Agriculture has always been a cornerstone of the U.S. economy, and it continues to thrive as an essential industry. With over 3 million farms across the country, farming plays a vital role in providing food, fuel, and fiber for both national and international markets. Whether you're already part of the agricultural sector or just starting out, understanding the equipment that drives farming operations is crucial. One key component of this equipment is the PTO clutch, an integral part of many machines used in farming and lawn care.

At Ox Clutch, we’re experts in PTO clutches, and we're here to answer some of the most common questions related to this vital part of your machinery. From John Deere PTO clutches to Bad Boy PTO clutches and Woods PTO clutches, we offer a wide selection to keep your equipment running smoothly. Keep reading to learn more about PTO clutches and how they impact your farming or lawn care operations.

1. What is a PTO Clutch and What Does It Do?

A Power Take-Off (PTO) clutch is an essential component in many types of equipment, including lawn mowers, tractors, and other agricultural machines. It allows the engine’s power to be transferred to the attachment (such as a mower deck, baler, or other tools) connected to the machine. Without a working PTO clutch, your machinery won’t operate properly, leading to costly delays and maintenance issues.

Maintaining a reliable PTO clutch is critical for smooth operations. If you're using equipment like a John Deere PTO clutch, Bad Boy PTO clutch, or Woods PTO clutch, ensuring your clutch is in top condition will make a big difference in your machinery's performance.

2. How Often Should You Replace Your PTO Clutch?

The frequency of PTO clutch replacement depends on how often you use your equipment, as well as the conditions in which it operates. If you notice that your mower or other equipment is losing power or not engaging properly, it might be time to consider a PTO clutch replacement. Regular maintenance can help extend the life of your clutch, but eventually, wear and tear will necessitate a replacement.

If you’re concerned about the PTO clutch replacement cost, rest assured that we offer competitive pricing and PTO clutch replacement free shipping for your convenience. It’s an investment that will save you money in the long run by avoiding larger mechanical issues caused by a failing clutch.

3. What Happens if You Don’t Replace a Faulty PTO Clutch?

Ignoring a faulty PTO clutch can lead to significant problems. If your clutch isn’t working properly, your machinery may not operate as efficiently, which can increase fuel consumption, damage other parts of your equipment, or even cause a complete breakdown. In worst-case scenarios, a malfunctioning PTO clutch could render your equipment useless until it is replaced, resulting in costly repairs and downtime.

To avoid these issues, it’s essential to monitor your PTO clutch's performance and replace it when necessary. Our wide range of PTO clutches, including options for John Deere, Bad Boy, and Woods equipment, can help keep your machines running at their best.

4. How Can I Extend the Life of My PTO Clutch?

While regular replacement is inevitable, you can extend the life of your PTO clutch with proper care and maintenance. Here are a few tips to ensure your clutch stays in great condition for as long as possible:

• Regularly inspect your equipment for signs of wear or damage.
• Keep your equipment clean and free of debris.
• Store your equipment properly during the off-season to prevent unnecessary strain on parts.

By following these simple steps, you can reduce the frequency of PTO clutch replacements and keep your equipment working efficiently.

For comprehensive PTO Clutch troubleshooting and installation guides, check out our Technical Support resource page.

5. Where Can I Find High-Quality PTO Clutches for My Equipment?

If you’re in need of a new PTO clutch, look no further than Ox Clutch. We offer a wide selection of PTO clutches for all types of lawn and agricultural equipment, including John Deere PTO clutches, Bad Boy PTO clutches, and Woods PTO clutches. Whether you need a replacement for a commercial mower or agricultural tractor, we’ve got you covered.

Plus, when you purchase your PTO clutch replacement from us, you get fast and free shipping on domestic orders, so you can get the parts you need without the added cost. Check out our full product catalog to find the perfect clutch for your machinery. If you have any questions or need help finding the right part, don’t hesitate to reach out to us via our Contact page.

Conclusion

PTO clutches are a vital part of your lawn care or farming equipment, and understanding how they work—and when they need to be replaced—can save you time and money. If you’re dealing with issues like a slipping or faulty PTO clutch, consider the PTO clutch replacement cost as a small price to pay for keeping your equipment running smoothly. At Ox Clutch, we’re proud to offer high-quality replacements for a variety of brands, including John Deere, Bad Boy, and Woods.

