Snowblower PTO rpm

[waybel]

Hi could someone tell me what an old B2551 front mount snowblower PTO rpm should be.it was on a F2000 Kubota.Guy who knew the previous owner said it had 2 speeds 1100 and 2500 and they ran the blower on the 1100RPM setting and the mowing deck on 2500 RPM setting

 

[torch]

I have a B2550 front mount blower, which may be similar. The owner's manual says "Operate the smowblower at maximum RPM". Further on it says "Use full RPM power when removing wet, sticky snow. Low RPM pwer will tend to plug the chute."

The mid-PTO on the tractor it came with is rated 2453 RPM.

 

[waybel]

here it is .Are those gears and chain( not attached) to reduce PTO speed .He said it was purchased new like this.

 

[torch]

Mine is different then, as it only has 2 gears. An 11 tooth and a 32 tooth, IIRC, so roughly a 3:1 speed reduction. Which would bring it down to the neighbourhood of the high speed setting on my rear PTO.

I wonder if all your gears are used at the same time, or if perhaps that unit was convertible between front mount and rear mount, with different chain routing for each?

 

[waybel]

good question!! The other 2 gears are just idlers.I am not even sure how the chain is routed.I bought the old blower to try and fit it on an F910 John Deere front mower I have.The John Deere has a 2000 Rpm PTO(only one setting).Guy on another site I tried to get help on says to forget the chain and sprockets and will sell me a gearbox $300.00 to mount directly on the main driven gear and then connect it directly to the PTO shaft.The original owner said he had problems with chain breaking frequently on this

 

[kubotasam]

Gears set up like that are used to reverse the direction of rotation. Count how many teeth are on the sprocket that is on the end of the pto shaft. Then count the teeth on the sprocket that drives the impeller. If they are the same then you have a 1 to 1 ratio and I believe you should run the lower speed.

 

[North Idaho Wolfman]

The fan should run at about 540 RPM, the gear reduction should be about 2 to 1, thus making the blower work for either 540 rear PTO or the 1130 front PTO depending on how you hook it up, either direct drive (PTO shaft connected to blower at 540 RPM) or threw a reduction gear / chain setup (with Mid PTO feed of about 1130 RPM.)

That unit looks to have a home made gear reduction, and revers rotation setup on it.
Might have been used on another tractor that had an odd rotation PTO shaft.

 

[waybel]

Found out more info.Guy who drove this for previous owner said it was used on Kubota F2000 and ran on 1100 PTO rpm.my john deere pto is 2000 rpm and turns counterclockwise and the main gear middle one in picture is CC also. PTO gear has 13 teeth and main gear for impeller has 18 teeth. not sure how could route the chain to get it to turn the main shaft counterclockwise except for just the 2 gears PTO and main.Tried routing different ways around idler gears(the other 2 in pic) and main turns clockwise.Chain that was broke but still attached looks long enough to go around one and possibly both idlers less a couple of links.Guy on another site was showing me some type of gearbox that I could bolt on bolts to the main gear with the other end connecting directly to the pto shaft.Guessing it reduces pto rpm through this gearbox?

 

[torch]

1100rpm * 13 / 18 = 795rpm at the impeller.

If you go around just the input gear and the impeller gear (and possibly around the top of the upper idler), the impeller would rotate the same direction as the driveshaft.

If, however, the chain was routed from the input gear around the left side of the left idler gear then around the right side of the impeller gear then around the top of the upper idler gear, the impeller would rotate the opposite direction of the driveshaft.

 

[waybel]

1100rpm * 13 / 18 = 795rpm at the impeller.

If you go around just the input gear and the impeller gear (and possibly around the top of the upper idler), the impeller would rotate the same direction as the driveshaft.

If, however, the chain was routed from the input gear around the left side of the left idler gear then around the right side of the impeller gear then around the top of the upper idler gear, the impeller would rotate the opposite direction of the driveshaft.

but the John Deere pto is 2000 rpm only one setting

 

[waybel]

but the John Deere pto is 2000 rpm only one setting

Anyone know what I need with the PTO of 2000 RPM coming from tractor??

 

[North Idaho Wolfman]

If your only output is 2000 RPM, You need to get a different gear box or change a sprocket to bring it down to around 540RPM

 

[waybel]

Well I finally got back to working on the snowblower.Bought a 12 tooth and a 32 tooth sprocket for the main.Decided to forget about the idlers because i have no idea why I need them.Hooked the chain up to the 2 sprockets.Turned it by hand and it appears that the fan shaft is bent a bit as it is snug in one spot and looser on the rest.Is there a chain guide/tensioner that I could hook up to take the slack out and if so where would I find such a thing?I haven't tried it yet but I assume this isn't good.Also worried about the chain falling off

 

[waybel]

Well after all was ready for a try to see what would happen the PTO for the John Deer was too short by about 4 inches.It was ok for the mower because it slides under the front of the tractor.Is there a way to attach an adapter of some sort to the 1 inch keyed shaft to make it longer?I also see they sell 36 inch length of keyed shaft .Could I replace the existing shaft and cut it to the proper length? How long of a shaft sticking out of the blower reduction plate is ok to use to attach PTO shaft ?I need about 6 inches longer to be safe but would prefer more