Motor No Start

[nomad]

2000 Warrior
Turns over and hits, but won't start. Occasionally will backfire.
- replaced ignition coil
- replaced pickup coil
- disassembled/cleaned carb
- checked time (was 180 out)
- fixed timing
- checked spark

Now that timing is right I'm getting fuel/air blowback into air intake. Any thoughts on how I should proceed? Thanks!!

 

[Mathius]

You could have a bent valve from your timing being so far out.

 

[88WarriorBoy]

flywheel key is sheard more han likely lol a 10$ part can cause so much money loss in new parts because a guy on the forum just went trough this

 

[Mathius]

Yah it could be the key..

 

[YAMAHAULER]

take the timing inspection plug out and turn over is the flywheel and magneto spinning?
do you have compression?

 

[nomad]

Mathius - That's what I was thinking as well.

As far as I can tell the flywheel and magneto are spinning. Has compression, but I don't have a tester to get an accurate reading.

 

[nomad]

How would I go about checking to see if the valves are bent?

 

[Gen1Pat]

Compression test, or better, a cylinder leak down test. Other then that, you'd have to pull the head and visually inspect.

 

[nomad]

Ok thanks!

 

[nomad]

Any idea where I can get a decent deal on a leak down tester?

 

[lbjamm]

Definitely do a leakdown test. Harbor freight has a tester for $40.

 

[smith89]

:heck:it could be the intake manifold

 

[lbjamm]

Now that timing is right I'm getting fuel/air blowback into air intake. Any thoughts on how I should proceed? Thanks!![/QUOTE]

Intake valve not seating. Could be valve clearance.

 

[nomad]

Did a compression test. 100psi. Isn't 121psi what it's supposed to be getting? It also didn't jump up to 100 fast. Took a while in jumps of 10-20 psi. Thoughts?

 

[lbjamm]

Did you check valve clearance? You can put a teaspoon of oil in the spark plug hole and retest your compression. If it gets better. you need rings. If not, it's your valves not seating (maybe bad seats).

 

[nomad]

I didn't check clearance yet, does it require any special tools? I'll try that with the oil too. Thanks!

 

[lbjamm]

No special tools other than a feeler gauge. I can't remember the specs. Maybe someone else will chime in. Just do a search. Somebody posted the specs the other day. If the valves are hanging open it won't run. At least not good. Good luck.

 

[nomad]

Thanks! I'll try and check it this afternoon.

 

[nomad]

Just removed the intake and exhaust tappets to do the valve clearance check. Noticed the exhaust rocker has some play while the intake is very solid with no play. Is there any significance to that?

 

[nomad]

With crank web on T both rockers have a little play. I'm guessing this is normal. Sorry if all of this is really elementary. This is my first atv motor lol