Hydraulic snowthrower chute re-do

[Jim Timber]

The original chute rotator was seized when I bought my New Idea 7' snowthrower. Normally, I'd just rework the bad bits, but in this case the mechanism had been designed by a disciple of Rube Goldberg and I wasn't about to waste any time "fixing" it. Fortunately, they did one thing "simply", and with 2 bolts and a cut cable clamp, the works were discarded.



The original design used cable wrapped around a pulley on one end and the chute base on the other. I decided the more elegant solution would be a gear around the chute base, as most walk-behind units use, but I didn't want it worm driven (slow), and I didn't think I'd find any cheap traditional gears this size. So a chain sprocket became the obvious choice as they're cheap, readily available, and would hold up to the task indefinitely with little future maintenance.

Next step was to free the chute base from the chute. Thankfully, someone "farmer welded" the four points attaching the two components, and breaking them free was relatively painless.

Those welds... Ooof!



With the base free, I cut off the cable clamp bracket and cleaned up the OD of the chute.

I knew from previous measurements that my gear needed a 12.625" ID hole to fit around the chute base. So I fitted a piece of 2" OD scrap to it's mounting hole, and clamped it in my Super Spacer on my mill.



Turns out, I could've stood to have cut the hole a few thou larger, as it took a concerted effort getting the gear around the base, but I did it without heat and no blood loss. :laughing:

After considerable pounding, I managed to get the sprocket down where I wanted it, and then welded it up.



Since I'll be rebuilding the chute when weather improves, I only bolted it back on the base.

I didn't take any picks of the hydraulic motor mounting bracket. It's just heavy angle iron with the appropriate bolt pattern and a 1.75 I.D. center hole to allow the motor to sit flush, then some 1x1 galvanized tubing added.

First mockup of hydraulic motor:



Then it was just a matter of measuring where the chute sprocket was relative to the top of the auger housing, and marking & drilling the holes.

Bolted everything up and added the hoses - she's good to go!

 

[old and tired]

Very nice...

 

[Jim Timber]

Thanks!

I still need to rig up some hose clamps, but I'm pretty happy with how it turned out.

 

[senecak19]

Do you happen to have a before photo? I'm very curious to see what the Rube Goldberg setup looked like. Your simple (no pun intended) setup is awesome! I'd like to pick up one of these at some point and would love to rebuild one like you!

 

[Jim Timber]

The first picture is the OEM contraption removed.

The cylinder push/pulled the lever, which swung a half-round "rack" gear, which in turn rotated a pinion gear, whose shaft turned a pulley, which wound/unwound a cable, which was supposed to be wrapped around the chute base where my driven sprocket now lives.

Whoever had it before me didn't have the cables rigged correctly, which might explain why the pivot and pinion bushings were locked up solid.

This is the only pic I have of it on the snowthrower.



What baffles me, is that with all the welding and specialty parts, plus a reasonably large cylinder - it's cheaper to buy a hydraulic motor to begin with.

Granted, mine was dirt cheap as NOS off ebay, but Surplus Center carries motors for $150 new. So it isn't like they couldn't choose an off-the-shelf part to use and simplify the whole works.

 

[Jim Timber]

I pulled up some others that are for sale to show the original configuration.

 

[senecak19]

This is an ingenious method. I haven’t worked as a machinist in 24 years. Crap has it been that long???? Anyways, I miss having those machines at my disposal. When I find one for the right price, I’ll call you to machine a sprocket for me

 

[Jim Timber]

Thanks!

I'd be lost without my shop. :laughing: I don't even do napkin drawings for 3/4 the stuff I make.

Since we've got a storm coming, I moved the tractor and took some pics of the motor mounted up.

 

[robstaples]

Jim, how did you get the circle on your mill. I did something similar but used plasma to cut the sprocket.. Did not turn out as well. I may redo it.
Thanks, rob

 

[Jim Timber]

I tacked a piece of 2" scrap into the bore of the sprocket, then clamped that in my super spacer's chuck.

 

[senecak19]

If I try hard I can probably get access to a Bridgeport but not that chuck! Now to find me a nice snowblower like yours.

 

[pmsmechanic]

I tacked a piece of 2" scrap into the bore of the sprocket, then clamped that in my super spacer's chuck.

View attachment 683151

You don't need a mill to do this job. I will say it's nice to have one though.

All you need to do is figure out how to rig up a circle cutting attachment and then use either a cutting torch or a plasma cutter to cut the sprocket to size. The accuracy would be close enough for this application.

 

[Jim Timber]

Plasma and torch both leave dross that's gotta go before welding, but if it's what ya got - then yes, they'll get the job done. If you're using one of those methods, it'd make sense to cut 3 or four pieces of "pie" out of the sprocket, while leaving yourself some "legs" towards the center. That way you have less surface to grind clean, and fitting it up tight for the welds should be a snap.

If you have access to a lathe, you could cut it on that as well.

I love my super spacer! They're crazy expensive now, but I got mine 10yrs ago for $400 and it's been worth every penny.

 

[pmsmechanic]

I just wanted to point out that you don't need an expensive set up to do this for someone thinking about adding this to their snow blower. I have rebuilt several rollers just using a cutting torch. I haven't measured the run out after I was done but it was good enough that you couldn't see any runout with the eye.

 

[Jim Timber]

Runout on this application is a non-factor. You just need it round enough to not throw the chain, and even that can be compensated to an extent with a spring loaded idler arm.

 

[Dougeye]

A simple and elegant solution, expertly done. Good job. I'm wondering if you've thought about putting some stops on the rotation, maybe 90 degrees apart, to avoid the possibility of the operator getting a snootful of snow.

 

[Jim Timber]

Thanks!

:laughing: Stops are for sissies.

Actually, with the size of the motor, I'd need to put pressure reliefs on both lines or the drive would likely rip itself off the chassis with hard stops.

So this one will require the operator (me) to not over-rotate while in motion.

 

[PILOON]

I modified my blower chute in a similar fashion but used an ATV winch for power'.
I mounted the winch vertically similar as U did and gave the winch 5/6 turns in either direction with the middle pinned to the drum.
I next wrapped one turn around the blower chute and anchored the ends.
With the ATV winch rated at 2000 lbs there is plenty of torque for the chore and electric is much easier to 'plumb' than hydraulics, besides with hydraulics you also need a control valve, hoses and fittings and that providing you have an available circuit.

My DIY rotator cost but a winch @ $+/- $75. and a DPDT switch @ $maybe $5.00.
I must be on my 8-9 year without any problems.
I did add an Anderson connector for easy seasonal connection.

I do admire that the poster did do a nice job of modifying and posting his fix.
I enjoy reading all the alternate fixes for various problems.

 

[Jim Timber]

I've got 3 empty SCV's out back when the snowthrower's hooked up.

I have a 2-spool valve dedicated to top & tilt, then I have a 2-spool I use for my stump grinder.

It'd actually be more work hooking up an electric device.

Not the best pic, since it was taken at night:


Had to make some 90ｰ blocks and custom banjo bolts to give the QD's room to work.

 

[Jim Timber]

Used the chute actuator today and it worked flawlessly. It's so nice not having to guess where to aim it, only to find out you're wrong as you get showered in snow. :laughing: