Hello Pride,I got one that's kinda stumpin me,My daughter's 90,which is just out of warranty!,developed a problem last weekend,and i am havin a time figuring it out.what happens is after running along at cruise for around 5 minute's it loses power,like a fuel problem,it will cut off,after about 1 minute it will start back upand it will run fine,but after riding along it does the same thing,it will actually backfire then lose power and die,it's actually gottin worse every time she trys to ride,being a auto tech it act's just like a fuel starvation problem,so i started at tank and worked my way down totally disassembing everything and checking for restriction and i mean everything,no dirt or debris nothin carb was cleaned and blown out and fuel lines cked and blown out cked and cleaned air filter ,which was'nt really dirty,also fuel valve,still to no avail,same problem,i swear it act's like fuel,even seems to run hotter,like a lean mixture,I did take insert out of exhaust and found fiberglass packing built up.left insert out and still same thing,i have'nt cked spark yet,cause it does'nt act like it's losing it,but will ck out,what it acts like is a clogged fuel filter,which is clean and can be blown through easily.any idea's would be appreciated greatly,anyone experience same problem on theirs?this thing will idle forever and never die,only occurs at mid to full throttle and it loses pwr gradually not all of a sudden,if u just put around slow it's fine,crazy thing i will ck for spark next time it dies,just do'nt seem like problem to me,did ck voltage at org wir e at coil light was dim but lit like it has resistor on it.once again any help would be great.my daughter is startin to eye ball my 500 with a glaze in her eye,you know how women can be so please help.Thanks Swampkat40

 

Sounds like you checked about everything. The one thing that comes to mind that you didn't mention was the tank vent hose. It could have a restriction in it. take the fuel cap off and see if you can blow through the hose freely. Other than that maybe it could be getting hot. It may have some mud stopping up the cooling fins on the motor behind the shroud. Good luck and be sure to let us know what you find out. I just got my daughter a slime green 90 this weekend. It is doing great so far. After I took the clutch limiter out of it.

 

I had a similar issue with my 500 4x4 (98). It metered fine (tests from the service manual) but when i ripped the wiring harness apart it showed one corroded lead, going to the CDI heh. This also caused the battery to flatten over time. Looks like you checked every thing, hows the main jet look, isnt that for that throttle range?

Mark

 

I had a similar problem with my cat 300, here is what I did to fix the problem:
1- take the gas tank off.
2. remove the tank valve. (the on-off-reserve valve assembly)You can remove it by taking out the two screws that go into the tank.
3. My problem was the rubber filters that are located on the end of this assembly which goes up inside the tank. The rubber was clogged not allowing fule to flow. Clean or replace.

I hope this helps, it took me a while to figure out that this was the problem, but once I did, I have had no futher problems.

Cat300

 

thanks guys for tips,hoses all clear,tank valve taken apart and cked, all clear no mud nothin,crazy darn problem,let me run this by ya'll.the only thing that raises any suspision is the exhaust,this thing has fiberglass caked all up inside it at tailpipe,i don't see any plug on exhaust to remove to blow out.im thinking maybe whats happening is when running wide open these fibers or maybe whole mat is choking off exhaust,causing loss of power,then after cutting out mating falls away from opening and off she goes again.well i'm going to ck it out now!can't hurt to ck.i'll keep ya informed.later swamp!

 

Sounds good to me swampcat. I have heard of the spark arrestor being stopped up but any other part of the pipe. I would say it is as good a choice as any.

 

nope ain't exhaust,i dropped pipe and busted down our road wide open,you know something?that damn thing seems alot louder at night than during the day,it was kinda funny,goin down the road not one light in any of the houses on our [DIRT] road were on,going back was a diffrent story...hehe.looked like a block party.buddy of mine said it sounded like a low flyin ultralight.they all know me so i won't be killed tommorow,anyway i swear this things running out of fuel,you can putt around with no problem,then as soon as you gas it open,it will slowly lose all it's ummph and choke down and die,as soon as you let go of throttle while it's still running it acts like it rights itself and u can take right back off,fronts hangin,i'm missing something.i even stepped needle up a notch for s**** and giggles [nothin works]ARGGGGGGGGGGHHHHHHHHHHH.I CAN FIND A SHORT IN 11 MILES OF WIRING ON A 50000 DOLLAR LEXUS AND CAN'T FIX A TAIWANESE QUAD,go figure!oh yeah,it has good spark after it dies,and fuel in filter,also opened float drain and fuel came pourin out tube i'll search more tommorow,day off,gotta put cyl head back on jeep first,since it's much easier,won't kisk my a$$near as bad as this thing.im surely missing something.fill ya in later swamp!

 

Does the atv start back up when it dies? Have you attempted to run it with the gas cap off to allow for the tank to vent? I agree with you it sounds like its starving for gas. It sure sounds like the problem I had with my 300 but sounds like you have checked the rubber filters in the tank. You might try removing them entirely. The problem I was having was that they were colpasing (bad spelling) and not allowing fuel to flow fast enough and the unit starved for fuel. However when you let it set it would start back and run for a short distance. It could still be in the ignition unit as well, however I would keep looking at the fuel situation since I believe your on the right track. Let us know what it was when you find it.
cat300

 

How about the float level? It could be a bad float also. When you get on the gas it runs fine until the bowl is empty then dies this could be your problem. If it starts back up after a small amount of time. Try checking the carb again the float could be binding or the tab that adjust the level could have gotten bent when the bowl was reinstalled. I agree it sounds like a fuel problem.
Just a thought how about the oil level has it been going down? If it is not putting enough oil in the system it could be getting hot and just stopping before it is siezing. I don't know much about these oil injection systems but have heard of a few having problems.

 

thanks for reply mudcat,i removed float twice and found it to be in good shape and cked it for damage,i found no problems, no sticking,fuel leakage inside float.nothing.also i thought about oiling problem but ruled it out,i removed carb intake and looked at cylinder walls with borescope to ck for damage,found very little wear,just normal piston scuffing,but no grooves in walls that would indicate lack of oil.i let my daughter ride it yesterday around the farm and she had no problems,other than just felt a bit sluggish after criusing ,but it never died.this problem is really weird.you would think as simple a design and only 1 cylinder it would be easy to pin down.as soon as i get time after work tomorrow,[yes i have to work on sunday]which i hate,i,m going to rig up a remote gas tank and bypass everything but carb,of course, and then see what happens,this will rule out alotof fuel system.i'll keep you posted,swamp.