Results 1 to 2 of 2

Thread: How to Replace the bearings in a Jet 1236 Lathe.

  1. #1

    How to Replace the bearings in a Jet 1236 Lathe.

    The noise coming from my lathe had gotten louder over the past 6 months. From checking various sites and posts I know that reeves drive lathes are not known for being as quite as a step pulley machine. But mine was so much louder now than when I had gotten it several years ago. Then the other day I chucked up a 11.5” by 5” piece of walnut to rough out. The noise got much worse until it just stopped turning. I immediately shut the motor off and tried to turn it back and forth by hand. It was locked up and wouldn’t turn anymore.
    I knew this day was coming but I had not been able to find what I needed as far as a good set of instructions as to what is required to replace the bearings. So I decided to document what I did and post it here, so that the next person will know how easy or hard it is to replace the bearing and get their lathe back in working order.

    General Disclaimer. I am by no means a formally trained repair technician, mechanic, or general know-it-all. I am posting the information on what I did and I accept no responsibility on how you repair your lathe.

    Because I did not know exactly how to remove each piece and in what order to do it in, it took much longer than it should have. Now having done it once and now knowing how to do it, I can disassemble everything down to the spindle in about 15 minutes or less. I know because I’ve taken it apart 4 times trying to fix something else which I will explain later.

    Go to the internet and search " Jet 1236 parts ", you should then be able to find several sites that has a parts manual and diagram that you can view and download.
    Remove the 4 screws that holds the cover plate over the reeves drive pulley. 1 top, 2 along the side, and 1 bottom back of plate.
    I immediately saw why my lathe locked up. Underneath the Reeves pulleys there is a small geared rod that is connected to the speed selector assemble. The locking bolt had come undone and the rod had moved forward and was now hitting along the edge of the pulley. This is why it locked up but not why it was noisy. I already had it in my mind that I was going to replace the bears so I went ahead with disassembling the lathe.

    Turn the lathe on and dial the speed down to its lowest setting. Now shut it off and unplug it. This will squeeze the spindle pulley closer together and you will be able to slip the belt off over the edge this way. Slide the belt to the outside edge of the pulley. Slowly rotate it until it rolls off the pulley. It will be tight between the edge of the pulley and the casting but with a little pulling and turning the pulley it will slip past this pinch point. Set the pulley aside.
    lathe pic1.jpg

    Using a pair of c-clip pliers, remove the clip from the end of the spindle shaft. Don’t worry about the other c-clips on the spindle, you will have easy access to them once the Reeves drive pulleys have been removed.

    Loosen or remove the 2 set screws that are on the outside pulley. Use a magic-marker or measure the distance from the end of the spindle to the edge of the pulley, so you can put it back in the same location.

    lathe pic2.jpg

    Now go back to the front of the lathe and remove the 2 screws that holds the speed reducer handle assembly to the front of the lathe. Pull out the whole rod and cover disk.
    If you’re lucky the entire reeves drive pulley assembly should now slide off the end of the spindle. I wasn’t that lucky. I popped off the other two c-clips and tried tapping the pulley and spindle from both ends for an hour and never got any were near being able to move the pulley assembly more than 1/8”. Do Not, Do Not, Do Not, take a hammer or screw driver and hit on the edge of the pulley. It is made of light weight cast aluminum and will easily crack or break off.

    Here is what I did to get the assembly the slid off.
    Use some fine sand paper to just clean up the end of the spindle. You’re not trying to remove any metal just clean up any residue and grit. Now for the secret, trick or whatever you want to call it. Put the speed control lever back in place but with the handle at the highest setting. Now rotate it to the lowest setting. This will push the assembly off the spindle. You may have to pull the speed lever out and rotate it to the highest speed setting again, but I was amazed at how easily it slide off.

