John, Maybe Ted or John Erb could tell him more about the setup? I have no clue on the vs units.  

Frank/Rebop

Bristol, In ( by Elkhart) 

Bill:

Your plan sounds like a good one.  And Paul, I had one of those combines, and my present Gleaner also has variable speed pullies.  But my variable speed belt drive experience comes from several years of maintenance supervision in an industrial plant.

John - "The Hoosier Hurricane"

John, thanks for your vast knowledge on this subject and expeirence racing these units. So if i had a belt too long, it would not place enough tension on blower pulley, then one too short would overload the bearings and pulleys, then to be in the ballpark would i be correct with a belt that compressed the tensioner spring about 3/4 of its travel? Just need a starting point, thanks again. regards bill.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

John.......Your explanation makes sense to anyone that's ever owned a John Deere combine from the days before hydrostats.

 

Paul,

Boonville,MO

Dan and Bill:

Just a bit of added information.  When the blower is told it needs to put out more boost, it reduces the pressure against the piston that actuates the variable speed pulley.  The belt then tries to wedge itself deeper in the pulley, thereby pushing the piston out of the way so the blower will spin faster.  When boost reaches the preset value, the piston again closes the pulley and the belt has no choice but to ride higher in the groove by compressing the tension spring.  Hope this makes sense.

John - "The Hoosier Hurricane"

Thanks john, Dan and I both had same question re belt tension, you have made it clearer, guess i,ll go and try some belts. Thanks for the information. Regards bill.  

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

John, what you say makes sense.

Having just a little "working" knowledge of these things can definitely lead to false conclusions. So, I assume that the blower pulley itself has enough tension/pressure on its actuation (closing and opening, going from large diameter to small diameter) from the drive inside the housing, that the tension on the spring pack really plays no role in its movement, etc.

Therefore, I would also assume from what you are telling me that I need to get a belt that will fit the unit as close as I can get the spring pack to compress...upon initial installation (allowing for the minimum diameter of the blower pulley to have good friction on it because the spring pack is still holding it snugly around all of the pulleys in question)...now that's a mouthful!!

I will check out Chuck's belt first and go from there.

Daniel Jessup

Lancaster, California

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com

Dan:

I would think that with the blower pulley at it's maximum diameter, that is opened fully, the idler should be compressed all the way.  The spring and belt do not determine the opeining of the variable pulley, the piston inside the blower does.  The spring merely maintains tension on the belt so it won't slip, regardless of pulley position.

John - "The Hoosier Hurricane"

Try John Erb. He has a lot of parts and knowledge about the McCullouch's.                                             John Erb                                                                                                                                       4019 ponderosa dr.
Carson City, NV 89701

johnerb@sbcglobal.net

Chuck in NH

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

chuck - thanks for the numbers - I will check these out tomorrow at one of our mom and pop shops in town that still carry a LARGE selection of Gates belts. I assume they have a cross-reference. Many times these folks are still using the old reference books and so on. Have a good trip this weekend.

Bill - I will keep you posted. I guess we think along the same lines. And of course, you and Chuck tend to be the fellas that answer my questions about the VS57 the most. Guess not too many are running that particular blower. I know there are a few well known fellas that have the VR57. John Harding, back when I bought an isky blower cam from him, gave me the names/contact info of a few fellas that have good knowledge of these blowers. It is probably about time I looked them up. Unfortunately my project has been on hold because of my new garage, all of the moving and setting up, etc.

Maybe I should have started posting in the this and that section, but I thought that maybe somebody would have a good belt for sale.

Daniel Jessup

Lancaster, California

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com