hard start/ starter clutch

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ifixtheyride

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Hi, new here. My problem is on a 98 warrior. I have now gone through 4 starter clutches to date. My problem started last year when I broke an exhaust valve. I had the head done and since then when I start it it turns over hard like its easy then tightens up. The motor seems to kick back and takes these clutches out. I measured compression and it was high so I took it apart and when I redone the head I also changed the piston due to damage from broken valve and I think I put in a larger piston on accident. I took the jug to a shop and had it bored and purchased yet another piston and ring. I put it all back together and it started but still didn't sound right. When it is started it is noisy and the motor sound like an explosion inside on every revolution. It then started to not want to start only when popped or if you hit throttle just right when I did get it going at idle my head pipe turned cherry red about 4 inches or so. Next time I tried to start the damn starter clutch is gone again. I have replaced the piston, rings, cam chain,exhaust valve so far. When I timed it the marks don't want to align perfect could I advance it or retard it? Do you think that could cause excessive compression or kickback? Any help would be appreciated I'm tired of spending cash on this.
 
ifixtheyride said:
Hi, new here. My problem is on a 98 warrior. I have now gone through 4 starter clutches to date. My problem started last year when I broke an exhaust valve. I had the head done and since then when I start it it turns over hard like its easy then tightens up. The motor seems to kick back and takes these clutches out. I measured compression and it was high so I took it apart and when I redone the head I also changed the piston due to damage from broken valve and I think I put in a larger piston on accident. I took the jug to a shop and had it bored and purchased yet another piston and ring. I put it all back together and it started but still didn't sound right. When it is started it is noisy and the motor sound like an explosion inside on every revolution. It then started to not want to start only when popped or if you hit throttle just right when I did get it going at idle my head pipe turned cherry red about 4 inches or so. Next time I tried to start the damn starter clutch is gone again. I have replaced the piston, rings, cam chain,exhaust valve so far. When I timed it the marks don't want to align perfect could I advance it or retard it? Do you think that could cause excessive compression or kickback? Any help would be appreciated I'm tired of spending cash on this.


Cam timing can cause excessive compression and kickback. Also Igntion timing.

Incorrect ignition timing.
 
ifixtheyride said:
Isn't the cam and ignition timed together by chain and keyway?

Yes it is but doesn't mean it can't jump time or adjuster stick while chain stretches. Also can be installed incorrectly.
You didn't by chance replace the flywheel with a different year? Was the flywheel installed correctly to the keyway?
How high was the compression? And what caused the exhaust valve to break? Let me guess, cam timing? Con-rod is good right?
 
The flywheel is from another year but like I said this is number 4 on starter clutch and couple of those came with a flywheel. Not sure how you could incorrectly install a keyway the key is very tight in the crank side and good in flywheel. The compression was 180lbs and after I installed piston and rings along with honed cylinder from shop I measured 150. I have not remeasured it again. Each time I have had the piston and cylinder off I grabbed the connecting rod and there was no movement in the crank bearings but! when I removed piston after high comp the connecting rod to piston pin was worn the piston pin actually had some plating rubbed off. I did not replace the connecting rod so it does have some slop but I had the issue before that. I did let a shop rebuild the head do you think the intake valve could be bent? The exhaust valve broke and I don't know why other then my retarted step son beat the living crap out of it everytime he rides it it broke.
 
ifixtheyride said:
The flywheel is from another year but like I said this is number 4 on starter clutch and couple of those came with a flywheel. Not sure how you could incorrectly install a keyway the key is very tight in the crank side and good in flywheel. The compression was 180lbs and after I installed piston and rings along with honed cylinder from shop I measured 150. I have not remeasured it again. Each time I have had the piston and cylinder off I grabbed the connecting rod and there was no movement in the crank bearings but! when I removed piston after high comp the connecting rod to piston pin was worn the piston pin actually had some plating rubbed off. I did not replace the connecting rod so it does have some slop but I had the issue before that. I did let a shop rebuild the head do you think the intake valve could be bent? The exhaust valve broke and I don't know why other then my retarted step son beat the living crap out of it everytime he rides it it broke.

As long as the flywheel is from a 1990 to 1998 warrior you are ok. If not then you will have a spark timing issue.
Sheared key way from under torquing the flywheel bolt and engine backfiring or key comes out when installing the flywheel are ways of spark timing getting off or incorrectly installing flywheel.
Easy way to check would be timing light and open the timing hole to check.
Exhaust valve bending or breaking is usally the first to go because the piston is chasing it in the 4 cycles(piston is coming up and exhaust valve is closing and if it is late closing, the fun begins) and most likely to become friends. Like timing chain stretch or timing chain jumping a tooth. Over reving the fourwheeler and the valve saying open would cause that. Or an oiling issue to the top of the head. Easy way to tell is if the valve guide and valve had galling. Also a worn piston pin, or busing and bearings could cause that. That would concern me and would rebush the con-rod. I suppose the piston could be installed backwards. There is so many things it could be with out seeing it or hearing more info.
 
Also replacing a used "good" part usally doesn't mean it is actually good..
Do you replace the starter gear as along with the one way?
 
The starter gear was part of the used part. The starter clutch was fine until repeated starts or attempts. It breaking is partially my fault for not correcting the main issue. The flywheel could be from a newer model I do not remember. I'm thinking of getting a pull starter. The con rod in mine did not have a bushing the rod itself is the bushing or I would have replaced it. I still think its timing. Right now it sits in the garage because I have no means to turn it over and am not sure I even want to put anymore guessing cash in it. When it is started and running the noise at idle just reminds me of a car when the distributor is not on time when you ride it it actually performs good you wouldn't even know there was an issue.
 
I now got a pull starter and about broke my wrist with kick back. Took it to a mechanic he is not familar with warrior or how hard to pull but he bump started it and think there is issue in bottom. I tore down and am thinking of splitting the cases. The big end bearing of the crank side gap is in spec about .025" gap no movement up and down. There is bluish overheating spots on the crank balancers at top(TDC area). The timing looks good. The base gasket didn't look like it sealed good between the cam chain slot and piston skirt although the "O" ring is good that is all I see nothing glaring.
 
ifixtheyride said:
I now got a pull starter and about broke my wrist with kick back. Took it to a mechanic he is not familar with warrior or how hard to pull but he bump started it and think there is issue in bottom. I tore down and am thinking of splitting the cases. The big end bearing of the crank side gap is in spec about .025" gap no movement up and down. There is bluish overheating spots on the crank balancers at top(TDC area). The timing looks good. The base gasket didn't look like it sealed good between the cam chain slot and piston skirt although the "O" ring is good that is all I see nothing glaring.

Unless you have one of the early model heads with the decomp lever, pull starting a warrior is going to be a total bitch, they don't have any kind of auto decompression like newer 4 strokes do. So yeah, it's normal for it to about yank your arm out of the socket if you don't get it started on the first revolution.
 
I split the cases over the weekend and found a bad needle bearing on one of the gear assemblies also small end of connecting rod is bad and possibly base gasket leakage not sure if I want to fix though.
 
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