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.

[Baileygunns]

Clean the carb.

[big_poppa49]

but how? Not sure what to take off. Im sure if I can get it took apart then I can spray some cleaner in there. Need to be more specific on what to take off.

[Thumpin440ex]

Yeh if it was sitting that long with this new gas in it, the carb could be gummed up. Pull the bowl off, give the jets a good cleaning. Def put a new plug in the bike.


John

[big_poppa49]

how can I locate the bowl? Nothing will get out of tune or anything will it?

Before all of this and when I was riding it more frequent, it would run real smooth and idle fine with no problem.

[CJM]

Spark
fuel
air

Have you tried push starting it? If it push starts the valves/timing is off.

Change the plug

Clean the air filter with some gas if its dirty, dont need alot but cleanit off and re-oil it

Verify spark, pull plug wire and stick a screwdriver in there and put it on the rocker cover or other unpainted metal. Watch the arc from the spark, no spark no start. Bad cdi or coil.

Verify fuel is getting to the carb, take air boot off and hit the gas. Gas should shoot in the carb. No fuel, carb is clogged, accelerator pump bad, clean jets.

Verify valves in spec.Valve adjustment (http://www.atvriders.com/articles/valveadjustment400ex.html)

Generally Id change the plug first and clean the jets in the carb.

Also if its cranking but wont turn over, when its cold outside these engines wont start easily. Pump the throttle 3-5x before you crank, it kicks over your pilots too lean.

Verify timing, Using the adjustment procedure, set to "t" mark on flywheel and remove rocker cover. Cam should have lines that look _ | _ and the one line | should point up and the others be very close to even with the head.

Bowl is on bottom of the carb, remove the carb. Pull 4 brass screws on bottom of carb thus removing the bowl.

[big_poppa49]

very good info there. I will try those procedures tomorrow, starting with a new plug (probably needs one anyway) and verify spark. Then if thats a no go then I will try cleaning the carb.

You say clean the jets, where are they located? Will I see them when the bowl is removed?

[JACK STRAW]

a factory service book or cd off of ebay will help you with the repairs, with pictures and descriptions. you can generally get the cd's for a couple of bucks

[CJM]

When ypu pull the carb the jets are inside the bowel. They unscrew and you should clean them with a small wire in all the holes and douse them in carb clean.

When done blowing thru the hole air should come out all the orifices.

[big_poppa49]

FIXED! Thanks alot guys. My problem was actually the "float" was stuck thus shutting off fuel flow. I did clean jets while I was in there. Before I was not seeing fuel "spray" into carb, now it sprays like it supposed to.

Another question now that I got it running. Its running like it was before all this got started. Sometimes after running when I come to a idle it will cut off. Any help here? Remember please be specific and detailed. Thanks

[CJM]

Carb rebuild kit, float needles bad I bet.

[CJM]

Carb rebuild kit, float needles bad I bet.

Also how low is your idle, try turning the idle screw a bit clockwise (if I recall) to raise the idle and see.

Id rebuild the carb anyways, those float needles wear out cause of the rubber on the end. For the future, if your going to store or not ride it for awhile theres a flathead screw that is inline with the overflow hose. Turn it counterclockwise and it will drain all the gas in the carb out the tube.

[big_poppa49]

carb rebuild kit. Is that something I can do myself? Easily done? I have not tried the idle screw yet, I will try that first.

Also could you link me to a rebuild kit?

01' 400ex

[mrcribbs]

http://www.jetsrus.com/individual_parts/sh_03_044.html

Not difficult to do as long as you have the correct tools and some mechanical ability.