Chronic dirty carbs

P

Photofinish

New member
For the last several years I've pulled my yamaha rx1 2003 4 stroke out to get it ready for the season and it only runs on three or less cylinders anyone have any quick fixes on clearing them out. I'm sick of having them cleaned every year. why is this happening? Bad gas? I was told by the dealer that the reeds have tiny holes that clog easily
 
M

mxz500rider

Member
I'm sure this will stir the pot, but take it for what's worth. I had an 01 mxz 500 and an 02 edge 600 and I was in the same boat you are, tired of cleaning carbs. Friend of mine use to work at a Polaris dealer. One yr I had cleaned them and he told me that if I didn't wanna clean them again what I was to do at the end of the yr was suck the tank dry, add bout 1.5-2 gal of race fuel(110 octane), let it run till you can smell it, after that shut the gas off to carbs and let it die out. The next season before I fired the sleds up, I pulled carbs and they looked new. Sleds ran like a dream.
 
E

ezra

Well-known member
it is just your government looking out for your best interest.
carbs are carbs.like stated above drain fuel and if at all poss only run non oxi on your last tank then seafoam your last tank shut of fuel and run till it runs out of fuel
 
F

fredster

New member
I have an 07 Vector, same chassis, smaller carbed engine, and the first year I had it I added fuel shutoff's just upstream from the fuel pumps. When I store it for summer I shut off the fuel and let it idle until it stalls and I have had zero problems with the carbs - 6000 miles and 6 years and I have never touched the carbs and it runs great. The following year we bought a Vector for my son, same carbed engine and I didn't add shutoffs, we added stabil, etc. before summer storage and the next fall it would not idle, the idle jets were plugged. After cleaning the carbs we also added fuel shutoffs to the Vector and have never had to touch the carbs since. If your sled is carbed, you reallly need to use shutoffs and run the carbs dry before storing it......
 
S

scott_b

Member
I third running the carbs dry. My sons 50cc ATV will run poorly after as little as 1 month if I let t sit with fuel in the carbs. Turn the fuel off and run it dry each time = no carb problems.
 
R

reiley99

New member
went to take my wifes sled for a little ride sunday carbs needs cleaned runs like crap. i've never had a problem with my own sled with dirty carbs.Luckly I have a ultra sonic cleaner to clean them with that's one item i'll never regret getting.
 
E

ezra

Well-known member
fredster said:
I have an 07 Vector, same chassis, smaller carbed engine, and the first year I had it I added fuel shutoff's just upstream from the fuel pumps. ..
Click to expand...

are u kidding no $2 buck factory shut off on a carb sled.

I dont get it they will slap on a worthless 8 lb mud flap to cover the carbs from who knows what but no shut off?

better question why is the so called best motor in a snowmobile using a carb in 2007.
 
Last edited:
B

blkhwkbob

Active member
Yeah, it's not the reeds, it's the pilot jet, I think. If you take one off and try to look through it when it's dirty, you won't see any light. If you take a thin piece of wire, like a small guitar string and poke it out repeatedly, you will see several small holes in the end, like looking through a shower head. Then shoot some carb cleaner through and they are good to go. I have the whole carb cleaning process down to about a half hour, but it still sucks. Before I put them away this year--SHUT-OFFS will be installed!!!
 
F

fredster

New member
erza - fwiw, I don't believe any of the 4 stroke carbed Yamaha's had shutoffs.....and they were selling carbs on the 3 cyl sleds until 2008....all FI after that. To be honest, both of our carbed Yami's run fine, no plug fouling like the early RX1's on cold starts, responsive throttle and 18-20 MPG. Certainly one less concern with FI as the rail stays pressurized and no concerns with fuel evaporation in the off season, but it has not been worth it to me to spend $3-4 grand or more to trade up to the same sled new with FI. Obviously, when I do buy my next sled it will be FI......
 
J

JimAndros

Member
My opinion on this issue:

Running the carbs empty will help, but there will still be some residual fuel to evaporate. It does seem to be low enough to not typically leave problematic residues. Drain the tank and put some 100 LL av gas in & run it thru the carbs. It has a much longer shelf life.

As for the fuel valve, none stock on the Cat 570s either.

EFI is the long term answer and to meet emissions requirements, nearly all sleds will need to be EFI. Using corporate emissions averages, the manufacturers may still be able to slide in a dirty engine for the purpose of having a price point sled. But then again, as carbs become extinct, the cost to produce them & related intake systems goes up per unit.

Most simple cure if you have access to the sleds all summer long (I realize some are stored in remote locations) is to start them & let them idle up to operating temp maybe once a month.
 
R

Ricardo

Member
They don't have shut offs because the carb float bowls have drain screws! Use them and you will eliminate the problem.
 
F

fredster

New member
Ricardo, have you ever tried to do this on a 3 or 4 cylinder 4S yamaha? No way to get to the drain screws, have to pull the air box, battery and a few other things just to get at them and then I'm pretty sure you would still need to pull the entire rack to get at the drains.....30-40 minutes to R&R......using the shutoffs takes about 10 seconds......no way I'm going to pull the carbs off a deltabox 1 or 2 chassis every spring just to get the gas out........
 
S

snake

Member
like lenny said=ethynol is a big problem,esp when it sits for a time. but even with pure gas=run stabil ALL THE TIME!! I would not use sea foam if it sits at all,it contains alcohol,and alcohol by nature attracts water. I will use sea foam if I know I'm going to use the fuel in the near future.being a sled and marine tech for 30years,I have seen the problems with fuel that sits,weather its pure or ethynol. I use stabil ALL season in everthing except car or truck,it works!
 
D

dognvenus

Member
On the Mikini carbs on Polaris, would pulling the water trap plug drain the bowl and eliminating any chance of residue?
 
You must log in or register to reply here.
Top