Attention people running Rockford PTOs. We’ve noticed recently a couple of clutch failures that could have been prevented. Here’s how you can save time and money if you are running a Rockford 4-25754 PTO.
The Rockford Model 4-25754 PTO is a spring-loaded clutch used behind Ford industrial engines on wood chippers. We support this PTO by stocking complete clutch kits which include a pilot bearing, a clutch disc with 6 springs, pressure plate, release bearing and installation tool. This Rockford PTO has a splined input shaft. Our sales of that shaft have increased. We didn’t know why.Read More
Foley Engines offers our customers both new complete Twin Disc, Rockford and WPT power takeoff assemblies as well as clutch packs. We stock them heavily and ship them daily across the US. We’ve found that sometimes people need a little help in deciding whether to buy a complete Power Take Off Clutch replacement or simply a clutch pack.
This Tech Tip shows you the pros and cons of buying a Clutch Pack versus a complete PTO. Here are some things to consider as you evaluate the best way to get
This Dr. Diesel™ tech tip is one of a series that we publish for the industrial engine community. It focuses on the Twin Disc IBF314 power take off clutch assembly and how to identify which one you have. Check out other Dr. Diesel™ Tech Tips including
Tech Tip #48: Maintaining Your Rockford and Twin Disc Power Takeoff Clutch,
Tech Tip #164: Upgrading Your Twin Disc/Rockford or Auto Clutch PTO, and
Tech Tip #205: Twin Disc or Rockford Not lasting as Long as it should? Here’s an Easy Fix
for more information on other power takeoff clutches.
The Twin Disc IBF314 is a heavy duty PTO assembly that is commonly used on large wood chippers, tub grinders, and other severe duty industrial applications where the mechanical style PTO would not hold up and would overheat. Unlike the SP314, the IBF314 has ventilated discs, larger main bearings, usually has an oil bath for the bearings and is a much larger, heavier duty unit.
But there are several variations to the IBF314 and the difficulty comes when ordering parts or replacement IBF314 PTOs. Ideally the Twin Disc inspection plate which lists the model and Bill of Materials (BOM), often called the “Bomb”, number is still on the housing. But after all these years, if the Twin Disc plate is missing we can still help. This Tech Tip shows you how to identify your IBF314 if you can’t find the BOM number by answering a series of questions we have developed over the years.
Determining Your Style of IBF314
Is your unit the oil bath style with a dipstick or the less common greaseable style? (Note: The greaseable style is often called the “CAT Style” because it is used frequently behind CAT engines.)
What is your Input Shaft size? Because the input shaft differs in size we need to know which one you have. The following two questions will help.
What is your Pilot Bearing size? Do you have an 80mm pilot bearing (i.e., a 3.07 bearing) or the more common 100mm bearing (i.e, a 3.09 bearing)?
Do you know the bore of the flywheel pilot bearing hole?
If you can’t determine the answer to Questions A and B, please look at the output shaft of your PTO for a stamped in number. That will tell us which input shaft you have.
What kind of discs do you have?
Do you have sintered iron discs or the more forgiving molded style discs?
If you have sintered iron discs, do you want to switch to the far less expensive molded discs?
The molded discs are not only less expensive but will work as well if not better than the iron discs which because they have some “give” to them and the teeth won’t break as easily. We have seen published technical research which validates the superiority of the molded discs.
Looking for more information on IBFs? We stock workshop manuals and could ship one out to you today!
This Tech Tip is one of a series we publish for the industrial engine community. It focuses on how to lubricate your Twin Disc or Rockford power takeoff clutch.
The chart below shows a good maintenance schedule for Twin Disc and Rockford PTOs.
To Lubricate your PTO
Operating Shaft: Grease every 3 months / 100 hours
Bronze Collar: Grease daily / every 10 hours
Sealed Bearings: Inspect every 2 years / 4000 hours
Shielded Bearings: Grease every 3 months / 100 hours
Main Bearings (oil) except SP311OP Series
To fill level on oil gauge or bottom of check plug
Every 8-10 hours. Drain and fill every 6 month / 1000 hours
SAE30 engine oil
Main Bearings (grease)
Every 8-10 hours
Number 2 grease (see below for new recommendation)
Add 1cc (1 shot)
Every 8-10 hours
Add 1cc (1 shot)
3 months / 100 hours
Pilot Bearings (periodic lube)
Add 1cc (1 shot)
3 months / 100 hours
Pilot Bearings (pre-lubricated)
Inspect every 2 years
Replace bearings as needed
1 drop required
DO NOT OVERLUBRICATE
Remember, less is more!
