Bushed Cast Steel Alloy Pulleys

Note: The following information was retrieved from UtterPower’s archived pages. All information is republished for educational purposes. Any mention of items for sale or prices are outdated and no longer applicable.

Pulleys for the Lister and Big Flywheels

Utterpower PulleyMany DIYers will know that utterpower was the first to offer DIYers the 8.x inch Pulleys specifically designed to drive 4 pole generator heads off Lister and other big flywheels. Many of these have been put into service over the years, and we have noted that others have developed their own versions of these pulleys. Our pulleys are designed for Marine service, no expense has been spared period. When we learn how to make it better, we do it. Oh, you noticed our pulleys use a bushing that covers a wider range of shaft sizes? that comes in handy more often than you’d think.

Belts are typically $28 and up at any automotive store in lots of lengths, belts and pulleys will carry two or three times the load we typically use them for and never slip or chirp properly tensioned. Part of KISS is using simple, proven, readily available and cheap wear components. We have customers who claim 6000 hours plus on the same belt.

This 3rd Generation Utterpower pulley uses CNC and American QC and supervision. We believe that we have made a huge step forward in quality and performance of the pulley. It was important that we address the requirements of those who find themselves in marine and tropical settings, the pulley is plated as a final step. Yes it was a pain to go thru all the steps necessary to apply the plating, and it certainly did add to the expense. This effort incorporates special features, some not so obvious, but you’ll likely appreciate the effort to include them. One thing for certain, it was our goal to build the best pulley possible, and cost was a last consideration. This is not one of those products with a high mark up….it was designed by DIYers for DIYers, and we have used the same philosophy as we use in the direct drive, when it is obvious that we can make it better, we do. We leave behind two earlier versions of pulleys that DIYers here and in the third world can copy and make for themselves if they have the machine tools.

Now that we are confident of the design and new features, we are adding different sizes to the line up to provide certain drive combinations. Drive kits for 6/1_ST5, and even a drive system for the Yanmar 10hp clones and PMGs are in stock. More will be stocked in the near future.

Pulleys are made for both 50HZ and 60HZ, and there are many combinations that one can come up with for various requirements. Our line of pulleys will continue to grow, and we expect to develop drives that will handle considerably more torque and horsepower. some of the features in these pulleys support future offerings, they are fully backwards compatible, but they will also offer some advantages we will not discuss at this time. MORE sizes are in the works.

Some Pulleys that were offered at UtterPower:

  • 11.25 inch 8 groove Cad Plated 40 pounds!  (Sold Out)
  • 10.0 inch 8 groove Cad Plated sized for 50hz machines (Lister 6/1>4 pole heads)
  •  8.4 inch, 8 groove 20 pounds, Cad plated   (Sold Out)
  •  7.0 Inch, 8 groove, Cad Plated
  •  5.0 inch, 8 groove, 5 pounds, Cad plated, sized for SK bushing
  •  4.2 inch, 8 groove, 3 pounds, Cad plated, sized for SK bushing
  •  4.1 inch, 8 groove, 2 pounds 10 oz, Cad plated, sized for SK bushing
  •  8.4 and smaller pulleys, priority shipping and handling with tracking
  •  Good Supply of 38mm and 42mm SK Bushings

I have some inventory left, so feel free to leave me a comment as you never know what I might have in the shop.

Watch a Video of a Modified Pulley

This is a video of a modified 8.4 inch 8 groove serpentine pulley bolted to changfa flywheel.

Bushed Pulleys

Why do I use bushed pulleys, isn’t it just another expense?

Bushed pulleys; as far as I’m concerned, they are an important part of ‘KISS’ engineering. a bushed pulley is something that can be used on a range of shaft sizes. I use the ‘SK’ sized bushing because it covers the range of sizes we DIYers normally find ourselves involved with. There are a few using the 48mm shafts, and the SK bushing covers this rather large size as well. If we step up one size to the SF bushing, we can even cover a 2 inch bore, this is the size of the Lister 6/1 crankshaft!

