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Hello Folks,

Im new to this fourm and new to Skidoo - He Ha. It's like Im 12 again riding my first sled ( A Johnson 440 - I cant remember the year, but it was a long time ago).

I just picked up a 2003 MXZ 800 that is pretty impressive ill tell ya. Its not like the old 440 I have been used too.

Well I was on the trails last weekend and felt a little bog when I was running about 40 then she would kick in and take off like a rocket down the trail. It was about 0 degrees and I figured that maybe she dont like to go slow and thats the way these 800's are.

I do not own a owner manual - I have one ordered. I came across a topic about carb heaters. and said what is this. I looked on my sled and saw a red knob on the belt side and figured this must be a buttom to turn the so called heated carbs on and off.

Is this correct? and when should I use this. I have turned it off because it was on. Is this the reson I was getting the bog - it was also hard to start at times

can anyone explain

Thank you

Rev 420
 

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Crazy Person
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You're correct.

Do a search, we just had a couple threads on it.
 

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When the doo is hot and you go to start it.. you will find that you want or need to crack the trottle a bit.. when you pull it.. needs more air.. It is a technic you learn.. hold the trottle slightly open with one hand and pull with the other.. just when it is warm mind you..

As for the hotwater... you only want to run that first thing on a real cold powdery morning.. for about 5 or 10 minutes until the engine warms up.. then you will usually have no problems.. Maybe on a really cold day following someone in a lot of snow dust and if it starts to blubbler from icing.. you will want to turn it on... but usually you don't want to leave it on... will make the sled doggy..

Just my two cents....

Like Yellowknife said.. you can do a search and find out a lot of info on the subject.. it has been discussed in great detail.
 

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REV420 said:
Hello Folks,

Im new to this fourm and new to Skidoo - He Ha. It's like Im 12 again riding my first sled ( A Johnson 440 - I cant remember the year, but it was a long time ago).

I just picked up a 2003 MXZ 800 that is pretty impressive ill tell ya. Its not like the old 440 I have been used too.

Well I was on the trails last weekend and felt a little bog when I was running about 40 then she would kick in and take off like a rocket down the trail. It was about 0 degrees and I figured that maybe she dont like to go slow and thats the way these 800's are.

I do not own a owner manual - I have one ordered. I came across a topic about carb heaters. and said what is this. I looked on my sled and saw a red knob on the belt side and figured this must be a buttom to turn the so called heated carbs on and off.

Is this correct? and when should I use this. I have turned it off because it was on. Is this the reson I was getting the bog - it was also hard to start at times

can anyone explain

Thank you

Rev 420

[snapback]267288[/snapback]​
the manual i have states that the valve should be open when riding in deep snow conditions or when following sleds with a lot of snow dust in the air to injest. it also states "the carbuerator valve should be closed except: when riding between -5*C aand 5*C (23*F and 41*F) in a high relative humidity. or when riding in deep powder snow...or when following another snowmobile which makes snow dust." manual also states: CAUTION: when operating the snowmobile aboce 5*C (41*F) move the carbuerator heating valve to the OFF position. has a couple of pictures in the nmanual too. from experience with carbbed sleds over the years, when your riding in warm temps such as you've stated most carbed sleds will be a little boggy unless you adjust the carb needles to compensate for the temps and relative humidity. EG. drop the main jet needles to lean the air fuel mis slightly to eliminate the bog. important thing is if it gets really bad DON"T push it ...shut it off and let it cool down.. i've seen to many guy's blow a piston because they pushed it when bogging occurs. this info in the manual seems funny though eh!! you would think that you would use the carb heaters when in really cold conditions like 10 below or colder ....but!! it's right here in black and white so!!! hey...a johnson 440 eh?? been there done that....darn power packs eh!!! need anymore book info e-mail me...don
 

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REV XP Nut
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Skidoo Tech says the manual is wrong and to only use the card heaters when you have carb icing something went wrong with the French to English translation
 

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Carb icing is most likely when it's humid and the temps are right around freezing. The venturi effect of mega-liters of air passing through 2 small carbs at high velocity causes a big temperature drop, and the moisture ices up. It's not much of a problem at 0F because the air is not holding much moisture. Snow dust is the other condition that can cause carb icing.

