Converting front-mount Olathe leaf blower to rear 3pt

After just a quick look at the PDF, and assuming that the location of the set screw for the keyway is as depicted in the drawing, I would use the Reverse mounting - which should locate the set screw in a place that is easier to access, considering the size of the sheave.

This also locates the sheave further in on the shaft - which can only be a good thing I would think.

The above assumes that the set screw is able to fully contact the keyway in that location.

Thanks for the input rswyan. It turns out that the Standard way was the only way if I wanted to keep the small sheave at least a belt width away from the blower casing to facilitate belt replacement. The large sheave spokes and grooves are slightly further from the casing mounted this way, but the bore grip and all other measures are the same regardless. The fan shaft is about 1/2" shy of making it through the hub bore but seems like the big sheave is tight and straight. I did have an alignment problem between the sheave faces but a shim under one of the pillow blocks was an easy fix.

I am a bit concerned my cheapo torque wrench is not working properly. The 'SK-type' hub installation instructions say 15lbs max and to leave at least 1/8"-1/4" space between hub flange and sheave face. I'm down to the spacing minimum and the darn split washers started to splay out, but no clicks yet. Will replace washers and check those bolt torques again.

With the sheaves installed and faces in alignment, I used a couple of ratchet straps to pull the jack shaft perpendicular and put some tension on the belts before tightening the pillow blocks. At first I thought I might need to get longer belts but it worked out ok and I do have a little bit more slide adjustment if they decide to stretch some. Supposedly the 'BX' belts don't stretch as much as standard 'A' or 'B' v-belts so it'll be curious to see what happens there.

My lead for a used PTO shaft fizzled out so I headed to TSC and grabbed a short fertilizer spreader shaft off the shelf and, with the mgr's help, what the display said was the correct yoke end to swap out one 1-3/8" 6-spline end for a 1-1/4" round to fit the jack shaft. Of course, when I got it on the bench at home I realized it was not, grrr. Was for the better anywise, ordered what I needed from ArgiSupply for 1/2 the cost. Should be here in a few days... just in time, 1st snow flurries yesterday.

sent you a personal message yesterday, looking for mounting frames and input shaft for groundsmaster 62 to hook up a model 67 blower

@ mperatikos - replied via PM

Been too busy last few days to post a project update but PTO shaft arrived damaged so had to wait for a turn around. Got the new one cut it down and pretty much ready to go now, just looking for something I can turn into a safety shield. Maybe give it a try tomorrow finally.

:smiley_aafz: Houston, we have a problem.

Something has gone terribly wrong. Instead of a hurricane force gale to scare my leaves back into the woods, my new blower hardly breaks wind! All I get at 540rpm rear PTO speed barely makes my leaves shudder, and running at 960rpm rear PTO speed with the mid mower going just makes them jump a few feet out of the way. Clearly, it isn't spinning fast enough. Only thing I can think of is the 1850rpm reference was actually Toro rpm, not blower rpm?

Does anyone know if the Toro Turfmasters have an integral speed increaser box for the front mount attachments? Thanks.

Are you turning the fan the right direction. Usually when you move a rear attach to a front attach you need some type of reverser. Your blower may be different.
Bill

After looking at your pics closer I have a question. You needed to increase the the rpm's from 540 to 1850 correct. If this is correct you have the pullys switched. The big pully should be on thge 540 rpm shaft and the smaller one on the blower. You slowed it down insted of speeding it up
Bill

Thanks Bill,

Yes the fan is turning in the correct direction, that was a big reason I felt the blower could be converted without too much trouble. Does it really make a difference which shaft the pulleys are on? The fellow at the power transmission shop where I bought the sheaves didn't seem to think so and, if you refer to the exploded parts illustration I posted earlier, you can see the lower sheave is smaller than the fan sheave in the oem setup as well.

I can only figure the seller gave me incorrect fan rpm operating specs but I've searched online and cannot find reference to it yet. I'm going to post in the Toro forum and see if anyone can help.

NOT happy.

It makes all the difference. Turn the small pully one turn and see how far the big pully moves. Now turn the big pully one turn and see how may times the small pully rotates. This is how you get your speed multipication..
Bill

Hooked_on_HP said:

It makes all the difference. Turn the small pully one turn and see how far the big pully moves. Now turn the big pully one turn and see how may times the small pully rotates. This is how you get your speed multipication..
Bill

Click to expand...

This is absolutely correct. I just started reading this post today, and as I was following the progress, I said to myself "the pulleys are reversed, the blower is going to be slower than PTO rpm". As I read further, I see that Hooked on HP noticed the same thing.
Switch the pulleys and that blower will really spin!