Bushed pulleys allow us to attach a pulley to a shaft with a VERY positive fit, if you do it near right, it’ll never slip, it’ll never come loose, you won’t mangle a key way, and you can remove the pulley in sub zero weather with gloves on! Standard Bushings have two sets of hole in them, one can be used as ‘pass throughs’ the others are threaded. What you need to know BEFORE you install a bushed pulley is that one set of these holes are used as >JACKS< to ‘JACK’ the bushing back out of the pulley. This is typically done when the pulley is put on the shaft first, widest part of the hole facing the end of the shaft. Then you fit the ‘SPLIT’ tapered bushing on to the shaft small end first.

Some folks new to tapered bushing can’t get the new bushing on, always check the shaft and the bushing and make sure they are the same size. Once you are sure of this, you will note that the bushing often needs to be opened up a little. Simply slip a screw drive in the slot, and gently tap on the butt of the screw drive until the bushing spreads enough to get it on the shaft.

Bushed Pulley


Here’s a Metric ‘SK’ sized bushing, if you look close you might see the SK followed by the size. You’ll also note six holes, three are larger and un threaded, three are threaded


The archived images from the rest of this post are not retreiveable, but if you need more information on what you need to know before installing one, just send me a comment!

George B

This entry was posted in Bushed Pulleys, Z UtterPower Archives and tagged , , . Bookmark the permalink.

18 Responses to Bushed Cast Steel Alloy Pulleys

  1. Waldo McIntosh says:

    Hi George, I bought an 8 inch allmand serpentine pully a couple of years ago, and want to know is an 11.1 or even 11 inch even pulley available? If not do you know where I can get one? Thanks–Waldo

    • George B. says:

      Waldo, I do have a few 11.25 inch pulleys, they weight 40 pounds, As for 11.1, or 11.00 even, you could buy one and have Allmand or another machinist who is familiar with the tooling required to modify same..

  2. Billy Blankenship says:

    George i am looking for a 4 inch 6 grove 5/8 bore for a gen, can you help.

    • George B. says:

      most people run six rib belts on 8 vee pulleys just fine, bushings allow you to run near any size of shaft.. We have a 4.1 inch pulley.
      you’ll need order your own bushing at graingers or other source..

  3. Roger Barr says:

    I am retrofitting a detroit 2-71 to a ST 24kw generator head. I had a flywheel plate machined to a 48mm shaft with a keyway that matches the ST generator head. I was going to put a L225 lovejoy coupling between the two and run the detroit at 1800 rpm, but have decided to use a pulley system with serpentine belt instead. The ratio is 1:1.5 so I was looking for a match to your bushed pulleys. Can you help me? If you have other suggestions, I would welcome them as well.


    • George B. says:


      The ST24 has a massive rotor, If I were going to make up a belt drive, I’d consider a 3 Vee Common Back, and I’d look at an industrial supplier for same.. This combination is not on my radar as I’m focused on smaller gen sets. wish I could help, but I’m the wrong guy on this one..

  4. Derek Sharp says:

    Hello Mr. George,
    I hope I am writing in the correct place. I am having a problem with my oil press. It’s jamming on the copra becvause my changfa type 185 is running at a slower speed and is probably not getting all the force of the flywheel. If I go too fast the screw burns the copra. I would like to get more power but not turn the screw too fast and am running at about maybe half power.
    Can I put a different sized pulley on the engine so I can speed the engine and still have the screw turn at the speed I am comfortable with? Do you have anything like that in stock that would fit my purposes?
    I was just going to buy a 195 or greater but thought that maybe I could just change the size of the stock pulley.
    Does what I say make sense? I am rather new at this. Thank you.

    • George B. says:

      Derek, at this point, we need assume the oil press is set up right for the product you’re running, folks out there have tricks, adjusting the mositure content, ect. I’m no oil press guy, but there are those who drop in once in a while that are..

      Seems to me we need meet the torque requirements to press the oil, you can do that fast or slow, but you need the torque to get the job done. The 195 should be able to produce that torque at more RPM, and therefore press more oil.

      Here’s the delima you are likely using VEE belts right? More than one? you need make sure your engine pulley is not too small, some of the sites on the WEB can give you info on this, but some belts just don’t make that tight radius..

      You need research the smaller pulleys, or get a custom shaft for your engine that will take the pulley of your choice. I have stub shafts at 1.5 inch.. you’d need take it to a machine shop and have a boltabe base made.

