F3 left pivot drive belt replacement
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=152707
Printed Date: 06 Nov 2025 at 5:32pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: F3 left pivot drive belt replacement
Posted By: wekracer
Subject: F3 left pivot drive belt replacement
Date Posted: 03 Aug 2018 at 11:25am
|
The pivot drive belt is in bad shape and I need to replace it. What’s the easiest way to remove the variable speed header drive belt. I tried prying the sheaves apart with no luck. Looks like I can remove the nut from the end of the counter shaft and take the outer sheave off. I can’t tell if the spring will fly appart though. Thanks
|
Replies:
Posted By: DrAllis
Date Posted: 03 Aug 2018 at 12:14pm
|
Operate the machine and header drive and speed the drive all the way fast. Shut down the machine. Disconnect the hydraulic hose and crack the swivel fitting loose on the center of the V/S pulleys. Spread apart the top sheaves and spray oil all over. Roll the old belt off and the new belt thru the very loose V/S belt.
|
Posted By: SteveM C/IL
Date Posted: 03 Aug 2018 at 10:25pm
|
The spring is encased in a can. Spring gets full spread before nut runs outta threads but Doc's suggestion is at least as good.
|
Posted By: wekracer
Date Posted: 04 Aug 2018 at 10:26am
Thanks for the advice. This is a new machine to me and the fitting for the sheave won’t take grease. I’m afraid it may be froze up.
Plus I have a series 3 head with the reel pump on the head. Don’t you have to switch some wires to make the variable speed head work
|
Posted By: SteveM C/IL
Date Posted: 04 Aug 2018 at 2:23pm
|
When you take nut and spring can off,the outer sheave slides off hub.My F2 was so snug a fit it was near impossible to grease it with tension on belt. I finally took a die grinder and cut a small spiral groove in part the outer slides on.It helped but still takes effort to grease it. That greasing is what lubes the cam in the spring can. It's needed. F2 is old school with no electric over hyd so can't help on the head issue.
|
Posted By: wekracer
Date Posted: 06 Aug 2018 at 5:45pm
|
Just as I thought. Both sheaves were stuck together. I was able to loosen the belt and slide it off the shaft. I now have my big 3 jaw puller on it. It seemed like the sheave was flexing so I didn’t want to pull on it too hard. I also read that there are o rings in there. I don’t guess it Will hurt to heat the outer sheave.
|
Posted By: SteveM C/IL
Date Posted: 06 Aug 2018 at 9:49pm
|
O-rings are common and probably need replaced anyway.I don't know how careful you have to be when applying heat.Probably be good idea to heat the whole sheave gently. It's cast iron (pretty sure not steel).I don't know if the center is heated more than the rest,if it could try busting. I once heated the big bin unloader pulley (hub only) on my A2 to get off shaft.Busted the outer diameter.The center grew and the outer did not and something had to give.It had spokes and wasn't solid. Just exercise caution. Worst case you can get another from the "yard". Report results.
|
|