OZ ATV :: The Australian ATV Forum

[aussietimberwolf]

Hi all,
First visit here and I have a tricky one for you. (sorry, but, somewhat long post to follow)

I have a electric start problem with my Yamaha Timberwolf 2WD 98 YFB250.
When I use the electric start (ignition on, run switch on, and press the start button), it will crank like a beauty but will not start. Sometimes however, it does start but not often. Once it does start it runs great.
If I use the pull start it will start up first pull, no problems. and also run great.
So far, I installed a brand new battery, cleaned all the connections, adjusted the inlet/exhaust valves, adjusted the carbie and used friend;y and encouraging words to it. I checked the static resistance of the coil (Mitsubishi F6T535) and it shows 16k ohms between the spark plug connector and the earth point or primary lead point. The manual says it should be only 1kohms, but if the coil is faulty, why does it still start and run perfectly buy using pull start???

Help!!

Cheers

[dangerman4]

im thinking its a poor earth to the coil, or the coils on its way out.
when your using the electric start it uses a fair bit of battery voltage which obviously drops the available volts to the coil from say 12.5volts with the pull starter down to around 11.5 volts while its cranking on the starter. add in the sus coil or poor earth and it dosent produce enough spark to start. im assuming you have tried a different plug and or dropping the plug gap down a bit?

[PeteW]

Yeah I'd be going with the coil theory there too.

also when you pull start it aside from the voltage thing, you are actually spinning the engine faster than the starter motor can spin it.
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[aussietimberwolf]

Thanks for your replys.
I rang a ATV wreckers for a coil and he asked my why I need one. I explained my problem and instantly he siad it was a fault with the stator. He said that he has fixed a few with exactly the same symptons and that is is a common problem with the 250 Timberwolfs. I have removed the stator and there was oil in the casing where it lives. Since there are oil seals about, I assume that this is a type of stator that works in oil.
I have already bought a replacement from O/S and will give it a go.
May also get a coil as well, while I'm at it.
Cheers.

[dangerman4]

well was the motor spinning over fast on the starter?
or slow and irregular?

if it was still spinning over fast then the problem is probally your coil.
however if it was turning over real slow then yes it could be your starter or your battery,
my old mans timberwolf did a starter a few years ago, but that was obviously the starter not what you have described in your first post.

[stink989]

stator dangerman not starter
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2006 Banshee
Ridden not pampered

[dangerman4]

dam beer goggles

[aussietimberwolf]

dangerman4,
On using starter the motor spins fast and regular. Starter and battery are OK.

Will wait till I get the stator and see what happens then. if it proves to not be the stator, I may have a good used one for sale.