got engine running

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91warrior

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hello.
last night i finally got my warrior engine together since the cam bearing went out in august and pretty much destroyed the top end. i had it running for a few minutes and i took it for a ride and all was good then it shut off and wouldnt even start. after messing around with it for a half hour, i discovered the carburator boot was ripped really bad. we put some tape on it and it started again so i knew that was the problem. i might rob the one of my brothers warrior so i can finish breaking it in. pictures will follow once i figure out how to post them.

new JE piston
enginerebuild003.jpg


Jug installed
enginerebuild004.jpg


head installed
enginerebuild005.jpg


just about done
enginerebuild006.jpg


hopefully it will look like this in a day or two again
fourwheeler008.jpg
 
finally figured the pictures out. hope they are good. i found an carburator boot today off of a warrrior engine we had bought of ebay. put it on and it started right up. needs some tuning which i need to figure out but i am sure i will really like this performance set up. has better low end than before but top end still seems good. will find out when it is broke in completely. more pictures to follow
 
well engine is doing pretty good. it really pulls if rpms are off idle just a little and keeps pulling the whole way. i love this kind of torque. im glad i went with the mods i did. but im having problem with tuning. i never really did it before and just spent an hour on here looking for a solution. what im having problems with is at about 1/4 to a little into mid-range, it spits and sudders. if i run it hard, say off idle and just gun it, it wont do it. but if im not working it as hard, it spits and sputters. i hope im using the right words to describe it. im sure its not back firing. the spark plug had a little black on it, but not quite as bad as the old setup i had. any ideas? it runs great except for the one part. i moved the clip on the needle 2 positions and it didnt change anything. is it the pilot jet? any help would be really appreciated. im going back out to mess with the pilot screw. thanks
 
yea tonight i messed with the A/F screw a lot and it did not change a thing. i messed with the clip on the jet needle and it also did not change nothing. im guessing its the pilot jet, just not sure if its lean or rich. im pretty sure it has the next size up from stock in it now what ever that is. motor was build before this setup and carb has not been touched since the last setup. i have been researching this site like mad so i can fix it right the first time i actually take it off the quad. like i said before, if your not working it hard, it spits and sputters, like someone hits the kill switch real quick, but if you punch it, it takes off no problems. thanks for the reply i really appreciate it.
 
It might be too lean on the pilot. If the pilot jet is too lean the fuel screw all the way out will not get it rich enough. It doesn't work the other way around though, a too large pilot jet can still be adjusted enough with the fuel screw to make a big difference, turning it all the way in will actually stop all fuel flow.

I'm not sure that it's an issue with the pilot though, usually the pilot circuit doesn't have much of an effect above idle at all, not nearly enough to make it run horribly.

Almost sounds like you might have an air leak to me. When the intake manifold cracks, and it does on every warrior at some point, (if it hasn't happened to yours yet, give it time, they all do), anyways that crack makes them run very eratically at times and can make it real difficult to troubleshoot jetting problems because sometimes they let air in, and other times the way the vibrations resonate and the amount of vacuum in the system, they won't leak. Take a very close look at it from every angle, they tend to get a crack in the rubber right around the middle on one side or the other.

I was on my 3rd one when I sold my warrior and both times it drove me nuts because they always seem to crack after you have the carb off or engine apart, which makes you think it's an issue with the carb itself, or something internal. I spent 3 days chasing the "perfect" jetting and couldn't figure out for the life of me how my a/f ratio changed dramatically from run to run from only minor changes or none at all. Man, was I pissed when I found that was the problem. I was so pissed I literally covered it with epoxy and wrapped it tight with 2 rolls of electrical tape. That was probably just as solid, if not more, than the orignal.
 
yea from what i could find on this site i too was thinking the pilot was too lean. i actually screw it in till it just about shut the engine off but still did not make a difference.

i went through 2 manifolds on this quad already, and one was on the night i had just got it running. i took it for the first ride after months of sitting with the engine apart and just like that it died and would not try at all. it took me about an half hour to find the boot was ripped wide open and you could see through it.

i found a used manifold i had off of an engine we had bought. i really inspected, even since i last messed with it a few hours ago but i could not see anything wrong. i did pick up a new one while in town, being i did not trust this one to last long, so do you think i should just put on the new one anyways even if the one thats on it now looks good from what i can find?

one last thing is the problem does seem constant. if you have the same constant, light load at 1/4 throttle or a little more it accures. but if you jab the throttle hard, its not there. i think tomarrow i will put that new manifold on but im still thinking its running lean on the pilot, im just puzzled on why it does it at 1/4 throttle going into mid-throttle. but thanks guys, i have never messed with theses carbs before but you guys are making me feel more confidend about doing it. i will let you know what i find out tomarrow with the new manifold.
 
well today i put the new manifold on and at the same time put a 45 pilot jet in as the carb still had the stock 42.5 in. tried starting it and it took a while messing with choke but finally got it started and it ran terrrible. i shut if off and the spark plug was completely black (it was not before i tried the bigger pilot)

so i put the stock pilot jet back in with the new manifold still installed and it started and ran fine like it did before. its pooring down ran so i didnt take it for a ride but i messed around in the shop a little and it seems like it still has that problem. so i guess i have some rethinking to do to try and figure it out.
 
91warrior said:
well today i put the new manifold on and at the same time put a 45 pilot jet in as the carb still had the stock 42.5 in. tried starting it and it took a while messing with choke but finally got it started and it ran terrrible. i shut if off and the spark plug was completely black (it was not before i tried the bigger pilot)

so i put the stock pilot jet back in with the new manifold still installed and it started and ran fine like it did before. its pooring down ran so i didnt take it for a ride but i messed around in the shop a little and it seems like it still has that problem. so i guess i have some rethinking to do to try and figure it out.

Sounds to me like a fuel problem or maybe a electrical.
I would first put in a new spark plug and gap it to .030" I would then take it for a ride. When coming down in speed with the throttle off does the engine backfire? If so then for sure it is lean on the pilot. I would also check the side of the carb where the air bleed jet is. Make sure that is ok.
A way to tell if it is spark is put a inline tester on the spark plug and see if your loosing spark. I would also spray carb clean or starting fluid around the carb and manifold to see if if you have a leak.
Lastly if all this doesn't work or you still have problems check charging voltage make sure that is within spec. Then go and ohm out the ignition coil (just to be safe) and stator.
This is like a rev limiter kicking in right? Just at that throttle postion?
 
Thanks jason. as of yesterday, i put in a 160 main jet. the engine seemed to have liked that better than the 157.5. i took it for a ride, and still same problem but engine just seemed like it ran smoother so i think im leaving that main jet in.

i had the needle jet still on the richest setting and decided to put it back to stock. i take it out and it seemed fine. i let my older brother ride it and it acted up a little if you were lugging it and gun it the whole way.

so i moved the clip one more slot to leaner so see if it would clear it up completely. it seemed alright, but as it got hotter, it always seems like it is getting worse. my older brother (he owned this warrior before i got it, so its been in the family since 1997) said that he has had problems with grounds not contacting right and it would do that.

just like you said jason, i need to check my electrical system now. i dont have a new spark plug but i am going to clean the grounds really good on the engine and back at the cdi box. thats a good idea about using starting fluid so see if i have an intake leak. i wont be home this weekend so its going to have to wait till monday or tuesday. just hope i can get if fixed before i go back to college. Thanks again, you guys have been a lot of help.
 

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