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Fuel in the air box?

B
Feb 28, 2011
15
1
3
I've got a 1999 RMK 700 which is using tons of fuel (like 7 miles to the gallon) and it seems to be ending up in the air box. The sled had a huge leak in the rubber carb to engine gasket which I just fixed but it still is pumping mist out the wrong way from the carb when the air box is off.
Also the air lines out of the air box are all disconnected and plugged. No idea how they go together as I don't have a manual or a dealer anywhere close.

The sled also bogs or misses above maybe 7000. It has the stock jets 185, but a 4" can on it. I'm at sea level and everything else looks like it's set right.
It's new to me so I'm just trying to get it running good. Not familiar with the reeds. Any ideas? I'm stumped. Plugs seem good, maybe a little rich.
 
F
Nov 26, 2007
584
153
43
Minnesota
Where are you located?

You have major issues with your vent lines and carb settings as this sled came with ACCS. If it is removed and the vent lines are hanging open then you are going to be way rich, if they are plugged then the carbs have no signal for the floats and I don't even know what that would do but I bet it aint good.


You should buy an airbox from an XC 700 in the 1999 or 2000 years or modify your existing one. It will have the holes already in it for the vent line nipples, or they may even be there if you buy a used one. Next, on the right carb (when sitting on it) there is an extra vent on that carb that used to go to the ACCS. Plug that one, then vent the rest of the lines to the airbox. Look at an XC 700 to see how it should look. At sea level, the jetting should be 180-185 and will be safe to 5 below zero. Buy some 1371G needles and set them in the 3rd position, also get some 38 pilots.

Next get some new clutch springs and go through them clutches.

If this is more than you can do mechanically and if you are near Minneapolis, I can help you, otherwise there are many snowesters that are willing to help.
 
C
Jan 25, 2011
284
16
18
south lake tahoe
I was just adjusting the carbs on mine and noticed gas blowing back out of the carbs. (I had the airbox off). The throttle was stuck open just a hair, keeping the slides open. Just something to check out.
 

retiredpop

Well-known member
Lifetime Membership
Jul 3, 2001
1,350
295
83
Calgary
You could have a broken or chipped reed petal that is contributing to the blow back of fuel into the airbox. You should pull them and have a look at them. That being said though you will always have some fuel coming back out of the carb. The airbox contains this mist and will suck most of it back in on the next intake. A boost bottle will clean that up quite a bit for you. These sleds like their fuel though. I only got about 8 miles per US gallon on a 99 600 so 7 mpg on a 700 doesn't seem too bad. If you ride at sea level then you don't need the ACCS hooked up but need to vent the carbs to the airbox like Fez mentioned. Check or change your plug wires and caps as they could be the cause of the high speed miss.
 
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