Kubota Tractor Mod: Adding a ROPS Mounted Fan

Here’s how I added a removable ROPS fan to my Kubota L3901 tractor. It’s been a big help in keeping me cooler in hot weather!

First, I wanted a 12-volt fan that was screw mountable rather than clip-on and I preferred it be metal rather than plastic.  I found this little gem below on Amazon for $17.

Unfortunately, it is no longer available.  However, there are some almost identical fans available on Amazon for prices ranging from $25 to $38.  The links to some links to them are below:

Other items:

ROPS Fan Materials List (PDF)Download

Next comes figuring out how to mount it on the ROPS in a way that allows an easy way to put the fan on when I need it and take it off when I don’t.

I settled on using a piece of angle iron, cut from an L-beam.  Now this happens to be 3/8” thick but it certainly doesn’t need to be.  It just what I could get easily and for free.  This will become a versatile platform for other accessories.  In this picture, I have just finished drilling the holes for the u-bolts to hold it to the ROPS.

Speaking of which, I used 3/8” u-bolts 3” wide and 4” long.

The angle iron is mounted to the left side of the ROPS, just above the bend. It is 4” tall and the front face is 4” wide. And it is 6” long.  I cut a notch in the top of the face 1 and a quarter inches wide and 1-3/8” form the edge which centers it.  The notch is 3/16” deep.

I drilled and tapped a 10-32 hole, 2” from the edge and ¾” from the bottom. I also drilled 4 3/8” holes for the u-bolts, spaced as shown.  Oh, and I primed and painted it black.

To protect the ROPS finish, I cut a 4 by 4 inch piece of rubber sheet from a pond liner scrap to go between the angle iron and the ROPS.  I also put pieces of heat shrink tubing on the u-bolts for the same reason.

The fan is mounted to a 4.9” x 3” steel corner brace made be Stanley – same as the ones I used on the side LED lights.  Only I cut about an inch off the bottom, but that’s optional.

I used a 10-32 wing grip screw which screws into the 10-32 threaded hole in the angle iron. I also added a #10 star lock washer to keep it from come loose.

The fan is mounted to the corner brace with 3 half-inch long 8-32 screws.  The holes in the brace are tapped for 8-32.

The hook plate is made from a piece of 1 and 1/8” by 1/8” think steel flat bar I had on hand, but you could also make one by cutting up a 1” wide corner bracket.

The hook plate is 2” long with a half inch 90 degree turn down and it is spaced with a 3/8” gap from the corner brace to hook over the angle iron in the notch.

Finally, the hook plate is screwed to the top of the corner brace with three 3/8” long 8-32 screws and #8 star lock washers.  The holes in the corner brace are tapped for 8-32.

The hole for the wing grip screw is 1.5” from the edge of the corner brace, which centers it, and 3” from the top of the corner brace.

The fan plugs into the 12-volt outlet I installed when I added the auxiliary fuse box.

When not in use, I remove the fan and hang on the wall unit warm weather returns.

Note: Links to Amazon products are Amazon Associate links that won’t cost you any extra, but will help support my efforts with a small commission on qualified products. Thanks for your support!