For more information, or if you need help with your PTO clutch replacement, visit our FAQ page to get answers to commonly asked questions about shipping, warranties, and returns. We’re here to help keep your equipment in top shape so you can focus on what matters most—getting the job done right!

Most of the time, you only know something is wrong with your lawnmower when it's too late: to prevent damage in the first place, here are some of the major causes of scag clutch failure. 

The scag clutch is not adjusted
Your scag clutch in your mower needs to be adjusted every 500 hours of use, or at least once a year. If this type of electric clutch becomes too loose over time, or if the space between the plates is screwed on too tightly, this inhibits your drive shaft movement, thereby causing warping or vibrating.

Replace your old scag clutch if you notice any damage or bending.

You've used the clutch puller
It might have been an accident, or it might have occurred during an emergency: regardless, if your clutch puller has been pulled, your scag clutch is likely useless since this feature is designed to destroy the clutch as the last resort. 

You'll need to find replacement lawn mower parts before you get your mower back on the grass.

The clutch wire isn't grounded
Your electric clutch relies on clutch wires to dispense between 12 and 14 volts of electricity. Look for tears or fraying in your wires and ensure your second wires are connected to the engine block. If there is any sign of corrosion or rust on the wiring, it's time to replace the wiring before you buy an entirely new clutch replacement. 

If your clutch receives the electricity, but still doesn't work, it's time to get a scag clutch replacement or another type of replacement clutch for your mower. 

Improper belt installation
Mowers require belts to turn the blades. If you have a worn out belt, or if your belt is burnt in one or more places, you may simply need a belt replacement. The resulting changes in speed and deck positions often lead a mower owner to assume there is an issue with their clutch, however, the belt may be the issue. Get the correct belt for your mower and get it properly installed by a service professional. 

Rust build-up
Rust accumulation from a stagnant mower can cause an electric scag to freeze up. If you haven't used your mower for a few months, clean the rust between the plates and engage the clutch a few times to rub away leftover rust. Do this a few times before you seek out replacement clutches.

Before you make hasty decisions to replace your clutch, consider these options to rule out the possibility of clutch failure. When Americans spend nearly $16 billion on lawn care, it's essential you have the working parts to take care of your mower.

Let's talk about something we all want - a gorgeous lawn that makes the neighbors jealous. But here's the thing: even with the best intentions, some common mistakes could be sabotaging your curb appeal. Don't worry, though - we've got your back with some straight talk about what not to do.

Mistake #1: The "I'll Do Everything at Once" Syndrome

We get it - when spring hits, you're excited to transform your outdoor space. But here's a pro tip: trying to juggle multiple projects at once is like trying to mow your lawn blindfolded - it rarely ends well. Whether you're planning that dream garden, building a new deck, or redesigning your landscape, taking it one project at a time is the way to go. Trust us, your wallet (and your sanity) will thank you.

Mistake #2: Skimping on Professional Equipment and Maintenance

Here's a shocking number: Americans spend nearly $16 billion yearly on lawn care services. Why? Because they understand that quality matters. But even if you're a DIY enthusiast, you need the right tools for the job.

Speaking of equipment, let's talk about something that could be secretly sabotaging your mowing game - your PTO clutch. If you're experiencing rough blade engagement, strange noises when starting your mower, or inconsistent cutting performance, it might be time for a PTO clutch replacement.

Whether you need a Toro or a Gravely PTO clutch replacement, we've got you covered with quality parts and free shipping on domestic orders. Wondering about PTO clutch replacement cost? Check out our catalog - you might be surprised at how affordable maintaining professional-grade equipment can be.

Mistake #3: The "Wing It" Approach to Lawn Care

Look, we've all been there - seeing a beautiful day and jumping into yard work without a plan. But here's the truth: successful landscaping needs strategy. Before you start any project, you need to set a realistic budget, create a timeline, research proper techniques, and ensure you have the right equipment. A little preparation goes a long way in achieving those professional-looking results.

Ready to Level Up Your Lawn Game?

Don't let equipment issues hold you back from achieving that perfect lawn. If you're unsure about your mower's performance, contact our team for expert advice. We'll help you identify whether your PTO clutch needs attention and guide you to the right replacement part.

