01' 400ex won't start, plz help.

[big_poppa49]

Well can't get my 400ex to start. It was acting like it wanted to start, then would run for about 4 seconds then quit. Now it wont even try to start without shooting some starting fluid in it then it will fire but only run for a second or two. What can I do next?

Here is what I know and what I have tried. Quad has been sitting and not even started for about 10 months. Even when I ran it 10 months ago, it would run, but when I came to a idle alot of times it would cut off, but would start right back up. Since I rode it last I did NOT drain tank or do anything, I just parked it.

I have took tank off and dumped old gas out and put about 1 gal of Premium in. I have took carb off, but I have not disassembled anything or done anything to the carb, I just basically took it off and put it back on. Still having same issue as first paragraph. I did take the spark plug out and it is black pretty good. Plug probably has been on for a guessing 7 years, maybe more. I will buy a new plug tomorrow and try that, but im just wanting some ideas just in case.

What can I do or try next? Im not much of a gear head but if somebody can detail explain to me im sure I can do it.

[derekhonda]

Fresh gas (check), New Plug, Clean carb.

[big_poppa49]

thanks derekhonda. I remember you helping me out on here some years ago. Glad to see your still active on here. I rarely log in anymore, as I have got into other hobbies like flying model airplanes lol

Anywho, what do I clean the carb with and how? I dont want to mess anything up like the tune or anything. A little more specific will help me out, thanks

[Mtndew99]

What I did when this happened was bought a rebuild kit for my carb and just took the carb out took the bowl off the carb cleaned out the jets and float and just sprayed a lot of brake cleaner or carb cleaner and then put the new float pin or valve whatever you call it in and put everything else back together

[derekhonda]

For carb cleaning:

1. Take off plastics.
2. Turn gas knob to off.
3. Disconnect gas line from carb.
4. Take off gas tank.


5. Loosen the two hose clamps off both ends of the carb.
6. Remove carb from the two rubber boots. (you don't have to take off the throttle cable, just need to be able to look at the bottom of the carb)


7. Grab a rag and a screw driver. Remove 4 gold colored screws from bottom of carb. Careful, these strip easily. Some gas will spill, thank goodness you have a rag handy.
8. Pull the two jets (gold colored, I think both can be removed with a flathead screwdriver but it's been a minute)
9. Hold up to a light bulb and look through them. Chances are they are dirty and need cleaned.
10. If dirty, spray some carb cleaner in them or let them soak in a little bit of it. I hook up an air compresser and plow air through them and that cleans them out great.
11. Continue doing that til they are clean. Might as well hose all interior of the carb down with carb cleaner while you are in there (underside, and through both ends that go in the rubber boots. Work the throttle a little bit and you'll find more areas to clean)


12. Put jets back in, put the bowl and the 4 screws back on, fit it in the boots and secure the hose clamps. Set your gas tank back on and connect the gas line. I'd stop there and fire it up. With the new plug, fresh gas, and now a clean carb you can find out if it's running properly now or not.