyweight and roller was grooved so bad it jambed the clutch. If it's worn, replace with a 9-post AC clutch, the 6-post comets are not near as strong and require more frequent rebuilding...

bdavis1 · 08-15-2008, 06:46 PM

clutches seem to work fine, can it be bad gas? when its not running right it smokes alot and smells like fuel. i've cleaned the carbs twice now i cant think of anything else it would be.

BC_Dan · 08-15-2008, 06:56 PM

Can't hurt to dump the old stuff and start with fresh...

bdavis1 · 08-15-2008, 09:45 PM

could it be anything else do you think??

BC_Dan · 08-15-2008, 11:51 PM

This time of year, it's pretty hard to run a sled that is adjusted for freezing temperatures. If you pull the plugs, I bet they are very black, indicating an over-rich condition. You can raise the e-clip on the jet needle a notch, that will lean the midrange, but you would have to put it back in the winter when snow comes or you will be too lean. Bad gas, marginal clean carbs, dirty clutches can all gang up on you and make it so you can't move. If the carbs are spotless and the cluthes are clean and operating correctly, dropping the jet needle a notch may help.

kccats · 08-16-2008, 06:22 PM

Hey, was just past you yesterday! I agree with BC this time of year I couldn't even get my 650 to start! I would just clean everything and get it ready and the first day it's below 40 go put fresh gas in her and see what she does! I'll look for those ski's for you, anything else?

bdavis1 · 08-17-2008, 11:39 PM

thanx kccats for looking for skis but i found some, i got it runnin again and it doesnt want to idle at all i know its suppose to idle at like 2000 rpms barely runs the recoil cylinder kinda spudders and pops, does anyone know the correct screw settings for the carbs? dont have a manual, if any one knew the settings that would be great.

p.s. my freind got his polaris 600 runnin and he was driven it in the field today seemed to run good, why wouldnt mine run then?
thanx again brandon

BC_Dan · 08-18-2008, 01:08 AM

Try one turn out from lightly seated on the air screw, that's a good initial start for most Cats with Mikuni VM carbs...

bdavis1 · 08-18-2008, 07:37 PM

ok heres an up date still wont run right idles very low if at all, talked to the sled shop they dont know wats up i suggested a bad or broken reed, they said could be they told me to put my hand in front of the carbs and if one of them is spittin fuel or air at my hand that means bad reed, what does everyone else think?? if i have to change a reed im gonna bore it possible .040 over do i have to get pipes and rejet the carbs and clutch right away or can i wait til the future to do all that?

thanx brandon

BC_Dan · 08-19-2008, 01:13 AM

WHat year Wildcat, and what engine size?

**RJ Gleason** · 08-19-2008, 10:33 AM

Set the air screws on the carbs to 1 full turn out from gently bottomed, then adjust the slide stop screws (the ones with the springs on them) in until it idles at 1800/2000 rpm.

bdavis1 · 08-19-2008, 10:54 AM

its a 1990 wildcat 650, the screw on the top where the throttle cable goes in, is that what your talking about rj??? if so those are almost all the way up already and the throttle cables are brand new! does anyone else think its a reed?? i dont really want to tear the engine down?

thanx brandon

BC_Dan · 08-19-2008, 11:13 AM

the 1990 650 engine is a piston-ported engine, not a case-reed engine, so it doesn't have any reeds. A little spit-back is normal for all piston-ported engines. The slide stop screws that RJ is talking about are on the side of the carb, it's the bigger screw with the exposed spring. The slide stop screw lifts the slide so you can set the idle. The air screw is the smaller one with the spring you can't see. The air screw controls the airflow to the pilot jet, which controls the air/fuel mix at idle.

If your shop says it's a bad reed, I would find a better shop, unless they were just throwing out ideas for you to look into...

Here's a link to a parts diagram for your sled

Alpha Sports - Arctic Cat Snowmobile Catalog

bdavis1 · 08-19-2008, 11:45 AM

then what is the reed lookin thing thats screwed on to the bottom of the jug? the arctic cat diagram on brownsleisureworld.com shows it has reeds and my 88 wildcat has reeds so im pretty sure it has reeds. i just want to make sure its a reed before i tear the engine down.

BC_Dan · 08-19-2008, 03:04 PM

I stand corrected. I looked at the diagram and did not see the reeds. They were at the bottom of the diagram. It does have reeds, although the diagram does not show very well how they are accessed.

I'll go over and stand in the corner now.

**RJ Gleason** · 08-19-2008, 06:17 PM

To get to the reeds on this engine, you will have to pull the cylinders off.
The likelihood that the reeds are bad is low as the originals on this engine are metal.

The air screw is the small one on the side of the carb closest to the intake silencer (air box). If the throttle cable adjusters are all the way up, that may also be part of the problem since the slides can not get to the bottom of the bore and it is making the engine run too rich.