2 Stage Blower Progress Update

Last winter a 2-stage blower, cab, and 520H followed me home

Upon inspection, most of the bearings were toast, there was a lot of rust, the auger shaft gear box had major problems, the impeller had been chucking rocks, and a few parts were MIA.

The auger shaft gear box was badly worn and the impeller shaft was riding on the case. I found a used case and some new bearings.

The impeller was badly bent and cracked. Some torch, hammer, and welding had that back close to original, but when I put it back in the housing, I had as much as 5/8" clearance. I had planned to put in the rubber belting modification, but once I had the new paddle plates in position I had about 1/8" clearance and decided to call that close enough.

I decided to replace the bronze auger shaft bearings with cam lock ball bearing, that required a 1/4" spacer to move the bearing inboard to clear the end of the shaft.

The original design for the chain tensioner used a wood or plastic rub block. My rub block was shot so I decided to replace it with a idler sprocket.

After a summer of wire brushing, sanding, Scotch Briting, and painting, I was finally ready for some reassembly. Here is where I am now. I still have the belt guards to put on.

I think I have just guaranteed little or no snow for the winter.

Kurt

My little herd,

A single stage blower will be going on my 95 520H for the winter.

Kurt

Super nice job Kurt! If I didn't have a gravel drive, that's what I would have.

A gravel drive didn't bother the previous owner. I think the average diameter of the stones was 2 inches. You could see the damage on the impeller. I wonder how his windows held up?

Kurt

Kurt, superior job and improving on the old worn out design of some parts. Nice,,,,,,,,,thumbs up.

Glenn

1st class job Kurt, looks awesome! :goodjob


Would you mind sharing where you got your cool modification parts?

Nice job...I like it because we will officially have no snow....but if we do you will be prepared....

Geno wrote: Would you mind sharing where you got your cool modification parts?

Two Stage Snow Blower Parts
From my notes for my Two stage blower. Maybe these will help someone in the future

Model 79361
Serial 4900582

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Belt
Toro 116332 - 5/8" X 64.5"

Pix makes a 5/8" X 65" belt that fits well - TSC has them

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Chain is #40 1/2" Chain. TSC has it.

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Impeller Shaft is 7/8" and uses a Cam Lock Bearing no. SA205-14

Auger Shaft is 1"
For my bearing modification I used Cam Lock Bearings no. SA205-16. 1" ID. Spherical OD from US Bearing and Belt - TSC has them as 1195167

Flanges are T52MSTRZP-1 TSC has them as 1198717. I got them from Ebay as 52MSTR. They are 52 mm ID flanges for 7/8 and 1" bearings.
The ones I ordered were Fafnir 52MSTR ZR
I had to fabricate a 1/4" spacer to move the auger shaft bearing inboard. Without the spacer, the bearing came out past the end of the shaft.

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Auger Shaft Gear Box part nos. from Toro

Impeller Shaft Gear Box Seal 7/8" dia # 237-87
Auger Shaft Gear Box Seal 1" dia 7-0045
Thrust Washer - 1" 252-71
Impeller Shaft Woodruff key - Hi pro - 3257-23

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My two stage blower used the same auger shaft gear box as a 521 two stage walk behind (Toro number 38035 and 38052). It maybe the same as
the 421, they use the same gears.

Gear box case numbers were 37-6940 and 37-6930

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Auger shaft gear box gasket is 51-0460, also fits 3521, 521, 522, 524, 622, 624, 724, and 824.
The case and gears may be the same in all of these.

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Impeller Shaft sprocket is 33 tooth for No. 40 chain, 7/8" bore.
I purchased a sprocket and hub from McMaster Carr - Needed to weld the sprocket to the hub

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I use an ideler sprocket to replace the block (wood or plastic) that was used to tension the chain.
I used a no. 40 ideler sprocket I got from TSC. I had to add an extenion to tensioner bracket to move the sprocket downward about 3 inches.
I need this space to give me some additional clearance so I could tension the chain.

Wow, that is very detailed, thanks Kurt!

Great job Kurt and thanks for all the info.