Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Snowblower speed


steve-wis

Recommended Posts

Well, I finally got the Agco Allis 918H in working shape.  This free to me tractor has now cost me about $350 to get running, and I picked up a blower for it also.  It runs fine and the hydro is solid, nice tires and seat, all in all a decent tractor.  Anyway, I put a new set of chains on it today (pics in show and tell) and set it beside my Allis T816 which I have used for years for snow removal.  With them both running and blowers engaged, the Agco blower runs alot faster than the T816 does.  As far as I know they both have the right pulleys and belts on them.  Was the T816, which is the same as the Simplicity 6216, made to run slower?  I have read about bigger and smaller pulleys on the blower but I think they are both original.  Anyone have any info on this?

 


Steve

Link to comment
Share on other sites

I'm thinking they should be about the same speed since they are both RBTs of roughly the same vintage.

The OEM setup for the RBT "Sovereign" type tractors is a 7" diameter driven pulley on the snowblower.  It's very common to change them out to increase the speed.  I run a 6 1/2" pulley for my setup.  6" seems to be common as well.  As you go smaller, the long belt drive belt should also be a little shorter - 3/4" for a 6 1/2" pulley and 1 1/2" for a 6" pulley.  On the 7100 series tractors, the OEM belt adjustment definitely covers the 6 1/2" pulley and probably the 6" as well. 

Another issue is engine speed; in my experience, many of the tractors aren't governed at the "design" speed of 3600 rpm, but more like 3400 or 3500.  This also makes a difference.  

I'm don't know how the T816 is setup; all my experience is with large frame tractors. Years ago measured "belt wrap" lengths for various pulleys and did some calculations (belt wrap is a more accurate calculation than just pulley diameter since it takes into account how exactly where the belt rides in the pulley V grove).  Based on OEM pulley, I found that the FDT pulley setup turns the blower 0.866 rpm per engine rpm and the 7100 series mid PTO setup turns the blower 0.752 rpm per engine rpm (13% slower).  I've never had a mechanical front PTO (standard for 7000 series) to measure, but for a front electric PTO (Allis 300/400 & Allis build Homelite tractors), it turns the blower 0..786 rpm per engine rpm (9% slower).

Hopefully this helps you some.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...