As always, don’t over-grease your PTO. While lithium grease is the standard recommendation for use in PTOs, we have recently found Lubriplate LTR-2 Red Grease to be superior. This rugged, tacky grease comes in No. 2 density and it can withstand higher temperatures than traditional lithium grease. Its zinc-free additive package provides good anti-wear protectionRead More
A fair number of people running a Twin Disc or Rockford power takeoff clutch in wood chippers and tub grinders tell us that they aren’t getting the life out of their power takeoff clutch that they should. Most of the time the issue is one of too much side-load on the PTO output shaft. This causes the output shaft to twist, overheat, and eventually fail. Sometimes the pilot bearing is deformed and the pilot bearing hole in the flywheel is ruined as well as the PTO.
Excessive side-load on a PTO output shaft can be caused by any number of factors. Maybe the PTO was never spec’d for a side-load and pulley application so it doesn’t have a pilot bearing to cradle and support an input shaft. Maybe the owner has installed too many pulleys too tight on his PTOs output shaft. Or, just maybe, the OEM installed undersize pulleys on the output shaft to get more power out of the engine package. In any case, excessive side-load is a common problem with Twin Disc and Rockford PTOs in certain wood chipper applications. But here is a way to minimize it.
In Foley Tech Tip #147: Running a Twin Disc/Rockford PTO? Want It To Last Longer? we discussed a PTO cradle system that a Twin Disc or Rockford owner could fabricate to prevent his PTO from twisting from high side-loads. We showed you a couple of photos of a two piece cradle set up. This Dr. Diesel™ Tech Tip goes a step further. Here we give you specific drawings and dimensions to fabricate a one piece cradle support plate. This one piece cradle should give you better support than the two pieces we presented earlier and the specific dimensions should make it easy for you to weld one up.
Twin Disc Side-Load Support Plate / Foley
PTO MODEL NO.
RECOMMENDED BOLT SIZE
ALL DIMENSIONS MEASURED IN INCHES
3/8-16UNC X 1½
3/8-16UNC X 1½
½-13UNC X 1¾
¾-10UNC X 2
¾-13UNC X 2
¾-13UNC X 2
BOLTS TO BE GRADE 8 / USE ½” STEEL PLATE FOR PART NUMBERS FOL326 FOL327, AND FOL328 / USE ¾” STEEL PLATE FOR PART NUMBERS FOL329 FOL330, AND FOL331
Too busy to fab up a side-load support plate for your Twin Disc? We now stock these cradle support plates and have them ready to ship. Just call us with the model number of your clutch and we can get one out to you in no time. (Before you ask how much a support plate costs, Dr. Diesel™ suggests that you should ask yourself what a failed PTO and a perhaps a ruined flywheel plus a lot of down time is going to cost you.)
Because we believe that Tech Support Matters™ we hope that you have found this Tech Tip on our anti-twist PTO support brackets helpful. We know that using a PTO support plate will extend the life of your PTO and help prevent damage to the pilot bearing hole in your flywheel.
#187: Notes on Installing Twin Disc/Rockford Power Takeoffs
When installing a new or re-manufactured Twin Disc® / Rockford power takeoff always change the pilot bearing (see Tech Tip #67, Installing a Rockford and Twin Disc Power Takeoff: How to remove a troublesome pilot bearing; Tech Tip #95, Installing a Rockford and Twin Disc Power Takeoff: Removing a troublesome pilot bearing, Part Two; Tech Tip #113, Prolonging the life of your Rockford and Twin Disc Power Takeoff).
After installing the PTO, you should check to ensure you have proper endplay, the clutch is properly adjusted and lubricated per the operator’s manual before starting the unit.
After installation use a soft hammer and rap the end of the output shaft to unload any pressure on the bearings.
