1986 ATC 250R...wont start...help!

[J9reaper]

107799Here is the deal, when I bought this 250r it started right up. It ran a few minutes then ran out of gas. I loaded it up took it home.....wouldnt start, tried for about an hour to start and then decided to let it sit overnight (maybe flooded). Ok next morning same thing, wouldnt start. I took it back to the guy I bought it from, he cleaned the spark plug ( it was fouled like crazy) ...started right up ...3 or 4 times in a row but would not idle. So I took it home once again. Guess what would not start..cleaned spark plug again, was clean this time, put it back on and tried again and nothing but gas out the overflow tube on the carb! Let it sit overnight and would not start the next morning. I went and bought new a spark plug, exact same kind. Replaced the old plug with the new one and still nothing. I'm not a mechanic and I have never owned a 2 stroke before. A run down of what I have checked and or done is.....put new properly mixed fuel in (prevoius owner said 44:1 becouse of the alluminum head and bored 30 over) , new spark plug, check airfilter, checked all the hoses to make sure they were all connected as best I could tell anyways, ordered new on/off ignition switch (just in case). Im kinda at a loss here...and to make matters worse my wife told me not to get it in the first place...and now it wont start, so I gotta prove her wrong now guys!! Any suggestions would be greatly appreciated.

[D-dub]

Check compression. Then go back to all stock settings, Carb and airbox. set your float height. and clean your petcock. check your reeds

[3wheelrider]

-welcome, It ran out of gas in a few minutes? You mean the tank was empty? 1st off you should never run them out of fuel.... very bad.- Well since you just got it its tougher to say. Anyway,- sounds like the float/valve sticking?(since it ran out of fuel -or may just need cleaning)- Maybe from not being used much recently. I would dump all the fuel, clean the carb,- maybe new carb kit if necessary(float valve). But that being said , I would also start with a compression check.(should be about 172-199 psi). Do all of this stuff at the same .(would be easiest). I would run a tad more oil to the mix also. 32:1 with good oil (bout 4oz.-per gallon) -then go from there. good luck.

[Dirtcrasher]

44:1 is pretty lean. Has it sat un-started for a period of time?? Sitting can dry up the crank bearings/seals, only a leak down test will show that but one of the 1st things I do is remove the stator cover and see if there is any up/down play in the left crank bearing. It's just the easier one to get to......

If you haven't, I'd take out every jet from the carb and spray carb cleaner and compressed air through it. If kicking it over blows your thumb off, your probably OK for compression if you don't have a comp tester. You HAVE to take out every jet and get it spotless INSIDE, the heck with what it looks like outside.

I'd splice in an inline clear fuel filter too.

Did you remove the petcock and clean it? Just 2 screws will show you whats been in the tank....... IDK if the on off lever comes off but I clean that too as well as the bowl which should come off with a 10mm wrench.

Put in fresh gas, mixed 32:1 and a new spark plug. Make sure the AF is cleaned and oiled.

If it keeps fouling plugs it's too rich or getting oil from right crankseal (which is the wrong oil for pre-mix). Is it oozing oil out the pipe connections?

If all thats OK, I'd measure my ohmms on the stator wiring.

The on/off switch only grounds one lead to your handle bars. So if it's got spark, it isn't the switch; At least you'll have a brandy new switch :D

Spark, fuel, compression and ignition at the right time should start it. 2 strokes are easy to diagnose. Thumpers have a bit more to them. for guys with little experience.

Asking the previous owner allot of questions may help. Sitting, last rebuild, has the carb ever been touched, main bearings ever replaced etc etc etc, can reveal allot to go on.

Keep us posted and ask for a free manual, Monroe Mike hooks up most everyone on the site with a download factory Service Manual for your model.

[J9reaper]

Well I finally got it started and took it out for a ride. Runs great!!! Well after posting this I saw that some guys give it some throttle when starting and that did the trick. I was thought that would flood it so never tried that. As far as the oil gas mixture goes I should use a 32:1 ratio instead of a 44:1? Thanks for all the info and fast responses!! So where or who do I talk to about the manual to download?

[MonroeMike]

Look here.
http://72.52.143.80/~trikes/atc250r_85-86_servicemanual.pdf