1250 Bad shaking when front PTO engaged

[olds45512]

Originally Posted by DeltaCub

The muffler box pretty much hides the PTO clutch. Remove the side panels to observe the PTO clutch.

That's stupid, I guess I can add that to my list of reasons not to own a QL.

[twoton]

You check them mule drive pulleys?

[DeltaCub]

Originally Posted by olds45512

That's stupid, I guess I can add that to my list of reasons not to own a QL.

Tim, quit whining about Quietlines! They are great tractors and will run on a hillside without throwing a rod...usually! You need to try out a few and realize they are not the "Edsels" of the Cub Cadets

[mortten]

Tight in there.

[twisties]

Yes, checked the mule drive pulleys while I had the drive belt off.

I mentioned at the end of my initial post, this has been converted to solid mounts and a beefed up cradle.

It's not a light vibration by any means, this is a hood shaking I'm gonna tear myself apart shaking. And most of the time as soon as I disengage the PTO and drop it to idle it completely goes away.

[DeltaCub]

Originally Posted by twisties

Yes, checked the mule drive pulleys while I had the drive belt off.

I mentioned at the end of my initial post, this has been converted to solid mounts and a beefed up cradle.

It's not a light vibration by any means, this is a hood shaking I'm gonna tear myself apart shaking. And most of the time as soon as I disengage the PTO and drop it to idle it completely goes away.

Have you taken off the deck and removed the belt cover to inspect the belt, pulleys and spindles?

[Tom Dowling]

Smart move would be to drop deck and check/balance those blades, unbalanced blades can ruin bearings real quick. Somewhere in that driveline you may have a bad bearing but it sounds more like a broken or unbalanced blade.

[twisties]

Other than freewheeling the deck while I had the tractor up on ramps I have not done a further inspection. What's got me stumped is that it has worked just fine a few times but certainly not with any consistency.

As I mentioned, this was a project coming to me. Two owners ago it had some cosmetic work done, wrong color yellow, I know.

I know the deck is not from this model either, perhaps these pics would help ID it?

[DeltaCub]

Yes you have a 48" deck with a 44-50 style mule and hanger. The angle of the brackets for the front pulleys on the mule have a different angle than what that old style 48" deck uses. Double check the pulley and belt alignment. Also check the pulleys on the deck and spindles to verify they are running true.

As others has said...check the blades for damage!

[J-Mech]

Originally Posted by twisties

The only problem that I'm having is that about 9/10 times when I engage the PTO for the mowing deck, the tractor will start shaking/vibrating so bad it will almost stall out. If I immediately disengage the PTO it will continue to shake until I drop the motor speed to idle and then it smooths out.

..........................

I should probably mention that the last owner converted this to a solid mount engine with a beefed up cradle, IIRC he either got the idea here or got parts from someone here but I may be wrong on that.

Given what I highlighted, and the fact you say it has been converted to solid mounts, I think that the engine is loose on the cradle. If the shaking continues after you shut off the PTO, and continues until you slow the engine, I am betting your engine is loose.

So, the best asked question here would be, have you watched this problem with the hood open or the side panels off? That would be the first, next best step. A broken, unbalanced blade, or a bad bearing..... or really ANYTHING deck related would not continue to happen, and keep happening until you slow the engine, and definitely wouldn't shake bad enough to stall the motor. Pull the side panels, and maybe even the hood and watch what's going on. Set a weight on the seat (if it still has a safety switch) STAND AWAY FROM THE DECK and engage it while standing next to it. Lower the deck before hand and make sure you don't get near it. Can't stress safety enough here. Check it out, look it over.... you have got to be able to see a problem that big.

Originally Posted by twisties

Also has a new flex coupler on the motor side of the drive shaft and the transmission side joint is a U-joint.

Just as a note, the u-joint on the rear shouldn't be an issue..... but it isn't OEM. Might pull the tunnel cover and while it is NOT running, check to see that the u-joint is tight. DO NOT run it while sitting in the seat with the tunnel cover off. Just not safe. Key body parts are just too close to bad things if there is a problem when your sitting in the seat.
But, with solid mounts, the u-joint should work. As much flex as the the system was designed for, that u-joint may have worked loose. Don't know how the attached it to each shaft....

Originally Posted by Tom Dowling

Smart move would be to drop deck and check/balance those blades, unbalanced blades can ruin bearings real quick.

I have never in my life balanced blades. NEVER. I have mowed acres and acres and acres and never had a bearing failure. Not even for them being worn out. Not yet anyway. While balancing the blades makes sense, I can't see that they could ever be so far out of balance that it would cause an issue, unless they have been broken and a large piece is missing. Besides, the tip speed on these old machines are so slow, I don't think you would ever notice the difference.