Sickle Bar setup

[r laporta]

I have a JD #9 7' 3 pt Sickle bar mower. I put a new cutting bar in this year and it still clogs, and won't cut. The only thing I can see that looks to be a problem is that there is a 1/8 to 1/4" space between the knife and where it should ride on the rock guard. Is this space the problem? If so how close should they be, and how do I get them closer.

Thanks

Bob

 

[Greyhorse]

Either the guards are too worn or you need to adjust the hold downs (And/or replace them)..... couple taps with a hammer on my IH 1300 is the adjustment. Did you replace the wear plates too?

 

[r laporta]

The cut bar seems to be tight in the hold downs. It seems that the rock guards are worn or bent, but they are all the same. One person told me that the guards needs to be removed and put on a surface grinder so that the cut bar is almost touching the guard when they are reinstalled. Thanks again

 

[James Howell]

This is what works for me when replacing a knife on any of our <a href="http://www.youtube.com/watch?v=ZLND2DifdD0">JD sickle mowers</a>.

Starting on the end with the knife head; tighten the knife hold-down clip.

Check the clearance between the individual knife section and the ledger plate on the guard.

This clearance should be as close as possible without the knife clip rubbing/marking/dragging on the top of the individual section.

Pull the belt slowly to check for rubbing/marking/dragging on the top of the individual section.

Repeat this process for all 7 knife hold-down clips.

Operate the mower and check for smoke, friction, unusual/strange noise(s) at the cutter bar, knocking, etc.

One forum member suggested using a spray bottle with water to check for friction; spray and look for steam.

Hope this helps.

 

[GordoSD]

Yes,3/16 is way roo much space. Do you have the old single guards with the serrated ledger plates?
If so do you have smooth sections on the bar? And are the ledger plates looking real this?
The sections should be about .030 above the guards, that's the thickness of a matchbook.
They should be there without down pressure from the holddowns.Or darn close. If you try to "push them down 1/8 inch with holdowns you will just burn the holddowns up.
You can use a long cheater bar pipe to bend the guards up a little also.

 

[Phil - MO]

I just finished 15 acres with a JD no. 9 I'm setting up.  Just starting working good at the end. Have about 20 acres or more to do.If jamming on end replace sickle on end with the one and one-half sickle and new ledger plate on outer shoe.  I tried to buy the tool mentioned in my operator manual from the JD dealer to bend rock guards but the parts guy didn't know what I was talkng about. I don't quit see how cast iron guards can bend but what do I know.I replaced all the rock guards (old ones were really bad).  I hit each rock guard from the underside with ball peen hammer (watch fingers and sickle) until about 1/16" clearance on sickle. This will loosen he bolt so be sure and retighten and check and whack again. I was using rock guards from local farm store and not too impressed with quality.
If my wife isn't looking I'm going to have a disc or drum mower next near. We didn't have thick fescue in the old days, just native hay when we used the horse drawn sickle mowers. I used to pull these mowers behing a tractor and don't remember having the problems we have today.

 

[Anonymous-0]

The sickle cuts like scissors, not by inertia. There can't be a gap between the bottom of the sickle and the guard and cut grass. Corn stalks maybe, but not grass. All you have to do requires getting the guards and the sections together, may take replace sickle sections and guards. They do wear as do the hold downs.

Gerald J.

 

[Harry C]

On the rock guard is a removalable part called a ledger plate. This is the other half of the scissor action. The sections(the knives)on the moving bar cut against the ledger plate. If these are missing or really worn out it would give you this gap and it will not cut. If the ledger plates are missing you might see a hole down through the center of the rock guard where the rivet should be.