For shipping details, warranty information, or general questions about our products, visit our FAQ page. We're here to help you avoid these common mistakes and keep your lawn looking its absolute best.

Remember: A little planning, the right equipment, and proper maintenance go a long way in creating that showstopping lawn you've always wanted. And hey, if you need help with your PTO clutch, we're just a click away!

Essential Lawn Care Tips for Every Property Owner

Taking care of your lawn is about more than just cutting grass—it’s about ensuring your yard or commercial property thrives throughout the year. With the U.S. lawn care industry generating nearly $77 billion in 2016, it’s clear that maintaining a healthy, beautiful lawn is an investment that pays off. Whether you’re caring for a residential yard or managing a larger property, following a few key lawn care tips will help you avoid common mistakes and elevate your mowing routine.

At Ox Clutch, we know that the right equipment and quality replacement parts make all the difference. Let’s dive into some essential lawn care tips that will help you maintain your lawn like a pro!

1. Mow Consistently—Especially in Spring and Summer

Consistency is key when it comes to lawn care. During the growing season (typically spring through early summer), aim to mow at least once a week to keep your lawn looking neat and lush. If you miss a mowing session, the grass can grow too tall, leading to uneven patches and an overall messy appearance. During peak growth times in late spring, you might even need to mow twice a week for the best results.

2. Use High-Quality Lawn Mowers

Not all mowers are built the same. If you’re still using an outdated or second-hand mower, it’s time for an upgrade. A high-quality mower can make a world of difference in the efficiency, precision, and longevity of your lawn care routine. It will also help your mower handle the demands of frequent mowing.

And when it comes to keeping your mower in top shape, don’t forget about replacing worn-out parts, like your PTO clutch. At Ox Clutch, we offer a wide selection of PTO clutches for popular brands, including Cub Cadet PTO Clutch, Big Dog PTO Clutch, Hustler PTO Clutch, and more. Our parts are designed to ensure your equipment runs smoothly and performs at its best.

3. Regularly Service Your Mower

Even the best lawn mowers need maintenance. Regular servicing is crucial to keep your mower performing at its peak. For example, you should check and sharpen the mower blades regularly, as dull blades can damage your grass and leave it looking unhealthy. By staying on top of repairs and routine maintenance, you’ll keep your equipment running smoothly, which will pay off in the long run.

If you need a PTO clutch replacement, we’re here to help! Ox Clutch offers a variety of high-quality PTO clutches for different brands, including Warner PTO Clutch Replacement, Ogura PTO Clutch Replacement, and John Deere PTO Clutch replacements. We provide fast and reliable service, with free domestic shipping on all PTO Clutch orders.

For comprehensive installation or troubleshooting on your PTO Clutch Assembly, check out our Technical Support Resource page.

4. Adjust Your Mower’s Cutting Height Based on the Season

Mowing isn’t just about cutting grass—adjusting the height of your mower blades according to the season is essential. During the summer, raise the cutting height to allow your grass to stay healthy and better withstand heat. In spring or fall, lowering the blades will help achieve a cleaner, more even cut. Adjusting based on the season and weather conditions ensures your lawn stays healthy and vibrant year-round.

5. Don’t Forget About Replacement Parts

Over time, certain parts of your lawn mower will wear down, and the PTO (Power Take-Off) clutch is one of the most critical components. A malfunctioning PTO clutch can affect your mower’s performance, leading to frustrating issues like blades that won’t engage properly. If you’re facing these problems, it’s time to consider a replacement.

When calculating the PTO clutch replacement cost, remember that choosing high-quality parts can save you money by preventing further damage down the line. At Ox Clutch, we offer a range of affordable PTO clutch replacements, including Big Dog PTO Clutch and Hustler PTO Clutch models. Plus, we offer free domestic shipping to get you the parts you need quickly.

6. Learn More About Lawn Care and Equipment

If you’re looking for expert knowledge and reliable replacement parts, Ox Clutch is your go-to source. We understand that lawn care can be complex, but with the right tools, parts, and guidance, you can take your lawn care routine to the next level.

Check out our full product catalog for all the PTO clutches you need, and be sure to visit our FAQ page to find answers to questions about shipping, warranties, returns, and more. Need additional assistance? Don’t hesitate to reach out through our Contact page. We’re here to help!

