I've got an 88 fourtrax 4x4. It won't idle unless I have the choke about half way on. at full choke it revs really high. Other wise it just cuts off. And it runs like this whether its cold or warmed up. The fuel valve on the tank is flowing fine. A carb problem I guess? How do I need to go about trying to fix this?

 

yes the carb need's a good cleaning and i would go ahead and do a complete servicing while i was at it , but first remove clean and reoli your air filter and check for a leak in the intake tube between carb and engine intake ; you really need a good Shop Manual to do everything including checking the valve's to see if they are out of spec's !

To check for an air leak at the carb to engine intake you can use WD40 or Deep Creep and spray it in between the carb and engine intake , and if it's an air leak the engine rpms will speed up ; Sea Foam and Deep Creep are the best fuel treatment product's on the market after you get the carb cleaned and you're sure the fuel in your tank isn't contaminated with water/ trash or dead gas mix some some Sea Foam in your tank !

It's a fuel cleaner/stabilizer that clean's the entire fuel system and also the clean's the combustion chamber of built up carbon deposit's , you can get it at the sames parts stores ; i get mine from O'Reilly Auto Parts for $5.99 + tax !

The best stuff for carb cleaning is Berryman Chem Dip it's the strongest cleaner on the market , just don't get it on your hand's or on any of the rubber gasket's or plastic part's or it will eat them up ; i use a rubber Nitrate glove's that are solvent pruff or you can use a long handled pair of needle nose plyer's to hande the part's after cleaning !

And when you're done with the cleaning on the carb and part's , i use water to wash the Chem Dip from the carb ; and pour it into a pan i use for changing oil then i pour some Acetone in the same container i washed the Chem Dip from the carb and part's then put the carb and part's in and slosh it them around ; then remove them to air dry it only take's second's for the part's to dry out the water with Acetone and you're ready to put thing's back together !

One other thing i forgot to mention is before you remove the air fuel mixture screw turn in clockwise and count the turn's untill you feel a light seat ( Don't go to far or you will damage the seat ) , and remember how many turn's it took to seat ; that way you will know the reference point to adjusting the air fuel mixture screw on most carb's it's 2 1/2 to 2 3/4 turn's for the starting point !

The one Gallon size can is perfect for the carb's and small part's , jet's , seat's , needle's and other small part's , it come with a parts basket with a handle for dunking the carb and part's with ; a carb that would take a soaking over night with most part's cleaner's only take's 30 minutes with the Chem Dip !

And when you're dunking the part's basket in the Chem Dip do it in 3 to 5 second interval's , you will see the gunk melting of the carb in second's and even with the glove's i use when i'm using the Chem Dip i don't trust them completely ; that's why i said to use the long handled needle nosed plyer's !

I worked in the field of Small Engine Service and Repair Industry for over 20 yrs. and Gunk use to be a good product but the last can of Gunk it took 3 day's of soaking on a badly corroded carb and it still wouldn't come clean , i went to my local auto parts store and told then i needed something better and stronger ; that was when i first used the Berryman Chem Dip and in a little over 30 minutes the carb was clean and you acn get it in the aersol spray can Called Berryman B12 Chem Tool !

Best of luck to ya and i hope you get it going soon !.........

 

Most likely you have a clogged up slow (pilot/idle) jet. Clean the carb and pay particular attention to that jet. (Don't confuse it with the main jet!) When you put it back together, also adjust the fuel needle.

Best to get a service manual, to show you where everything is....

 

Yea I guess I should get a manual instead of going in blindly since i've never messed around with any carbs. Where can I get the manual. Is there a pdf file or anything online?

 

Make sure the spark plug it good also since so much choke has been used. Probably should just replace it with a new one anyway

----- Gimpster -----

 

Cwill15 the hardest part of cleaning a carb , is getting to it to take it off and all the vent line's coming from some of the carb's can be intimadating so it does pay to have a manual ; but in over 20 yrs in Small Engine Service and Repair i never had an up to date manual so i had to memorize how i took these thing's apart !

It sound's to me like an air leak between the carb and engine intake , to check it out start the engine and spray some WD40 or carb cleaner i would suggest Deep Creep because it's made by Sea Foam ; and is the same product as Sea Foam only it come's in a spray can and it's the best by far fuel treatment i've tried in over 20 yrs. and it been around since 1942 !

But like i said with the engine running spray the WD40 in between the carb and engine intake and it will speed up the rpm's if it's leaking , if this work's you've got a leak and you'll still need to remove the carb so you can check both carb tube's the one that goes from the carb to engine intake and the one that goes from the carb to the air box where you airfilter is located !

And if you get this far along it's easy to remove the carb from there , if you deside to try and do it yourself im suscribed to this thread so i will get an email when someone post's a reply to this thread ; and either i or someone else will help talk you through the way step by step !

There's an awfull lot of good folk's on these forums that are more than willing to help you out ; so good luck with whatevery you deside to do ; and we're all on here to help !

And you can get the Sea Foam and Deep Creep from most auto parts stores , i get mine at O'Reillys Auto parts for $5.99 + tax for a 16 oz can that will treat up to 25 gallons of gas or Deisel ; and it safe to use on both 2 and 4 stroke engine's !.........

 

Well I guess i've got the hardest part done then. I just decided to get the bike out a get it lookin and running good again. Needless to say it's took totally apart with basically the frame, motor, tank, and electrical still hooked up. I'm at school until Friday, so once I get back home i'm gonna get back to it and see if I can get everything worked out. Once again tahnks for all the help