Ok. I'm new to this site. But i have a 92 warrior that i bought from a friend. He said it was hard starting at times. I picked it up and in the beginning it started ok. but not great. It would crank and crank for 30 sec. to 3 monutes without a fire. then it fires once and its running. Great right!!! :atv: But about a month ago it started taking longer and longer to finally fire. Now it won't fire it all. So,,, I started with the carb. cleaned it, bought a rebuild kit and put it in. Still nothing. Then i checked the valve gap Off a little but in the range that the clymer book says. next I replaced the streched timing chain and reset the gaps again. still no go. I'm getting fuel cause the plug is wet when i try to start it. Took the plug out and checked the spark through it. good there to i think. Is there a way to check how much spark is there (voltage), and what is the optimum voltage? did a compression test on it also. 90 lbs. is that about right? Guys, I need help here!! any thoughts or oppinions are welcome. Please help me get this awsome ride back on the trails!!
warrior driving me nuts
- Thread starter Archer94
- Start date
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YAMAHAULER
Well-Known Member
compression should be at least 114lbs minimum needs top end rebuilt man not enough compression to run
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Gen1Pat
Well-Known Member
90lbs is not enough compression to start this thing right off the get. The reason you had to crank it excessively was because it had to "build" enough compression to finally compress the air and fuel for it to start. It is now at the point where the compression is so low, that it is too much for the cranking of the engine to compensate and build enough. If you tried pull starting it, it would spin the engine over much faster than the starter can it would try to, or succed in, starting. I wouldn't worry about the spark, with compression like that you need to fix it first and go from there.
Thats what i was thinking but i checked another friends warrior and raptor. Both 350's that start on the first couple of cranks. Warrior was at 80 and the raptor at 90. so i was kinda thinking something else before i sank the money into a top end kit. but didnt know where to turn. what is the optimum compression on a rebuilt motor. stock motor that is. this thing it completely stock.
YAMAHAULER
Well-Known Member
standard stock is 121lbs but a lot of people see around 140lbs after rebuild
Gen1Pat
Well-Known Member
That is way too low for any of those bikes. Are you sure the gage is accurate? Generally speaking, 120psi is the lowest "good" compression reading for a 4 stroke engine. If I'm not mistaken, 150psi is the norm for a rebuilt/ low hours engine. I picked up my engine used, and it had sat for prob a year before I got it, and I did a comp test right after I out it in the chassis, and it had 155psi. I did later rebuild it, for more power/peace of mind, and I never did a comp test. But, that 155psi turned out to be with a factory .020" yamaha piston. I know my gage is accurate, and I double checked with my fathers and there was only a diff of about 5psi. You may want to try another tester just to cover the bases. Is the tester you are using a thread in type, or a press down on the plug hole type?
thread in type. and im not sure if it accurate or not. i will also try to find a different guage system and check them again. Thank you for you input as well. sounds like the topend rebuild is the way to go. and thats what i was thinking but wanted some elses point of view before i just spent the money.
MidwayUSA
Well-Known Member
Both my 350's checked at 160PSI or above. My Raptor 350 supposedly hasn't been apart and I just did the top end on my Warrior. When you are doing the compression check are you opening the throttle wide open? Need to do that for sure as it will make a difference.
Gen1Pat
Well-Known Member
Thread in type are the best. Yes, deffinetly open the throttle. Forgot about that, thanks Midway.
DeadLastRacing
Well-Known Member
so that it sucks air in properly on the down stroke?
Gen1Pat
Well-Known Member
Not just that, but it fills the cylinder to it max/optimun volume. Gives you the best/most accurate compression readings because it has more air to compress=higher psi numbers. If the rings/cylinder wall are washed out, and you only get 90psi outta it with the throttle wide open, you know that the sealing capability of the rings is gone, and the compression is being pushed past the rings into the bottom end.
DeadLastRacing
Well-Known Member
tur dat.
But as i re-read his first post, I'm thinking his puslar coil is out or going bad. He still needs to test his stator and coil, im guessing the stator numbers will be down.
Gen1Pat
Well-Known Member
I was thinking that because if his test showed the other 2 bikes having near the same compression as his, then (theoritically) his should be fine as well. I know that the stators go out on these bikes and they are hard to start when cold, and not too bad when hot, at times... But, doing the test with the throttle open is the next step I would take. Atleast get that out of the way, then you have a better idea as to the condition of the engine.
YAMAHAULER
Well-Known Member
actually Gen it's the other way around when the stator is going it's easy to start when cold and just plain will not start when hot/warm I know I just dealt with one lol 01 or was that 2 yeah 2 the 01 and 92lmfao!!!only me killing 2 dogs with one stator haha
Gen1Pat
Well-Known Member
I thought it worked both ways sometimes. I have another friend with a wardog and his was that way for some reason. He replaced the stator and it was good. Wierd. Not that it matters... my bike runs! LOl.
YAMAHAULER
Well-Known Member
Maybe so that's just how the stators acted for me unpredictable little bastards hey
DeadLastRacing
Well-Known Member
thats how mine was. Replaced the pulsar, all has been fine!
YAMAHAULER
Well-Known Member
yeah my 92 the pulsar went and my 01 the trigger went lol so I just took the trigger from the 92 stator and wired it in the 01 stator and she runs guood!!!
