Too Much Vibration. Model 7268

[Bill52]

Hi guys. Thank for I need your help again.
I bought a model 7268 used 2 weeks ago to mow my acre of hills. It ram fine but vibrated a lot. I replaced the blade with a new one and that may have helped a little but not much. All the vanes are still in place on the flywheel and all the magnets. I just finished replacing the crankshaft because I thought the other one was bent but that didn't eliminate the problem. The vibration is not too bad when the motor is not running hard but it surges and vibrates a lot when it is surging. Any suggestions as to what the problem could be? Preciate it.

 

[mechanic mark]

Post mower make & model & serial number as well as engine make & all numbers from engine.

 

[Bill52]

Mark, it is a model 7268, serial 9790726. Runs strong and the deck is in near perfect shape but for some reason it vibrates a lot when the engine is running fairly fast.

 

[bertsmobile1]

usually this will be because the blade is not on properly or is out of balance.

 

[Bill52]

usually this will be because the blade is not on properly or is out of balance.

Brand new blade and I checked the balance before I put it on.

 

[littlefan]

on the muffler look at the tringle plate that the three bolts go through it should have about 010 gap all the way around it. lb had a gauge tool to set this but it can be done with a shim. When not even they will vibrate like a blade way out of balance

 

[FuzzyDriver]

To equalize the distance between the shaft and the muffler bracket I use the sheet metal from a Coke can. Roll it into a cylinder that fits inside the muffler bracket, let it expand, and then slide it onto the crankshaft. Remove it after tightening the bolts to spec. And, ABOVE ALL, wear gloves! Those cans can really cut you!

 

[Bill52]

Thanks to both of you. I will try this today. I hope a Pepsi can works as well. I'll keep you posted.

 

[Bill52]

I did the pop can between the crankshaft and the triangle plate and that did not improve it. Any other ideas?

 

[tom3]

I wonder if the blade adapter might be out of whack in some way. those things aren't made real strong I think. I'd pull the spark plug, rig up a guide pointer and rotate the blade around and see that it runs the same depth up and down and the same distance (runout) from side to side.