Ready to Mow Like a Pro?

By using the right equipment, keeping up with regular maintenance, and making a few simple adjustments, you can ensure your lawn care routine stays on track. Say goodbye to amateur mistakes and get ready to mow like a pro with Ox Clutch’s top-quality PTO clutches and expert support. Browse our selection of PTO clutch replacements and get started today!

Owning a farm is a dream for many, with nearly 87% of U.S. farms being family-owned. If you’re planning to start your own farm, it’s exciting, but there’s a lot of work ahead. From managing crops to maintaining equipment, careful planning is key to long-term success. Here are three must-know tips to help you get your farm off the ground and set up for a thriving future.

1. Create a Solid Business Plan

Your farm is your business, so treat it like one from the start. Having a well-thought-out business plan is essential. You’ll need to map out where you want your farm to be, the opportunities it will provide, and the challenges you may face along the way. Financial planning is critical—ensure you have a solid budget and avoid unnecessary debt. Managing your farm like a business will help you navigate both the ups and downs of farm life.

2. Invest in Quality Lawn Care Equipment

Once you’ve secured your land, it’s time to focus on equipment. Without the right tools, even the best farmland won’t reach its potential. Start by acquiring quality lawn care equipment that suits your needs—mowers, tractors, excavators, and other essential farming tools.

When it comes to lawn mowers, having reliable equipment can make all the difference in your daily operations. Investing in high-quality machines from the start ensures you’ll have the right tools for the job. But don’t forget about the importance of maintaining your equipment to keep everything running smoothly.

3. Stay on Top of Equipment Maintenance

Proper maintenance is the backbone of any successful farming operation. Whether it’s keeping your mower in top condition or addressing PTO clutch issues, don’t neglect your equipment’s needs. A failing PTO clutch can seriously disrupt your farming operations, especially if you rely on it for tasks like mowing fields or cutting grass.

If your PTO clutch starts to show signs of wear—such as blades not engaging, unusual noises, or slow start-up—it’s time to consider a PTO clutch replacement. Ignoring these issues will only lead to bigger problems down the road.

At Ox Clutch, we specialize in providing top-quality electromagnetic PTO clutches for all your lawn equipment needs. Whether you need a Warner PTO clutch replacement, Ogura PTO clutch replacement, or a Cub Cadet PTO clutch, we’ve got you covered with parts that are engineered for durability and peak performance. We also offer free shipping on all domestic orders of PTO Clutch Replacements to make your purchase even more convenient. You can browse our full catalog here.

Additional Resources

Our FAQ page is a great resource for information on shipping, warranties, returns, and other common questions about maintaining your equipment. If you need more detailed guidance feel free to reach out to our team via our contact page, or find comprehensive resources on our technical support page.

By staying on top of equipment maintenance and investing in quality parts like the Big Dog PTO clutch or Hustler PTO clutch, you’ll ensure your farm operates smoothly for years to come. Don’t let equipment issues slow you down—keep your farm running efficiently with the right care and the right parts.

Ready to get your farm started on the right foot? Check out our full selection of PTO clutches and let us help you keep your equipment in top shape!

Congrats on buying your first home! But you should know that you're not out of the woods in terms of purchasing just yet. Clearly, the property itself will be your most expensive purchase, but there are plenty of other things you need to make sure you're budgeting for throughout your first few months as a homeowner. 

Here are some important purchases for first-time homeowners: 

1. Furniture -- It might sound obvious, but a lot of first-time homeowners neglect to save up for any furniture items while purchasing a home. Moving into a new place with no furniture inside it can feel quite strange and actually mess with your mood. So it's best to start saving up for furniture, especially in the bedroom and living room.
 
2. Swisher lawn mowers -- Approximately 85 million households in the U.S. have private lawns. Whether or not you have a large property, a private property, or only a backyard, you're going to need a high quality lawn mower to keep your property looking great. Many homeowners forget about the importance of a lawn mower early on and can have an overgrown lawn in a matter of weeks. Make sure you're properly budgeting for Swisher lawn mowers so you can get to work maintaining your property.
 
