I have spent countless hours searching forums on the issues. Just to realize not many people have come back and posted the solution. I was driving a warrior I just purchased cheap (1996) around. Out of nowhere the idle started getting rough, then the engine would hardly rev anymore. I limped home and shut the engine down. Now it cranks and cranks but won't fire. I have spark, fuel, and air and compression. (Did not check timing. As I have not got that involved yet). Everything I have read is that it's pointing to the stator or pickup coil as they are a common source of failure on these machines. The guy I got it from said it was replaced a month ago With an eBay part. Has anyone seen faulty replacement stators or pickup coils fail that fast ? I ordered the coil and stator again and will see if it fixes the issue. Then I guess move to cdi and rectifier. It's just crazy to me that after what seems like 1000s of posts with the same issue that no clear resolution has been posted. Any help would be appreciated.
Cranks but won't start
- Thread starter NFryan
- Start date
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alex456123
Well-Known Member
Intake boot between the carb and motor.
I bet it is ripped.
I bet it is ripped.
Thanks for the response man. I just checked it now. That boot appears to be the only new part on the quad and it looks good. The boot was off the air on side a bit though. She still won't fire. Just watched a video on checking the timing. I'm going to check that next. As long as that is good I'm assuming the previous owner just may have gotten a bad stator. I have a new one on the way. I will report back.
So Im currently waiting on a flywheel puller. When I line up the T on the flywheel with the mark on the case. My piston is not at TDC and my timing is off by 45 degrees. I found TDC by removing my spark plug and putting a thin screw driver down the spark plug hole and cranking slowly by hand, then set the cam as per the markings.. She still will not fire over.... Im guessing my woodruff key may have snapped and the flywheel spun.. Im not sure at this point.. I will report back once I pull the flywheel.
alex456123
Well-Known Member
You would be correct with the woodruff key then. That was going to be my next suggestion. Lol
Warrior1996
Well-Known Member
It seems fairly common. Just make sure your keyway on the crank and on the flywheel is not damaged and install your new key.
So got the flywheel puller, and my worst suspicions confirmed.. Woodruff key snapped due to the starter clutch bearing basically falling apart. So I have the woodruff key and starter bearing on order.. I have a question about reassembly..
1)How does the flywheel go back on .. Just line it up and hit the flywheel puller tool with a hammer lightly? And how far on the spindle does it go?
Also the bigger question I guess is.... I lined up my timing marks on a flywheel that was way offf.. And set the cam timing to a insanely off crank pulley.. I hand cranked the motor before trying to fire up..
2) Could my attempts to start the quad several times have destroyed my engine.. No clanking or metal hitting metal noise when i was cranking.. Just a few huge backfires... What are the odds that my piston and valve train is unaffected currently.. I guess the motor initial shut off because of the flywheel moving.. so timing was ok at the moment it died...
Im hoping this is going to turn out ok without a top end and or valve job...
1)How does the flywheel go back on .. Just line it up and hit the flywheel puller tool with a hammer lightly? And how far on the spindle does it go?
Also the bigger question I guess is.... I lined up my timing marks on a flywheel that was way offf.. And set the cam timing to a insanely off crank pulley.. I hand cranked the motor before trying to fire up..
2) Could my attempts to start the quad several times have destroyed my engine.. No clanking or metal hitting metal noise when i was cranking.. Just a few huge backfires... What are the odds that my piston and valve train is unaffected currently.. I guess the motor initial shut off because of the flywheel moving.. so timing was ok at the moment it died...
Im hoping this is going to turn out ok without a top end and or valve job...
Warrior1996
Well-Known Member
For re-installing the flywheel, just line up the keyway and slide it on. The flywheel is matched to the tapered portion of the crankshaft, so just seat it lightly by hand and then when you put the bolt in the end of the crankshaft and it will be held tight (obviously the splined spacer/bearing support thing is on the crankshaft as well). Make sure you torque this bolt as well. My theory for the keys shearing is that this bolt loosens, and then the flywheel slides on the taper, which shears the key.
As for the top end, obviously the best inspection would be to pull the head off. Honestly, you already have the flywheel off, this might just be the best option. However, there's a few things that come to mind that you can try to check the motor without tearing it apart. 1) Do a leak-down test (maybe a compression check too, but that's not as useful), this will let you know if you bent a valve and it's not sealing well. 2) If you have an inspection camera, try to look down the spark plug hole and see any signs of valve-piston contact.
As for the top end, obviously the best inspection would be to pull the head off. Honestly, you already have the flywheel off, this might just be the best option. However, there's a few things that come to mind that you can try to check the motor without tearing it apart. 1) Do a leak-down test (maybe a compression check too, but that's not as useful), this will let you know if you bent a valve and it's not sealing well. 2) If you have an inspection camera, try to look down the spark plug hole and see any signs of valve-piston contact.
alex456123
Well-Known Member
I don't even think these are interference engines in stock form.
Lots of people shearing cam pins after rebuilds with no valve contact.
Lots of people shearing cam pins after rebuilds with no valve contact.
Thanks for the quick responses and info guys. I Did do a compression test before discovering the flywheel spun and it said 80psi. But I also changed the timing at that point and it is not currently correct. So It may not be reflecting an accurate reading. I ordered the starter bearing and will put it back together Friday night after setting the timing correctly. Then I'll give it another compression test. I'm hoping not to have to go any further with this.
Warrior1996
Well-Known Member
Good point Alex, I was assuming it was an interference engine in stock form. Not sure if it is or not...
So I finally got everything timed correctly and reassemble.. My compression at WOT was 180. so Im assuming I have a high compression piston.. I was able to get it to fire over and run as well. So far everything seems to be OK no damage done..
alex456123
Well-Known Member
Take out the spark plug and look into it with a flashlight at bottom dead center.
It will say 1uy if stock, if high compression it will have a big hump in the middle and a few numbers on top that will tell you compression ratio and bore size if you look it up.
It will say 1uy if stock, if high compression it will have a big hump in the middle and a few numbers on top that will tell you compression ratio and bore size if you look it up.
Thanks! I will check it out. Just glad everything is working again!
