Idler Pulley

[Ricks]

Mike, what is the diameter of the late pulley?

Rick

[Mike Sal]

Wayne said they are 3" diameter.  The one I have now is 2.75".  He said the aluminum ones (earlier ones) are smaller.
Mike Sal

[Ricks]

The aluminum ones are 2".  Why not just switch to the earlier style, or do you want to keep it as close to the original as possible for the year?

Rick

[Ricks]

Mike, I just did a quick search.  Check this out:  http://www.ebay.com/itm/MURRAY-91179-421409-OREGON-78-027-FLAT-IDLER-PULLEY-/150553369621#vi-content

the ad says it's steel, 1/2" bore and 3" OD.

Rick

[Mike Sal]

I'm going with the steel pulley just to keep the stock appearance, although I agree that the aluminum ones look better.  That murray pulley you referenced is exactly what I'm going to be picking up.  We do have a farm supply store here local that carries mower parts, so I should be able to get it here.

Wayne told me that he drills out the rivets & rebuild these pulleys to get the bushings & spacers he needs, then puts them back together with small screws.
Mike Sal.

[admin]

Post a picture and Part # of whatever winds up working, for future reference.

Rick

[Ricks]

Mike,  did you ever get the idler pulley?  If so, please post a picture.

Rick

[Mike Sal]

Sure.....as soon as I find it.  I came home with it yesterday & had it in the same bag with some lawnmower parts (hit a stump & bent a blade, so thought I'd change the oil & other things will replacing it).  I thought to myself, now don't scatter all this stuff out & loose it.....well, I kept track of everything but that darned pulley.....it's still in the bag it came in.....I'll surely find it tonight, I hope.  I may have layed it down by the hydraulic press.....it came with a bushing to size the hole down to 3/8", but the bearing itself has a 1/2" hole, which is what I want.  I'll press the bushing out & be ready to go.  I'll make a new shoulder bolt to mount it to the bracket, based on the picture of one in the parts catalog. 
Mike Sal

[Mike Sal]

Here's a few pic's of the new pulley (notice how small the bearing is in the old one...which was not a Simplex part).  The bearing had a larger diameter than I expected (nearly 11/16....not the 1/2 that I wanted).  This was a mower deck pulley for a kubota lawn tractor.  I drilled out the rivets so I can replace the stock bearing with a new one with a 1/2" diameter hole which I'll pick up tomorrow.  I'll then use some small screws & nuts to bolt the 2 halves back together I'll then make a new mounting bolt (I have some Hex stock laying around).  The parts catalog shows the bolt going in from the bracket side & using a nut behind the pulley.  My problem is the nut that is welded to the bracket (which does look like the catalog drawing) has 1/2" threads in it.  This means the bolt has to go in thru the back side of the pulley first, and I may not use a nut.  When I talked to Wayne, he told me he does the same thing when somebody orders an Idler.
Mike Sal

[Mike Sal]

Found out that a 1/2" I.D. bearing with the same O.D. as the 6203 bearing isn't easy to come by here in kornfield kounty, so, since I was going to have to make a new shoulder bolt anyway, I just re-used the 6203 (I didn't need to drill out those rivets....darn it) & made the shoulder bolt to fit.
Mike Sal 

[admin]

Nice work Mike!  It's nice having the right tool for the job.

Rick

[pd]

This is the same way the model T guys figure their speed.  They only rev to about 800 or so rpm.

I read somewhere what the ratio's were between "low" gear & "hi" gear on a simplex, but can't find it now.  I thought they even mentioned what rpm the engine topped out at, but again, can't remember where I read it.

I think 1 to 1 may be too tall, but don't know what torque your engine is rated at.
Mike Sal

Maybe here :

http://en.wikipedia.org/wiki/Simplex_Manufacturing_Corporation

[Ricks]

While looking around at Tractor Supply, I found a pulley that is very similar to the stock late simplex pulley.  It is made by Phoenix and is 3 3/16 OD x 7/8" flat width. which is exactly the same as the one I took off my Sportsman and off another frame that I had.  The only difference is the bearing is 5/8" bore, whereas the simplex is 1/2".  I was going to turn a spacer on my lathe, but right next to it was an adapter bushing, and for the $1.99 they wanted for it, I just bought it.

Stock simplex pulley in black, the new one in gold cadmium plating.

[pd]

Good info , Rick .

I didn't think TSC carried Simplex parts .

Pete .