[Jeffery]

Am I going to hurt my engine killing it cutting trees?

I dont really mow much with this thing, I mainly use it to cut small trees in ditches, so it gets abused. I kill the motor now and then on the bigger diameter stuff.


Am I hurting the motor on my 2520? I dont really care much about the mower, I bought it to abuse.

 

[BOBL]

It's not a good thing to stall out the tractor under load. Buy a clutch and install it. Especially if you beat on that mower. You won't be happy if you break the crankshaft, bend a rod, or cause some other type of catastrophic failure. A clutch for that should cost less than $100.

 

[Old Machinist]

You don't need a clutch on a brush cutter. Check the shear bolt and replace it with a grade 2 if you want piece of mind.

I run a grade 5 in mine.

 

[2mtrucks]

Surely it has a shear bolt? My 30 year old Woods has a shear bolt and our new Land Pride a slip clutch. I would be more worried about an expensive PTO gearbox repair than an engine repair. But it could be just as expensive as an engine repair.

 

[theduke]

Go with softer shear bolt.

Get an over run clutch to also protect tractor pto.

Looks like a 5' mower maybe.

 

[MeagerHair]

If the engine is stalling someone probably dropped a grade 8 bolt in to replace the shear bolt. Get a few real sheer bolts or a slip clutch.

 

[rwmeyer]

A shear bolt or a clutch is good/needed... period! Both will do what they're supposed to IF correct! A shear bolt needs to be the correct harness/material and a clutch typically needs the correct adjustment/bolt tightness. BOTH can have the drive and driven plates rusted together and both become useless!

Annually, both should be dismantled and the drive and driven plates inspected or at least rotated by hand. They can then be reassembled correctly... proper torque on clutch bolts or proper grade AND tightness on shear bolt... after "tightening" a shear bolt should be able to be rotated by finger pressure. Bob

 

[Old Machinist]

Before you run out and buy a clutch shaft understand the maintenance that goes with it. Thay have a tendency to rust and stick if not disassembled, cleaned, and adjusted periodically. I personally have trust issues with them.

A shear bolt a a simple, almost fool proof, method of protection. There are a couple different designs but the most common is a 1/2*3-1/2 bolt that goes through the center of the shaft connection at the gearbox. Pull that bolt out and make sure the shaft rotates to misalign the bolt holes. Look for lines on the bolt head. Three lines is a grade 5. One or no lines is usually a grade 2. Five lines is a grade 8 and should never be used as a shear bolt.

I have seen mower manufacturers recommend grades 2 and 5. Most say grade 2.

Equally important on a shear bolt yoke is the retaining ring or C clip that prevents it from coming off when the bolt shears. When you remove the bolt make sure the yoke will move back and forth but doesn't pull off. The 1-3/8" retaining ring should be in a groove on the end to prevent that. These are hard to find if missing. Last I bought I had to buy a 25 pack from McMaster Carr.

 

[BOBL]

Here is a link to one of, if not the best, source for bolts you'll find. Amazing product inventory, amazing service, low prices, and lightning-fast shipment. I have been using these folks for years and have never been let down.

Bolt Depot - Nuts and Bolts, Screws and Fasteners online

 

[letmgrow]

If you are stalling the engine out it doesn't sound to me like you are hitting anything which should break a shear bolt. I would rather think what you are trying to cut is a little too much for the HP of your tractor.
My first suggestion would be to raise the deck as much as possible and make your first cuts with the deck raised. After you've done the area you want cut, lower the deck and cut the area the second time.
The mower you have is plenty large for your tractor.
Another suggestion would be to check your blades for sharpness. Maybe instead of cutting grass and weeds you are trying to beat them to death with dull worn out blades. Dull blades will eat up horsepower.
The advice you have gotten about checking the grade of the shear bolt is fine. I'd never run more than a grade 5.

 

[SulleyBear]

If the shear bolts aren't breaking and the mower is stalling the tractor engine, either the wrong shear bolt is in use, the trees are too large, the mower is being operated too low, with too much ground speed or some combination of all of these. You definitely do not want to allow the engine stalling to continue.

If that means another approach to dealing with the trees, such as cutting the larger ones with a pole saw or hand held brush cutter before running the mower, it should be considered. After all, its likely the engine is stalling once in awhile and not over and over when in use. If if is stalling over and over, its time for a bigger machine or different approach entirely...........

Chances are you know the size limit of the trees which are trouble. Plus it takes time for trees to regrow. I would avoid making the stalling of the machine anything which happens knowingly when using the machine. otherwise, you are far more likely to break something very expensive.