Using high-grade lithium based grease, lubricate according to the following guidelines:
Rockford and Twin Disc Maintenance
Daily: brass throw out collar
Every One Hundred Hours: main bearings and unsealed pilot bearings
Manufacturers names, symbols and numbers are for reference purposes only and do not imply manufacturing origin.
When installing a new or remanufactured Twin Disc / Rockford power takeoff always change the pilot bearing (see Tech Tip #67, Installing a Rockford and Twin Disc Power Takeoff: How to remove a troublesome pilot bearing; Tech Tip #95, Installing a Rockford and Twin Disc Power Takeoff: Removing a troublesome pilot bearing, Part Two; Tech Tip #113, Prolonging the life of your Rockford and Twin Disc Power Takeoff).Read More
This Tech Tip is one of an ongoing series we publish to help people maintain their power takeoff clutches. See the following for helpful tips and examples:
Tech Tip #48: Maintaining Your Rockford and Twin Disc Power Takeoff Clutch,
Tech Tip #73: How to Make Your Twin Disc or Rockford Power Takeoff Last Longer,
Tech Tip #93: Twin Disc® and Rockford Power Take Offs or
Tech Tip #113: Prolonging the Life of Your Twin Disc or Rockford PTO.
We have collected these Tech Tips in a booklet titled Foley Engines Tech Tips: Helping with your Twin Disc/Rockford PTO Since 1916. If you would like us to send you a copy, please call us at 800.233.6539.
We stock and sell a large number of Twin Disc, Rockford, AutoClutch, WPT and PEC power takeoff clutches. Frequently, a customer will ask us to swap the drive pulleys from their old PTO clutch over to the new PTO. That’s when the fun begins. Because pressing pulleys on and off Twin Disc and Rockford clutch shafts isn’t easy, we have a two (2) hour labor minimum to do this job.
Over the years we’ve used a variety of techniques ranging from torches, beating off the pulley with sledge hammers, to using hydraulic presses to remove pulleys from Twin Disc, Rockford and AutoClutch PTOs. I’d like to share these techniques with you.
Using heat to remove a pulley from a PTO clutch output shaft is very straightforward. We recommend that if you don’t have access to a torch, you can pick up a weed burner for under $50 and try that.
2) Hydraulic Presses
Often on a larger PTO, such as a Twin Disc 318 or a Rockford 4-34510 or a Rockford 4-11060, a sledge hammer or heat isn’t helpful, and as a result many people turn to using a hydraulic press. Beware, though, of using the hydraulic press that consists of a bottle jack and an “A” frame with a sticker on it that says, “Made in China.” You’re going to need to put some serious pressure on the stubborn pulley and these $119 presses are very dangerous, especially with a large Twin Disc or Rockford PTO.
We have two OTC hydraulic presses in our shop. One is an air over hydraulic 55 ton press and the other is a hand actuated 12½ ton press. Both have functioning pressure gauges so the operator can see how much pressure he is applying. Other well-known brands include Nugier. Good, used hydraulic presses are easy to find at machine tool auctions and factory closings.
OTC has by far the largest assortment of pullers and spreader bars for removing pulleys. Some are used with an impact wrench. You can usually find an assortment of new OTC pullers for sale on eBay for roughly 50% off OTC list price. Snap-on has a 40 ton puller for $750 but we have never seen it.
4) Types of Pulleys
Customers bring their Twin Disc and Rockford PTOs into our shop with one of two pulley styles, either a tapered lock pulley or a straight bore-type pulley.
The tapered lock two-piece pulley costs a little more money, but it can be removed much more easily. You simply remove two set screws in the middle of the hub and then put them back in different holes. This will help you jack the pulley off using a wedge. If worse comes to worse, and you damage the pulley, usually only the center hub is damaged and that can be replaced. Before you remove the pulley, you need to reference the hub (not the pulley) when measuring the location where the pulley goes on the new PTOs shaft.<
Browning makes a good tapered lock two-piece pulley and if you damage a straight bore-type pulley you should consider replacing it with a Browning tapered lock pulley going forward.
5) Installing the Pulley on the New PTO Shaft
Okay. You’ve gotten the darn thing off the old shaft without breaking it. Now what? Carefully inspect the end of the output shaft on the new PTO clutch. Because the pulley is really pressed on the shaft (as an “interference fit” component) it is important that the new shaft is not banged up, have burrs, etc.
