Nicholas Fluhart

March 30, 2013

Ditch Witch R40 Drive Chain

Filed under: Project: Ditch Witch,Trucks & Equipment — Nicholas Fluhart @ 6:48 pm

After using the Ditch Witch a few times, it became evident that it would be much easier and quicker to get around on it if the main drive chain was fixed. The 40 feet per minute, or whatever it is that the hydraulic drive produces, just didn’t cut it. So, we pulled it up in my shop and Philip began removing the damaged sprocket from the transfer case. The large sprocket coming from the transmission was fine, so he just needed to remove the small one.

Ditch Witch in the Shop

In order to do this, the brake rotor must be removed from the rear drive shaft and the transfer case has to be loosened and moved forward slightly to allow enough clearance for the rotor to drop out. The sprocket slides on the transfer case shaft on a key way and is held in place with a set screw. Upon closer inspection, it became evident that someone had tack welded the sprocket on the shaft. So Philip had to grind the weld off, which was not easy in such a tight space, then the sprocket slid off. In the next photo you see the shaft where the sprocket was removed and below the shaft, you see the loose bolts where the brake rotor was removed.

Removed from Shaft

And here’s a shot of the old sprocket. Definitely time to replace…

Sprocket Removed

Philip took the old sprocket to the bearing supply house to find a replacement. We also did some measuring to determine roughly how long of a chain we needed. He was able to order the parts easily enough and a couple days later we were going back together with it. First the new sprocket was installed in reverse order of the disassembly. Next, we needed to cut the chain to the correct number of links to obtain the proper tension. Below you see Philip removing excess links in the chain before installation.

Removing Chain Links

Then he installed it. The next two photos show the lower and upper sprockets with the new chain installed.

New Lower Sprocket & Chain

Upper Sprocket New Chain

And that wraps up the drive chain installation. This thing will cover some ground now. I’ll put it this way, in 4th gear it runs as fast as you would want to go on a machine with hydraulic steering and no suspension. Anyway, running it as such seemed to amplify an existing problem we’ve been having with the engine, and that is the backfire from the exhaust when it’s under a load. It encounters a severe power loss when this happens. We’ve adjusted the ignition timing to no avail, so we’re leaning toward the possibility of carburetor problems or a sticking exhaust valve. But that’s for another day. Maybe sometime down the road you’ll see posts on the engine repair and of course the cosmetic restoration. But in the mean time, the machine still works good enough for the occasional small job.



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