3. Repair items -- Even if your house was just constructed, it'll only be a matter of time before you need to bust out the hammer and start working on some repair projects. That's why you'll need a quality toolbox equipped with plenty of assorted screwdrivers, pliers, wrenches, tape measures, and other essential tools.
 
4. Lighting fixtures -- A home without lighting, like a home without furniture, can feel quite depressing. You don't have to spend a significant amount of money on luxurious chandeliers, but you should find some quality lighting fixtures to improve the look and feel of your new home.

If you want to check out some replacement lawn mower parts or are in need of electric clutch replacement for your Swisher lawn mowers, give Ox Clutch a call today. 

The United States Lawn Care industry earned roughly $77 billion of revenue in 2016. From major landscaping jobs on commercial real estate sites to lawn mowing on smaller residential properties, clutch repair and replacement is an essential part of the lawn care sector. 

Ariens electric clutches are some of the most efficient and popular products across the entire landscaping industry. Hopefully this guide will help you better understand the ins and outs of electromagnetic clutches and how important electric clutch repair is for maximum performance. 

Electromagnetic clutches: what are they?

These clutches utilize both electrical and mechanical aspects to fully operate. Overall, the clutches operate electronically but actually transmit torque via mechanical processes. There are a few types of electromagnetic clutches in use across the country, but one design remains supreme: the single-face electromagnetic clutch. In fact, single-face clutches currently make up roughly 90% of all clutch sales across the market. 

Various uses for electromagnetic clutches

There are three main applications for clutches: machinery, automotive, and locomotive. 

• Clutches applications for machines -- This style of clutch is typically used for copy machines, conveyor drives, packaging equipment, food processing, and factory automation. But the primary machine use for clutches is for lawn mower purposes. Without quality Ariens electric clutches inside lawn mowers, landscaping would be a much more difficult task at any level, both commercial and residential.
  
  
• Clutch applications for automobiles -- Clutches are also commonly used for automobiles, consisting of a clutch release switch inside the gear level. The driver is required to operate the clutch swift by holding the gear level and changing it accordingly.
  
  
• Clutch applications for locomotives -- Electromagnetic clutches are also commonly found in diesel locomotives. In both light and heavy locomotives, power transmission has always been a primary concern. Thankfully, since clutch technology has improved dramatically over the years, these large vehicles are able to operate much more efficiently.

Importance of clutch repair and replacement

Unfortunately, clutches often have a short lifespan if they are utilized on a regular basis. If you're frequently using a high power machine or any kind of lawn mower, you need to make sure you're taking the equipment to trusted clutch repair services. Additionally, if you mower's performance is in need of a significant upgrade, purchasing a replacement clutch is your best bet in order to improve performance and save you money. 

If you're in need of Gravely PTO clutch repair and Gravely PTO clutch replacement, or want to learn more about general clutch repair for Swisher lawn mowers, as well as find high quality Ariens electric clutches, give the professionals at OX Clutch a call today.

The purpose of burnishing is to allow the two surfaces to become accustomed to each other before high RPM and load is applied while mowing, which increases the torque loading of the clutch. This insures better engagement of the clutch mating surfaces and prolongs clutch life.

To burnish a clutch, reduce the engine speed to about half. A typical burnishing time will take anywhere from 5 to 30 cycles depending upon inertia. The burnishing frequency should be done at 2 to 6 cycles per minute. Frequency of cycles and amount of cycles required will depend upon inertia. Typically the larger the inertia, the fewer cycles per minute allowed, and the fewer overall cycles required.

 

By: JAMES D. KLANN of Stearns Div., Rexnord Corp. | Motion System Design

Mostly, electric clutches and brakes run for hundreds of thousands of cycles with little watching. Overlook a few of their basic needs, however, and these normally unassuming devices can suddenly protest

Though clutches and brakes differ in purpose and application, for troubleshooting and problem-solving purposes their operating principles are similar. We focus here on positive-action units that are either electrically or mechanically actuated (“spring-set”), which includes brakes with On-Off action and Start-Stop clutches.

Most problems in the field show up as overheating, torque loss, or coil failure. Unless you dig until you find the culprit, you’ll probably keep replacing failed parts that result from the problem, without resolving the problem. Here are some tongue-in-cheek guidelines to help you.