-Don
 

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boondocker01 said:
Skidoo Tech says the manual is wrong and to only use the card heaters when you have carb icing something went wrong with the French to English translation
[snapback]268225[/snapback]​
FRENCH TO ENGLISH TRANSLATION!!!???? we have that problem with the name for the new buick we're building in oshawa....it's called the LACROSSE....but the french translation means WANKING OFF!!! so if the car is staying in canada it's labelled the ALLURE...please don't translate that in spanish!!! figures eh!! only in canada where you can't smoke a *** but you can marry one!!!
 

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REV420 said:
Hello Folks,

Im new to this fourm and new to Skidoo - He Ha. It's like Im 12 again riding my first sled ( A Johnson 440 - I cant remember the year, but it was a long time ago).

I just picked up a 2003 MXZ 800 that is pretty impressive ill tell ya. Its not like the old 440 I have been used too.

Well I was on the trails last weekend and felt a little bog when I was running about 40 then she would kick in and take off like a rocket down the trail. It was about 0 degrees and I figured that maybe she dont like to go slow and thats the way these 800's are.

I do not own a owner manual - I have one ordered. I came across a topic about carb heaters. and said what is this. I looked on my sled and saw a red knob on the belt side and figured this must be a buttom to turn the so called heated carbs on and off.

Is this correct? and when should I use this. I have turned it off because it was on. Is this the reson I was getting the bog - it was also hard to start at times

can anyone explain

Thank you

Rev 420

[snapback]267288[/snapback]​
Glad to hear youre excited bout the new sled. regarding the carb heaters, quite honestly if youre like most of us you'll never use them. After close to 10,000 miles on ski doos with heated carbs, in every temperature imagineable Ive yet to ever touch that red valve.
 

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i'm with tt on this one, have not turned my carb heaters on, ever.
 

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I thought the feature was worthless too but they helped me out a few times. Just this past year we were getting freezing rain so I believe the temp was around 32 *F. The sled idled like "edit for bad language" and ran like "edit for bad language" until I could open it up a bit. I figured the pilots had some ice build up on them. I ran it for 10-15 minutes and it didn't clear up like it usually does. I turned the carb heaters on and let it idle. Within 5 minutes it cleared up.
I also had this problem on a trip in the UP. This time I believe the pilots and mains were iced up. We left the sleds sit out in the snow for the night. The temp was about -15 *F. After the sled warmed up with the carb heaters on it ran great. 2 other guys didn't have the carb heaters and thiers wouldn't run for "edit for bad language".
 

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if you are the lead dog, you never need them... but if travling in snow dust between 20F and 35F turn them on, when it is colder than that there is no problem its just in that "semi cold" range-

and above 35F the sled will run rough and be rather hard to start when running with the heaters on-
 

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Descending doooowwwwnnnnn
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depends on where your riding and the temps,alot of my riding is off trail in powder,at -20 to -35 c...all my buds freeze up,i dont,not good when you have to whiz on your carbs to make your sled go..lol
..but for trail riding you will probably never need them.i know i will never own a sled now without heated carb feature
 

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Glad we got them up here in northern Canada,we had a few sleds run away from the rider when out in -30 -50 throttle freezing(this past week been -37 -54)even leaving them out in drifting snow will freeze the buds in a couple minutes,now we
lock the brake start up with heat on go inside for coffee and all is good.I leave
mine on the gade on all winter until spring time,tried it when hot out ,didnt run verry well bog for gas.(think it makes gas too hot) Also my 05z has the bodies heated.
 

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rev_rider19 said:
The sled runs like crap when its on and not needed, safe to say you almost never need it
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Thats very true. I believe they make less power with them on. Its probly not too noticable though. A colder, more dense fuel mixture should make more power than a warmer, less dense mixture. Thats the theory behind cold air induction kits for cars and trucks.
Carb heaters can sometimes make it tough to start your sled after its been running for a while. I think the explanation behind that is the hot/warm carb aids in the evaporation of fuel in the float bowls.
The carb heaters are a feature that is usefull maybe a hand full of times but if the time comes that you need them you will be glad you have them.
 

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REV XP Nut
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I've found below the border most of the flatlanders that use their carb heaters above -0 deg. have a hard time starting when hot , thay don't run as good and thay backfire more when they turn the engine off , course I could be Goofy
 

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i was told by a guy who has dealt with sleds his whole life. that use to own a ski doo/brp dealership,fixxed,built,and raced sleds his whole life.
that they should be 'on' when you are ingesting snow into your hood. also when it is below 15 deg or less. he also said it is because if you have h2o in your gas it can/might freeze/cause it to run lean, that the carb heaters should stop it.
so i just follew his advice. dont know if he is wrong or right but i just have to draw a line somewhere!
 
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