1 of 3 blades on mower not completely cutting

[dlundblad]

Guys help me diagnose this.

1 of the 3 blades of our Kubota G1800 doesn't cut the grass completely. It is the one next to the side discharge chute. For the most part I lived with it, but now it drives me crazy enough to fix it. It acts as if the blade is very dull or upside down.

The blades are new and the deck has a new OEM belt as well as a OEM tension spring. I sure thought I was onto something when I replaced that spring though. It was stretched about 2" longer than the new one.

Thanks.

 

[expat]

Switch the blades around, see what happens if the offending blade is sited in another position.

 

[boraticus]

Are you sure the blade is properly seated on the spindle?

Are you using mulching blades or regular blades.

Don't forget that the blade closest to the ejection side has to move all of the grass cut from the other two blades as well.

If cutting tall grass, try reducing the width of the cut. Cut maybe 2/3 of the width to see what that does.

 

[dlundblad]

Originally Posted By: boraticus
Are you sure the blade is properly seated on the spindle?

Are you using mulching blades or regular blades.

Don't forget that the blade closest to the ejection side has to move all of the grass cut from the other two blades as well.

If cutting tall grass, try reducing the width of the cut. Cut maybe 2/3 of the width to see what that does.


This is about the only way to do it. 2 of the 3 blades are doing the work while the 3rd one just flings it out. Seems like an odd solution though because other like models dont have this issue.

The mower has done this for a while regardless of the blades used. I can take them off, sharpen them and randomly re-install them and get the same issue. Even with new blades.

 

[440Magnum]

Sounds like a poorly designed deck where the discharge blade is getting choked by the cuttings from the other blades. I've owned two 3-blade mowers over the years, and neither had that issue.

 

[mrsilv04]

Have you checked the spindle for that blade? Take the deck belt off of the pulley, and make sure that it spins free with no slop in the bearings. Just verify that everything is the way it should be.

I was using a friend's POS Husqvarna rider to mow his yard when he was recovering from shoulder surgery, and had a spindle disintegrate while mowing. It was cheaply made of some sort of pot metal.

It did the same thing in the early stages of failure.

 

[bubbatime]

It's possible that you are cutting too much grass at one time. Set the deck up higher and mow in two passes. That third blade has to both cut the grass and throw all the clippings out from the rest of the deck too.

Are you using aftermarket blades (gators)? They dont work well on some decks.

 

[Kuato]

Outside the box, but does that blade turn the same direction as the other two?

 

[suspiciousmind]

With the mower off and key in pocket, reach through the chute and move the blade to see if it slips on the belt or not.

If there's not enough tension on the belt, it will slip on the pulley and the blade won't go fast enough to cut well while wearing out your belt at the same time.

Remove the spring and be sure the tensioner pulley is free to move about on its bracket. If it doesn't move freely, take it off and clean it up and grease it so it does.

If you have grease fittings on your spindles, give them eight or ten pumps each!

 

[Dallas69]

We had over a month of wetness so my Mom's place didn't get mowed until last Sunday.
The grass was over a foot tall and when I first tried to cut it I had this problem except hers didn't cut in the middle.
So I had to raise the deck to the highest setting and now smaller sections.
Pain in the a

 

[Lawn_Care]

Originally Posted By: suspiciousmind
If you have grease fittings on your spindles, give them eight or ten pumps each!



My thoughts exactly. If the spindle isn't spinning as freely as it should, that will cause the belt to slip on it's pulley and not cut as well. Definitely grease all the spindles. Even if it's not the problem, it certainly helps. If the spindles are sealed, you might look into replacing them.

 

[jhellwig]

Drive slower and let the deck do its work. Mow more often. Clean the deck regularly.

If there isn't a mechanical issue you might have to do one of the above.

 

[dlundblad]

I think the issue is fixed guys.

These tractors have 2 cup shaped washers that are supposed to face up and sit between the spindle and the blade that service as sacrificial bushing in case the blade hits something. Rather than the spindle exploding and destroying the blade, these just "break" free and become loose thus causing a not so tight connection between the spindle and the blade. The old bushings were shaped just like washers and have been as long as I can remember servicing the tractor.

I hit plenty of [censored] with this tractor as a kid so I imagine that had something to do with it.