Fail to read instructions

It has become a cliché: “When all else fails, read the instructions.” The fact: Clutches and brakes are precision devices with close tolerances. For troublefree service, they may have special assembly, installation, or adjustment requirements you must not overlook. When replacing a unit, even with one that looks the same, don’t just pull the old unit and slap in the new one. Instead, “before all else fails, read the instructions!”

Likewise, some sizes or designs have procedures for adjusting the air gap as it increases because of wear, or procedures for replacing components as they exceed wear limits. If you fail to follow all the maintenance and adjustment procedures in the instructions, you may not ruin your clutch or brake immediately, but you can be sure you’ve shortened its life.

Misalign it

Most electric brakes and clutches are installed in a direct-drive configuration, and alignment is just as important as it is with a motor. If bearings and shafts are not aligned, extra stresses and vibrations that develop can turn into major problems. Most industrial clutches and brakes are similar in design and have a small air gap between armature and magnet body. The effect of any misalignment is magnified, particularly on clutches, and can cause vibration and torque loss.

When you install or replace clutches or brakes, be aware that there are NEMA specifications on how they fit to motors or gearboxes, governing tolerance ranges for things such as register and bolt circles. Brake and clutch manufacturers set their design criteria to be compatible with this “window,” and proper alignment is normally the equipment manufacturer’s responsibility. You can incur trouble when mounting a new brake or clutch on used equipment if you don’t assure that motors or drives remain within NEMA tolerances. If the motor end bearings are worn, any shaft wobble will be exaggerated farther from the motor where the clutch or brake may be mounted — and what is really a motor problem may first show up as clutch or brake failure.

To avoid trouble, measure shaft runout both axially and radially, and check it against NEMA tolerances. These are usually around 0.004 in. radially and 0.002 in. axially, but they vary some by motor size. Also, check motor-shaft end float. Most equipment can tolerate float up to about 0.020 in. Most manufacturers’ instruction sheets include allowable indicator runouts for mating equipment.

Overhung loads can cause trouble. Particularly on clutch applications with a sprocket or sheave, there is a limit to the side force or tension you can apply without overloading the bearing and deflecting the output shaft.

If a unit has a retaining bracket, don’t bolt it down tightly or weld it in place unless you want premature failure. The retaining tab is mainly to prevent rotation when the clutch is applied, and it is necessary only to pin it in place so it is somewhat free-floating. Bolting it tightly can create hub-and-shaft misalignment and bearing prestress. This can lead to quick clutch failure and even drive damage.

Misassemble it

We’re back at “read the instructions,” but repair or replacement of a clutch or brake presents many opportunities for misassembly.

Setscrews are a simple but often-overlooked example, if calls from the field are an indication. You’ll find them on driven hubs of components that mount to motor shafts. Depending on component size, components may be keyed only or keyed and secured by setscrews, especially on larger units. Fail to read about them on the instruction sheet if you want failure in the future.

Some brakes and clutches come with features such as special sealing and plated components for washdown applications, such as those in the food industry. Replacing plated fasteners or other components with unplated items will accelerate rust and cause early failure. Finally, replacing components such as friction discs with nonoriginal parts may drastically change operating characteristics. Use components not designed and tested with your specific brake or clutch and you may compromise performance. A replacement friction disc may look like and fit like the original, but it could have a much different friction coefficient and shorter life, for example.

Shake and break

Two types of vibration can trouble your clutch or brake. Operating vibrations from uneven loads, poor alignment, or misassembly will obviously destroy a unit if left unchecked. These phenomena are often cumulative, growing larger as they cause wear or loosen mountings. More subtle are environmental vibrations, caused by other adjacent or mobile equipment. Particularly when machinery having clutches or brakes with ball or roller bearings is stored or inactive for a long time, these vibrations and the bearings’ static loads may cause “false brinelling.” Result: Tiny dents in the bearing raceway. They will cause vibration and wear as rolling elements pass over them when the clutch goes back in service. The easy solution: Periodically turn the shafts on which the units mount — maybe once a month. It can improve the health of motor and line-shaft bearings, too.

