PTO Shaft run-out

[Jay4200]

I was running my 3pt snow blower the other day to see if everything looked alright before the season starts. I've never used one before, and bought this unit used this past summer.

Everything spun up fine, with no noticeable bad noises or excessive vibrations, but I noticed that the PTO shaft appeared to have some run-out. That is, the shaft seemed to be moving up and down 1/8" or so in the middle - the ends ran smooth and stable from what I could tell. I thought that maybe it was just the shaft cover wobbling around - I figured I'd be able to feel a bent shaft while running, but I didn't dare grab the shaft for obvious reasons:

Hilarity of that warning sticker aside, is it possible that the shaft is slightly bent, or is it common for the plastic shield to exhibit some run out with the interior shaft straight? Is some run-out common with telescopic shafts and not a problem? The shaft telescopes smoothly and everything seems to run OK w/o any excessive vibration - I have not, however, run the blower with a load yet.

thanks - JayC

 

[LD1]

It could be a combination of both the cover and the shaft.

But there will be some runout due to the two halves sliding over eachother. There has to be a little play or otherwise you would have a difficult time extending the pto shaft to hook it up and collapsing it to remove.

If you dont notice any vibrations and the u-joints are tight, I wouldn't worry about it.

PTO shafts run at a slow rpm (540). You should see the slightly bent PTO shaft on my bushhog with worn and sloppy u-joints. Even though it looks bad, It hasn't broken yet and there is no vibration at all. Again, due to the relatively slow RPM that these things turn.

 

[jimgerken]

Jay, make sure that when the shaft is connected, and at any height raising or lowering the snowblower, the shaft maintains a minimum of 6 inches of overlap. Less overlap would show itself as runout, until it blows apart under heavier load.

 

[ihuntbear]

you said it was a used unit.Maybe the previous owner had to cut the shaft for his tractor.Maybe now its to short for yours.You need to check for the proper length.One of our sponsors has vidieos on this.good luck

 

[Jay4200]

Thanks for the hint about length/overlap. I'll check it, but I think it is OK. I don't know exactly how far it telescopes, but based on this pic (close to running position), it doesn't look like it is pulled out very far - 5-6" maybe. I don't think it moves much during 3pt travel either.

JayC

 

[jimgerken]

Judging by the shield, I'd agree. Unless they didn't cut the shield???

 

[beenthere]

It is easy to check the length.
Just disconnect it and pull it apart. Measure the length completely shoved together, and the length when it just comes apart. Compare that length to its connected/running length and you will then know exactly how much overlap you have.

Some movement in the plastic shield is normal or nothing to worry about.
But I would double check and know how much overlap I have so I wouldn't have to be concerned.