Hot Exhaust pipe

O

obob

Member
My friend bought back a 99 Polaris xc 600 he used to own .
2nd owner didn't take much care of it/ been giving it some much needed TLC.
2nd owner did say the exhaust had gotten cherry red at some point.
haven't found any Vaccum leaks on carb boots or Vaccum lines, but does seem to be running hot.
No temp light coming on.
I Rebuilt the water pump, just ordered thermostat.
Hoses and coolant in bottle don't seem to be getting warm, so that's why we ordered thermostat.
It was spiting, spuddering, and poping at idle after about a minute of idling. thats gotten better.
it runs real good when up out of idle riding it.
but that exhaust pipe defintley seems to hot.
Just also ordered Exhaust manifold gaskets and exhaust donut.
piston tops look dry and black. spark plugs dry, not chalky or white.
No VES valves, no throttle position sensor on this engine.
It does have a fuel primer, touchy easy to flood one pump to much.
we also changed the Mag side crank seal when rebuilding the water pump.
Just really concerned with exhaust pipe heat.
Any thoughts?
 
K

kraven700

Member
Exhaust is glowing because too much raw fuel

Clean carbs

Crud in needle and seat allowing excess fuel to pass through

Or floats stuck or bad (unlikely but possible)

Also

Open drain plugs if front of engine case

Raise rear of sled

Crankcase probably has raw fuel in it
 
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E

euphoric1

Well-known member
You said "runs good when up out of idle" I agree 100% CLEAN THE CARBS!! I think however (and not to disagree with you kraven700) you more likely have a lean condition causing "red hot" exhaust pipe and you did not say how it does run at idle but... If the idle/pilot circuit is restricted it will cause a lean run condition giving you the dry chalky look and also the red hot exhaust, dont quote me but if I am not mistaken the idle/pilot circuit is in play up to quarter throttle and maybe a little beyond. When you remove carburetors pay special attention to and remove the pilot jets, dont just blow through them while in the carburetor body and also make sure any air bleed jets if equipped and transfer ports located in the air horn of the carburetor are clean as well. If you have any access to anyone that has a heated ultrasonic parts cleaner this is the best way to really "clean" carbs. If you are anywhere near me and can get me the carbs I would be willing to clean them for you.
 
O

obob

Member
euphoric1,
I appreciate the cleaning offer, But I live in Baldwin now, used to live in Howell.
I agree with you both, those carbs need cleaning.
I know quite a few people here, maybe someone has an ultrasonic parts cleaner.
I have cleaned carbs before, but that was more with sprays and blow gun.
I will do a more thorogh job & remove those jets when i clean them.
thanks to both of you for replying with good advise!
 
T

toddspolaris

Member
I have the exact sled and same thing happened to me, all the internal parts of the carbs have residue left behind from the ethanol in the fuel, you can’t see it but it’s there, carbs need cleaned
 
T

toddspolaris

Member
Use pipe cleaners , spray with carb cleaner and pull through the main jets and jet needles, then wipe down the needles, you'll be good to go
 
G

garageguy

Well-known member
I had an E clip come off the needle once. Ran the same way pipe got so hot it started the hood on fire.
 
O

obob

Member
Cleaned carb's, Changed Thermostat, put new exhaust manifold gaskets and donut.
Runs great! temp is good.
However the snow is Shot!
 
O

obob

Member
euphoric1,
On my sled 02 700xcsp Mikuni carbs, I thought i would clean them.
But they are much more intimidatingly, Pulled them off, removed float bowls and cleaned the two jets in there
but not the needle. Afraid to take it apart any further. also removed the jet in the air horns and made sure they were clean and their passages.
any thoughts about these carbs ?
 
mezz

mezz

Well-known member
obob said:
Cleaned carb's, Changed Thermostat, put new exhaust manifold gaskets and donut.
Runs great! temp is good.
However the snow is Shot!
Click to expand...
Good to hear. We have plenty of good snow up here though.
 
E

euphoric1

Well-known member
obob said:
euphoric1,
On my sled 02 700xcsp Mikuni carbs, I thought i would clean them.
But they are much more intimidatingly, Pulled them off, removed float bowls and cleaned the two jets in there
but not the needle. Afraid to take it apart any further. also removed the jet in the air horns and made sure they were clean and their passages.
any thoughts about these carbs ?
Click to expand...
Flat slides... Great carburetors! can seem to be intimidating but really aren't, no different that round slides as far as what jets to remove and no different that the round slides to make sure passages are clean and clear. I would still recommend removing slides and cleaning the jet needles and tubes. Watch the o-rings on the float assemblies can tend to leak over time. Just like anything else watch how it comes apart, there is really no need to completely separate the carburetors. Make sure again to pay attention to the transfer ports and jets in air horn like you mentioned and the pilot jet and circuit. Im not a big fan of aerosol carb cleaners as they just aren't as potent as they used to be and with the ultrasonic cleaners you get deep into the internal passages in the carburetor,
 
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