2000 Yamaha Kodiak 400 won't start

[Shadowace]

2000 kodiac 400 bought for wife no issues in 2 years , she shut it down after riding an hour and it wouldn't start .

Cranks over but no go. Towed it home

Took carb of cleaned it no start.Took out plug held against frame orangy spark.Put in a new plug and realized the electrode on the old one was bent .New plug has lots of spark against frame .Poured a little  fuel down the head installed plug and nothing.when turning it over it keeps backfiring but wont go.I found that while cranking if you give it some throttle it makes like a metal on metal noise.Seems to be lots of compression there as well.Im stumped tks.in advance.

[Mech]

Hi, and welcome along.

Have you checked fuel's getting in from the carb.. is the plug getting wet if you use the choke ?

That metallic noise..  some bikes do make a lot of noise when a heavy load is on the starter. opening the throttle can increase the load on the starter. If you can post a video with the sound of it cranking I/we might be able to tell if it's a normal sound.

The cam timing check is easy.. if an engine has a worn timing chain or tensioner they are prone to jumping the chain on the sprocket if the engine kicks backwards as it comes to a stop.

[Shadowace]

OK thanks metch I will do that tomorrow. 

I also joined  the quad crazy site and gave to do so may post to get the manual download 

[Mech]

Yeah the manuals are a great help. It's a good site.

I'd go to partzilla and check what the bike's exact model suffix is, then use that to identify the best manual..

[Gwbarm]

A little concerned the spark plug electrode was bent was it bent alot or just out of gap.

[Mech]

I've questioned that on another site. Play in a rod bearing can bend electrodes, but they have to be pretty bad to do it.

The noise might be related, or might not.

[Shadowace]

I put a new plug in today turned it over a few times and the plug came out fine , not bent . It didn't seem to do it today.I ah e no idea what to do next the bike is not worth spending too much money on .Sell it as a parts bike maybe .

[Gwbarm]

This may be a little extreme, but maybe a ring broke or piece of piston broke off and worked its way up there and hit the plug to bend the electrode, i keep thinking something may be in there for the plug to hit to get bent, was the electrode shinny like it had been hitting something, that would explain the metallic noise.

Have you checked the compression, or taken the new plug out to see if it got bent also.

[Shadowace]

Yes new plug is fine and lots of compression. 

[Mech]

And did you try the choke(without any throttle. The choke doesn't work with throttle.), and did the plug come out wet ?

[Mech]

Are you sure it's compression ? Have you checked it with a gauge, or a finger in the plug hole ?  It might be the piston hitting a valve you are feeling.

It was going till it got turned off.

"New plug has lots of spark against frame .Poured a little  fuel down the head installed plug and nothing.when turning it over it keeps backfiring but wont go.".

 

[Shadowace]

Even though I never checked with a Guage I did put finger over the hole and it has a pullchord as well and it is as hard to pull over as always.Im going to Check the plug with choke tomorrow. As well I know I've started other small engines before by putting a little fuel down the cylinder putting plug in and cranking it  over.Im surprised that isn't working. 

[Mech]

If you can't keep your finger in the plug hole when you turn it over it should be enough compression.

Yeah well it's backfiring so it's getting spark. The spark timing might be out.

It was going till it got switched off..  so check the switch perhaps.. The key switches differ but they all send 12v into the cdi, and a signal into the cdi when the start button's being pushed, it retards the timing I thing to take the load off the starter. The noise when the throttle's opened might be the starter straining. You could check that signal is getting into the cdi. It's a bit tricky though because some send 12v through the cdi then to the start button and on to the start solenoid, and others have 12v to the start button, and it then branches to the cdi and the start solenoid when the start button's pushed.

That retard function though isn't used when pull starting.. so.. perhaps try a pull start... Or.. a tow start.

[Huapakechi]

One thing you should check is timing.  If the spark is not arriving at the right time, it will backfire.  I've seen sheared flywheel keys cause this, usually because the flywheel nut wasn't tight enough.

[Mech]

Yup Huapakechi is right, a broken key in the flywheel could do it, but if/when you get around to checking the cam timing it will eliminate or point to that. Check the cam timing first, it's easier and checks cam and ignition timing at the same time.

[Shadowace]

Thanks again guys I will do more research and see can I find videos on this .I'm very mechanically inclined but that is way out of my knowledge. 

[Huapakechi]

My suggestion is to get the book, but be careful.  I once told a customer I could fix about anything with the manuals.  He gave me one printed in Japanese.

[Mech]

Yup, go to partzilla and find what your bike's model suffix is, then find a service manual.. The suffix will be either AM, AMC, FAM or FAMC

[Shadowace]

Thanks again guys , I'll post the outcome .