Rotary Cutter bush hog not cutting

[SoGeorgia]

Is your PTO shaft turning? Does it sound like the blades are turning? If your mower won't lift either you have multiple problems.

 

[JDGirl]

PTO shaft is turning, but the 2 drive lines are not turning as well (very slowly). Seems as though some of the blades were working when I first started out, but then nothing was cutting. Also the mower won't lower and is permanently in UP position. After re-reading all of the posts on this subject, I'm thinking I will look for sheer bolt and make sure the blades are turning before jacking up the mower.

 

[Gary Fowler]

PTO shaft is turning, but the 2 drive lines are not turning as well (very slowly). Seems as though some of the blades were working when I first started out, but then nothing was cutting. Also the mower won't lower and is permanently in UP position. After re-reading all of the posts on this subject, I'm thinking I will look for sheer bolt and make sure the blades are turning before jacking up the mower.

Sounds like you have closed up your rate of descent valve that is usually located right below and in front of your seat. Turn it counter clockwise when facing the rear of the tractor and it should allow the hitch to drop.

Sounds like you have sheared a bolt if the PTO is turning but the blades are just slowly rotating. Look for a hole in the coupling closest to the bush hog gearbox. It should have one hole in it that will line up with the other half attached to the gear box. Likely it will take a 3/8" diameter bolt. Align the holes in both halves and insert a bolt that fits tightly into the hole and tighten it up. I like to put a jam nut on behind the first nut so it stays secure. Grade 5 bolt should work for you.

 

[JDGirl]

Sounds like you have closed up your rate of descent valve that is usually located right below and in front of your seat. Turn it counter clockwise when facing the rear of the tractor and it should allow the hitch to drop.

Sounds like you have sheared a bolt if the PTO is turning but the blades are just slowly rotating. Look for a hole in the coupling closest to the bush hog gearbox. It should have one hole in it that will line up with the other half attached to the gear box. Likely it will take a 3/8" diameter bolt. Align the holes in both halves and insert a bolt that fits tightly into the hole and tighten it up. I like to put a jam nut on behind the first nut so it stays secure. Grade 5 bolt should work for you.

Thanks Gary. I replaced the bolt this morning (not sure if it was a grade 5 or not). Unfortunately it was way to hot here to try out by the time I got home. I'm going to try the rate of descent valve next. Hope it is a easy to find as the shear bolt... I'm very new at this as I moved in with my mom after dad died, and my brothers and nephews would not show me how to use the tractor...we had to pay someone to put out hay each week during winter, until I finally got someone local to at least show me the BASICS. Now I just use my common sense and the internet! LOL

 

[JDGirl]

Okay shear bolt tightened this morning...mows for just a minute. The thing in the middle (PTO?) is turning rapidly but the 2 drive lines on each side are only moving slowly...not fast enough to mow. Blades are turning very slowly and don't appear to be in any bind. Could it be I need to put grease in the gear box on all three of those things (PTO AND DRIVE LINES)... Any other suggestions? Where do I put this grease? I see many possibilities.

 

[JDGirl]

Guess I'll go take some pics and start taking off one of the bolts and see what I come up with...probably start on top. Seems logical.

 

[TripleR]

Have you pulled the top plate and checked your gearbox? We have blown a couple and had to replace them.

 

[JimRB]

Read this owners manual. It may not be your model of brush cutter but it covers many basics that you should know.

If you have 1 sheer bolt you may have another 2 or 4, or 3 or 6 if you have a mower with two more gear boxes.

http://www.modernagproducts.com/images/15-RAPTOR.pdf

 

[JRobyn]

I'm not real familiar with multiple gearbox bushhogs, but from your symptoms, it sure sounds like something is wrong with the main/central gearbox since no power/rotation is being transferred to the secondary boxes. The gearboxes usually have an allen-head plug in the side where you put in gear lube (usually 90 weight gear oil), filled up to the bottom of the plug hole. But even if there was no lube at all in the gearboxes, they should still work to transmit rotation/power.

Either there is still a sheared through shear pin at the input shaft of the main gearbox (or possibly a slipping clutch if the bushhog is equipped with one), or the gears or a shaft inside the box is broken.

Some pictures would definitely help.

You might also try disconnecting the PTO shaft from the tractor and see what happens if you try to turn the shaft (still connected to the bushhog) by hand.

Best of luck!

- Jay

 

[JDGirl]

I managed to open up the three places where the grease goes and added some. Inside the gearbox looked okay...but I don't know what to look for. I may have to hire a professional if I blew the gearbox...