Forget about storage

For a really bewildering and embarrassing experience, neglect any care of clutch and brake units waiting to replace spent compatriots or to go on your new products. A poorly protected clutch or brake waiting in the tool crib or storage room can get hurt. Avoid on-shelf vibration. Also, a well sealed and stored clutch or brake can be kept indefinitely. Normal factory packaging should be enough for about three months’ storage in an area without environmental control. For longer storage, a unit should be sealed in an airtight container with a desiccant to entrap moisture that may remain in the package, thus preventing rust. Superficial rust won’t hurt operation, but if rust is heavy enough to cause some armature deterioration, it can cause uneven pull and reduce the unit’s torque. Also if, because of rust particles, the unit does not seat properly, it could drag and generate excess heat.

Give it the wrong voltage

Torque depends on the coefficient of friction of the plates and also on the amount of pull force between the armature plate itself and the magnet body and coil assembly. Pull is a function of the coil’s specific voltage rating. Decreasing coil voltage reduces clutch torque so, where full torque is required, be sure full rated line voltage is supplied. When reduced torque is necessary, you can control a unit by means of an adjustablevoltage rectifier for the coils.

A more damaging mistake than applying the wrong value of voltage, though an easy one to make, is to apply ac voltage across a dc coil. Though most brake and clutch coils operate on dc, the manufacturer can supply them with a rectifier that lets them use ac line input. In some applications, a dc coil may operate (inefficiently) on ac for a short time before it fails. That can throw troubleshooting efforts off the track by making the failure look like an equipment fault.

Size it wrong

This misguideline applies less to the original equipment designer; more to the equipment repair specialist; and even more to the equipment redesigner and rebuilder. They can meet problems when a clutch or brake is replaced or when the equipment on which it serves is used for an application that differs from its original.

If the unit is too small for the torque requirement, it may work for a while before exceeding thermal capacity. Though the problem may seem like simple component failure, look further if a clutch or brake appears to lack thermal capacity. If it can’t dissipate heat quickly enough, you may need a larger unit. A solution may require close cooperation among makers of the equipment and of the brake or clutch, as well as the user.

You can also drive a brake or clutch beyond thermal capacity by failing to size it for high cycling. And heat buildup caused by any combination of high inertial load, rapid operation, and friction may be compounded by high ambient temperature. Make no mistake: Failure will result if the unit’s thermal capacity is exceeded.

Burnish badly

Most units are designed to burnish or run-in quickly in normal running. Others may be factory preburnished or available with optional preburnishing. Unless clutches and brakes are burnished properly, they may not deliver rated torque.

On standard brakes and clutches, inner and outer poles may extend a few thousandths of an inch past the frictionlining surface. This is normal, and the excess material will generally wear down properly after a short period of normal use. However, take care on lowspeed applications. If a clutch is burnished at low speed, say 200 rpm instead of 1,800 rpm, and the armature is not hardened, it could gall or “tear.” If the clutch or brake is not properly burnished, the friction material may not seat properly, and then the unit will never deliver rated torque.

When a brake is used on a PC or PLCcontrolled application, the load may be electronically driven to a stop before a brake sets, so it sets at zero speed and does not burnish at all. Many adjustablespeed motor drives have dynamic braking in which, during a slowdown or stop, the motor becomes a generator, putting power back into the utility lines. The “generator” load itself acts as a brake.

Use a friction clutch as a slip clutch

Friction clutches described here are not designed to slip or “feather” a load as does a slip clutch, which is intended for soft starting or downline equipment protection. Instead, they are designed to produce the minimum torque needed to keep the input and output shaft locked together in On-Off fashion. The more they slip, the faster they wear and the more heat they produce, because of the excess friction. Avoid this by sizing the unit for maximum torque needed to drive the output. Then apply a service factor, generally 1.5 to 2, or maybe even 3, depending on the application.

Forget the work environment

When lubricant or other material that can change the friction coefficient gets between friction surfaces, up to 75% of torque can be lost. It’s easy to notice large-volume contaminants — big gobs or clumps — but some are more subtle, such as lubricant from a chain drive. Near equipment that gives off contaminants, install a brake or clutch shroud.

Environmental and service conditions that can cause trouble for brakes and clutches include exposure to:

• Wetness or dampness, like steam.
• Gritty dust, like grinding fines.
• Oil mist.
• Salty air.
• Radioactivity.
• Chemical fumes.

Also, poor ventilation for a brake or clutch can raise its temperature and bring on trouble. If the unit is overshrouded or crammed into a tight cabinet, for example, it may suffer needlessly.