We recommend using what is called “Plumber’s roll” on the end of the new power takeoff output shaft. “Plumber’s roll” is a coarse aluminum oxide paper that comes in a roll 1” wide. You can use it to smooth the shaft out. Finally, you should lubricate the shaft.
We hope that this little Tech Tip will help you the next time you need to change a pulley on a Twin Disc, Rockford or AutoClutch PTO. Please call us toll free at 800.233.6539 for more information.
This is one of a series of Tech Tips we publish for the industrial engine community. This one focuses on power take off clutches; specifically Twin Disc, Rockford and AutoClutch power takeoff assemblies. It discusses how to get more life out of your PTO with a simple upgrade to your pilot bearing.
Earlier Tech Tips have discussed power takeoff clutch maintenance (see
Tech Tip #48: Maintaining Your Rockford and Twin Disc Power Takeoff Clutch
Tech Tip #93: Twin Disc® and Rockford Power Takeoffs
Tech Tip #116: Curing Excessive Side Load Problems With Twin Disc and Rockford PTOs and
Tech Tip #147: Running a Twin Disc/Rockford? Want It To Last Longer?)
and pilot bearing selection (see
Tech Tip #67: How to Remove A Troublesome Pilot Bearing (Part 1)
Tech Tip #95: Removing a Troublesome Pilot Bearing (Part 2)
Tech Tip #118: Super Sizing Rockford and Twin Disc or Auto Clutch Power Takeoff Clutch Pilot Bearings: Prolonging the Life of Your PTO – (Part 3) and
Tech Tip #158: Power Takeoff Clutch Maintenance: How to Remove a Troublesome Pilot Bearing (Part 3).
This Tech Tip focuses on enhancing the life of your Twin Disc, Rockford or AutoClutch power take off clutch by choosing the right pilot bearing. The pilot bearing on a power take off clutch is critical. It is inserted into the flywheel and is the important link between the flywheel and the Twin Disc, Rockford or AutoClutch PTO input shaft. Yet when servicing their PTO assembly many people either don’t replace the pilot bearing or seek the cheapest one they can find. We’ve often heard customers say as they leave our facility, “Naw, I’ll just take a new disc. I’ll pick up a Chinese pilot bearing at NAPA on the way home.”
What does AAMCO Transmission say in their ads, “Pay us now or pay us later”? People may have gotten away with using cheap pilot bearings when they were running low HP gas power units on an intermittent duty cycle. But today’s high horsepower diesels produce lots of heat and a cheap pilot bearing doesn’t last.
Big Horsepower, High Heat and Tiny Pilot Bearings
We’ve seen an increase recently in pilot bearing failures, especially in wood chippers running high horsepower engines coupled to Twin Disc, Rockford and Auto Clutch clutches. The industrial engines used in wood chippers are getting more and more powerful yet the size of the pilot bearing hasn’t changed. This is especially true of an AutoClutch PTO running behind a John Deere engine. The John Deere flywheel doesn’t allow much space for the pilot bearing. As a result it is relatively tiny. When it fails the results aren’t pretty and the owner is often faced with buying a new flywheel from John Deere. In case you haven’t priced out a John Deere flywheel recently, it could ruin your day.
We’ve seen so many John Deere flywheels ruined by a pilot bearing failure that we stock the most popular Deere flywheels used in wood chippers, PN RE25651 and PN R500219. Not only do we stock these flywheels we buy them right and can discount them to you. But here is how to avoid all that
Upgrading the Pilot Bearing
While you can’t change the size of bore in the flywheel allowed for the pilot bearing, you upgrade your pilot bearing. In earlier Tech Tips (
Tech Tip #73: How to Make Your Twin Disc or Rockford Power Takeoff Last Longer and
Tech Tip #113: Prolonging the Life of Your Twin Disc or Rockford PTO
we suggested that people stay away from Chinese pilot bearings sold in Chinese boxes. At a minimum, you should purchase your pilot bearings from a US bearing manufacturer. But here is new idea for longer pilot bearing and flywheel life.
We recommend that you use a Viton sealed pilot bearing in all high horsepower, high heat applications, especially in a wood chipper.