# DIY double hard bag grass catcher tune-up



## GoMopar440 (Aug 12, 2011)

Yesterday we picked up a used Craftsman double hard bag grass catcher (model# 917.248970) for our old Craftsman riding mower (model# 917.270710). I read quite a few online articles and watched Youtube videos about these grass catchers not wanting to work properly. Uneven filling seemed to be the most common complaint. The second biggest complaint was tube clogging for various reasons. Prepared with this knowledge, I decided to see what I could do to make it work better, and also to see if I could overcome those two biggest flaws.

At first I gave it a good cleaning inside and out to remove all the old grass residue. Afterwards I used an anti-static plastic polish on the insides of the upper and lower feed tubes to help keep the grass from getting hung up due to drag on the tube walls. Then I made sure the hard bags were assembled correctly and installed properly according to the owners manual. When I went to attach the tube, I noticed our mower didn't have the hook by the grass chute hinge for the bottom of the tube. I used the directions in the manual for installing the tube without that hook. Once it was all hooked up, I took it out for a test spin. The temps were mid 60's to low 70's and it was late in the afternoon on a clear day so the grass was dry.

From the results of that first outing, I noted a few glaring flaws. First, and most annoying thing was the same issue with uneven filling I had heard about. The bag on the left would fill all the way to the top of the cover while the one on the right would have maybe an inch of grass in it. When the grass piled in the left bag got high enough, it would plug the tube opening rather than allowing the grass to go into the right bag. This was a part of the reason for the second problem, clogged tubes, but it wasn't the only factor. I had to constantly readjust the end of the tube mounted to the mower deck or the grass would bypass the tube and go through the gaps. Those gaps also led to lower air pressure/velocity in the tube which also contributed to the clogging issue. At least after the test run it looked like the plastic polish on the inside of the tubes had done it's job. There was no grass residue hanging onto the tubes anywhere inside them.

To fix the uneven filling issue I looked at the exit end of the tube. It was long enough that the opening was right at the middle over the two bags. However, the opening was pointing mostly to the left, with very little of the opening pointing downward, and none facing to the right. to fix it I cut the end of the tube back so that when the grass piled up on the left, there would still be a sizable opening in the end of the tube facing towards the right bag. I tested it out it was only marginally better. I took a second cut until I ended up with the end of the tube looking like this. 









The second issue was addressed by modifying the connection point of the mower deck to hold the bottom of the tube tight against the deck opening. To do this I unbolted the folding grass chute and took a look at what I had to work with. There was a square plate under the chute mount, but it looked like it never had a hook on it. I used some scrap bed frame rail material to make a "L" shaped hook to fit the opening in the bottom of the tube. I welded that to the square plate first, and then welded another 1/4" wide strip of the same bed rail material to the tip of that hook. After it cooled down I cleaned up the welds, rounded off the top side of the hook and then gave it a coat of paint. After the paint was dry I reassemble everything. I could not get the bottom of the tube past the folding grass chute ot get it onto the hook. So, I decided to leave remove the grass chute and see if the tube would fit better without it. This goes against what the owners manual says ("leave the folding grass chute in place"), so I did this at my own risk. If anyone wants to try copying this mod, you will have to make that choice for yourself. Anyway, the bottom tube went on the new hook perfectly and that aligned the edges to the opening on the deck much better than before. This was the end result. 

















Now came the test run to see if all this work actually did anything to help or not. With the tube in this configuration I am able to get complete filling of BOTH bags. The new hook held the end of the tube in place securely with no signs of it trying to jump off the hook or slide out of position. Now the left bag fills up first and then the right bag starts to fill until both bags are full. I ran it like this for a few hours until it started to rain and I'd have to say that it's a qualified success.









I hope this helps some of those people with these bag setups get them to work better. We picked up this set cheap, not because it was broken or worn out, but because the previous owner gave up trying to get it to work. I better not tell him it didn't cost me anything but a little of my time to make it work like it SHOULD have from the factory.


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## BigT (Sep 15, 2014)

Thank you GoMopar440 for sharing this outstanding innovation/modification.


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