Another caution is the opposite of what you might expect: In early operation, do not blow out excess dust that accumulates. It helps maintain the right torque and improve any necessary burnishing. Sometimes you can be too clean.

Don’t recheck before you call

Often, you can blow a simple oversight into a much bigger production. In one case, a noise problem on some equipment brought a call to the clutch manufacturer. After a service call involving several people and many hours of downtime, the problem was traced to the installer’s failure to tighten setscrews — as described in the instruction sheet. By one estimate, 20% of trouble calls could be avoided by just reviewing instructions.

If you really want such problems, of course, misfile the instructions. Better yet, have no file for such items. Make sure they get lost or scrapped quickly, preferably even before installing the unit or storing it. For special fun, throw away the packaging before storing so you can’t tell readily what unit you have.

James D. Klann is Field Service Manager, Stearns Div., Rexnord Corp., Milwaukee.

By Chris Stevenson

Testing the PTO clutch should be done with caution, using proper safety steps.

The power takeoff clutch, or PTO, on a small engine uses electricity to engage a clutch to the main engine crankshaft. PTO clutches transfer rotational torque and power, typically used on small tractors to activate mower blades or tillers. The battery sends voltage to a magnetic armature and rotor, which engages the clutch and plate, allowing full contact. Problems arise when the clutch jams solid, slips excessively or the voltage becomes lost. A tractor owner can initiate a few tests to see if his PTO clutch functions properly, engaging and disengaging at the proper time.

Lift the utility vehicle up with a floor jack. Place two jack stands under the front frame and two jack stands under the rear frame, so the wheels sit above the pavement. Provide enough clearance to look under the mower deck and see the clutch drive assembly. Refer to your owner's manual for the battery location. Some riding seats tilt up for battery access. Place the positive lead of a voltmeter on the red, positive post on the battery.

Place the negative voltmeter lead on a good engine source. Read the volts. If the battery output indicates 12.5 volts or below, charge the battery. The PTO clutch will not engage without sufficient voltage.

Look for the in-line fuse between the electrical wiring harness from the lever switch to the PTO clutch assembly under the deck. Unscrew the cap wires to the fuse and look at the fuse filament. If the fuse appears black or the filament has blown, replace the fuse with the same ampere rating as the original.

Start the engine and let it warm up. Activate the lever to engage the clutch. From a distance, look underneath the deck and check for mower blade operation. If you hear a squealing noise, shut the engine off and remove the ignition key. Disconnect the negative battery cable with a socket.

Slide under the mower deck and remove any broken branches, twigs or other obstacles that might have jammed between the pulley and drive belt. Check the belt for tension by engaging the lever and feeling the tension on the belt. Replace any frayed, cut or worn drive pulley belts. Make the sure the idler pulley moves freely back and forth on its swivel.

Reconnect the negative battery cable with a socket. Insert the ignition key. Start the engine. Activate the PTO engagement lever, then disengage it. Turn it on and off several times. If you do not hear a disengagement noise or see the power takeoff pulley stopping or slowing down at any time, it indicates the clutch and plates have galled together from excessive heat, or the slip ring has jammed. This will necessitate a clutch removal and internal inspection.

Pull off the main power wire that goes to the PTO clutch assembly. This is located on the clutch side. Turn the wire jack toward you, but pull yourself back away from the deck as far as possible. With the battery connected and engine turned off, place the negative alligator lead of a test light to a ground source. Place the probe of the test light inside the wire connector, attaching it to the red lead that leads to the PTO clutch.

Activate the PTO clutch lever and look for the bulb to illuminate from the test light. No illumination means the engagement switch has failed at the lever-switch position. If the battery voltage reads correctly and the in-line fuse checks out, the lever switch will be the problem.

Use wire strippers to cut a length of jumper wire that will reach from the positive post on the battery to the red power lead inside the PTO wire jack. Make sure you connect the battery cables. Connect one end of the jumper wire to the positive side of the battery and the other end to the positive, red wire inside the PTO wire jack.

Listen for the click of engagement. If you can hear nothing, the problem lies within the electrical circuit of the PTO clutch assembly, most likely at the rotor and armature location.

Tips & Warnings