  5. Derek Sharp says:

    I should mention that the engine would stop during the jams and I’d have a heck of a time back-spinning it to break it loose. Thanks.

  6. Derek Sharp says:

    Ok, Thanks for the response.
    Yes, there are definite tricks with the already pressed vs oil filled material and moisture. I’ve been trying it for a couple years off and on and I still learn everyday. Figured I would at least know something by now but it doesn’t appear to be the case!
    I believe you are correct= my feeling is also the torque. SOMETIMES if I don’t add TOO much dry and it wants to jam (actually the problem seems to be when the caked material inside wants to unjam and everything wants to excrude and once) the engine may almost conk out, but just barely the drop of life returns a beat at a time and the engine and press goes back to weather, full comfortable operating speed and the oil comes gushing out once more. But I’m not always lucky.
    I am using long v-belts, two, one probably more stretched than the other, though I do try to keep them fresh.
    After I wrote my question, I asked a good mechanical friend (good thing we have them) about the drive pulley. He replied that may get too small since the stock must be around 4 and half inch or so? Said I may do better if I get a larger pulley (now 14 inch or so)on the press maybe two more inches and speed up the engine for more torque since I’m only using maybe less than 3\4 of full speed on the 185. Maybe allow me more leeway if I screw up the mixture in the press.
    Sound reasonable before I start messing around in china? Thank you, you have a very useful, informative site. You have surely helped many a dunce.

    • George B. says:

      Derek, you might consider a common back belt, but you need make sure you have the correct belt for the pulley, and I’m not sure that people are running the right belts on theseset up.. orderign ‘matched’ belts can be a big help.

      It will be more money to address the problem on the oil press side, but maybe there’s some one out there who has a larger pulley that reads this? Another possivility is using a jack shaft in the middle and having several more common and less expensive pulleys there.. depends on waht a guy has in his scrap pile as to how he approaches the problem.

      All the Best,

  7. ken whitmore says:

    Hi George , ken here , it says you quit selling serpentine pulleys but drop a comment to see if you have some left. I need preferably a 4.75 that I can fit a 1 inch coupling in or maybe a 5 inch would do. Barring that I might order a 6.37 inch one and remount my 11.25 on the generator. thanks , ken

  8. les shepard says:

    l have a 7.1 hp lester petters diesel that was mounted on the back of a tank for stand by power it has a pulley that has a four bolt pattern mounted on the crank on the right flywheel on left.i am going to drive a gen 5 kw 38mm shaft1800 rpm with a serpentine set up if i can get the pulleys. bolt pattern is 1.24 -1.24- 1..14-1.35 bolt circle is1.75 do you know i cen get a pulley for the engine 2700rpm

    • George B. says:

      This engine is likely something like an air cooled AC1 or AC2 ?? Some of our UK readers might know more. The engine is likely rated at 3000, and you’ll need all the horsepower you can squeeze out to make an honest 3.5 KW with a little elevation and typical losses. I’d consider a five inch on the engine, and you’d need a stub shaft for the engine, or you could buy one and machine it, I have some blanks here.. might work.. always consider taper locks.. 38mm QD bushings are here..

      The ratio I’d consider is 5:8.4, check my work… email me at George@utterpower.com for more info..

  9. Randy B says:

    George, Do you have any more 4 inch pulleys (machined for an SK bushing)?
    Thanks, Randy B

  10. Mike Nash says:

    Hi George

    I have a solar off-grid site down here at the Bottom of the World in New Zealand

    I work with gensets as part of my job as an irrigation engineer & am increasingly dissatisfied with the way things have gotten cheap and disposable and how even the once-reputable brands are reduced to a sticker on the outside of a generic Chinese product

    So I started researching Listers

    I don’t want a 1500-2200 RPM “modern” one, I want an old 600 RPM 6/1 type.

    Are you still in business?

    I keep stumbling across your site but much of it seems old?

    I hope you are still going well; and congratulations on your adherence to Best Engineering Practice over expediency

    Regards, Mike

    PO Box 5392, Palmerston North 4414
    146 Fairs Road
    Palmerston North
    p 06 355 0009
    f 06 355 0029
    m 021 843 970
    w http://www.waterforce.co.nz

Leave a Reply