98 timberwolf rolls over has good fire, fuel, compression but won't start only loud backfire

[Bdubb0227]

Hey guys, I'm new on here but I have a hell of a problem.  I traded for a 98 timberwolf 2x4 and it ran good but smoked.  So I decided to get piston and rings with new jug a and put everything together did the timing by the marks on the fly wheel and the cam gear and now all its is rolling over in the back fires extremely loud someone please help

[Mech]

Sounds like bad ignition timing, or an air leak into the inlet manifold.

 

[Gwbarm]

Agreed, I would double check the timing marks make sure nothing moved.

[Mech]

Oh. Yeah.. the cam timing..  haha..

Or a tight valve or an air leak into the inlet,

[Mech]

Then, if you're real sure all your work is right, is the fuel fresh, are you really sure the spark plug is firing under the new improved compression ?

[Bdubb0227]

7 minutes ago, Mech said:

Then, if you're real sure all your work is right, is the fuel fresh, are you really sure the spark plug is firing under the new improved compression ?

 I've checked the timing numerous times make sure it was on the compression stroke rings are on correctly even with  carburetor off and starting fluid it won't start just rolls over and over and back finew spark plug fire's great healthier air won't start

[Gwbarm]

Oh by the way, glad to have you, welcome to the forum, lots of good information shared.

[Bdubb0227]

I went out checked to make sure timing was correct on the compression stroke,  it is all correct.  Great fire, new gas/starting fluid,  compression.  Still it won't start,  so I began changing timing by about 10 degrees at a time. The last time before my wife said I had to eat supper it tried to start  But was shooting blue flame out the carburetor.

[Mech]

Could it have a sheared key on the crank ?

Are you sure your spark plug is good ?

[Bdubb0227]

Has new plug, I don't know how it would have sheared the key. Didn't wreck, or hit anything. 

[kp3004x4]

If you check your timing and it's tdc you could have sheared a key sometimes keys just bend and not shear and throws everything off just a bit. Just A last effort pull flywheel and see if key is good.  Hope the best.

[Mech]

Might pay to confirm the timing mark on the crank is in fact at top dead center.. If you take note of where the crank is when the piston is some certain distance down, both before and after TDC, then halve the distance on the rotor, it gives a pretty accurate check.

To make it accurate you have to be moving the piston up just before taking the measurement.. 

Edited April 2, 2023 by Mech

[kp3004x4]

I would agree with mech I use a plastic drinking straw to check tdc when I can't get to flywheel sometimes,just pull plug rotate engine until straw comes up then goes down tweak it until u know it's tdc then look at marks if off then you have a bad key.  Hope that helps you.

[Gwbarm]

I just been reading all the post and thinking about it , I think you are 180 degrees off, even if you were off by a couple of teeth it should still try to start, when you reinstalled the cam were both lobes pointing down.

[Bdubb0227]

Yes both were down. If I am 180 off would both valves be closed and it be TDC? And how do I make sure it's the way it should be. 

[Gwbarm]

If both were down your good, im just trying to figure it out, when you installed the cam gear the arrow was at 12:00, both valves closed on the compression stroke, no reason it shouldn't run, did you check the compression after installing new rings.

[WillrogersII]

Yep sound like a timing issue to me as well. 

[Mech]

If the cam timing was off by 180 degrees then turning the crank 360 degrees will bring it to the right place again.

If the rotor key was broken though then the ignition and the cam timing could be right off..

 

[Bdubb0227]

Well guys thank u all very much.  All the input was valuable,  but as I was removing the flywheel I was tired of the junk thing and I beat it with a sledge hammer until the entire crank case was in little pieces.  

[Gwbarm]

Sorry to hear that, we would have figured it out, I understand, been there many times, walk away, forget about it for a few days, come back with a clear mind.