    You now have easy access to the other c-clip on the spindle next to the bearing. Once this is off, use a wooden dowel rod and dead blow hammer, to drive the spindle towards the tail stock. My bearings stayed in place in the head stock housing. Insert a longer dowel rod through the center of one of the bearings and tap the opposite bearing out. You may have to angle the dowel rod up, down, right, left, to get the bearing to slide out. Once you have one of the bearings out tap out the other one.
    lathe pic3.jpg

    I replaced all three bearings in my lathe. If you are going to do the same then you will also need to remove the c-clip from the Shifting Lever bracket and tap that bearing out also. This bearing was more worn out on my lathe then the two spindle bearings. NOTE: It wasn't until after I had reinstalled everything that I found out that this was the cause for the increased noise in my lathe. The central pulley shaft had worn out and increased in diameter. This allowed it to wobble on the shaft as it turned. On the lowest speed setting it wasn't too bad , but when I increased the speed one or two notches the sound got worse. I went ahead and ordered a new set of pulleys from one of the many distributors online. Though the parts diagrams lists each side of the pulley separately, they are now sold as a set. Online you will see that the left side is no long available and is indicated with instructions to call.

    lathe pic4.jpg

    I took the bearings to a local gear/bearing supply shop. They were much cheaper than buying them online and I had them immediately. They matched it up to the identification number stamped on the bearing.

    Set the Shifting Lever bracket bearing to the side. It is a different diameter and thickness than the two spindle bearings. I sprayed the spindle with WD40 and then used some extra fine sandpaper or nylon woven cloth to just clean up the spindle. Wipe everything off so it is clean and dry. Then lightly apply or spray some white lithium grease on to the spindle. Take one of the spindle bearings and slip it over the long shaft of the spindle. I then set it bearing side down between the ways of the lathe and used a dowel rod and hammer to tap it down onto the spindle.

    lathe pic5.jpg

    Then apply or spray white lithium grease to both areas in the head stock were the bearings will go. Take the second spindle bearing and insert it in the rear head stock cavity. Use a larger wooden cylinder to tap it into place.

    lathe pic6.jpgThen slide the spindle with bearing installed through the front cavity and use a dowel rod and hammer to tap it into place. Put of course as I tapped the front bearing into place the rear bearing also moved and was not longer seated tight in the bearing housing.

    To be continued See part 2

  2. #2

    How to Replace the Bearings in a Jet 1236 Lathe Part 2

    lathe pic7.jpg

    It seemed that no matter how much I tapped the front and rear bearing the opposite end was going to be displaced by the same amount. So I had to immobilize one end while I tapped in the bearing from the other side. I used a large F style clamp to hold the front bearing & spindle in place while I tapped in the rear bearing. That worked perfectly. Afterwards I thought of another method that would be much easier. What I could have done was to bring up the tail stock and tightened it against the spindle. This would have prevented it from moving while tapping in the bearing from the rear.

    Install the c-clip that holds the bearing /spindle assembly together.

    lathe pic8.jpg

    As you can see the damaged done to the pulley in the photo below, the geared speed selector rod was no longer held in place by the set screw so it mover forward and began hitting the ribs of the pulley. To keep this from happening again during reassembly, I squeezed a small amount of Lock-Tite into the bolt hole for the set screw. Do not completely tighten the set yet, you will need to rotate the rod some when the Speed Selector pinion rod is installed. You just want it to engage the slot in the rod for now.

    lathe pic9.jpg

    Place the keyway back into the slot on the spindle. Align the slot cut out in the Speed Selector assembly with the keyway and slide it onto the spindle. Make sure that the top pin engages the spring and the bottom rod slides into the hole below.

    lathe pic10.jpg

    Now just slide on the other pulley position it from the end referencing the magic maker or measurement you took when you started disassembling everything. Install the c-clip, and don't forget to install the two set screws in this pulley.
    The two pulley half's should now be squeezed together and technically at its' lowest speed setting. Install the speed selector handle turned so that it engages at the lowest setting. This is where you may need to rotate the rod on the Speed Selector bracket if needed for the handle to slide in. Now you can finish tightening the set screw and nut on the Speed Selector bracket, but not too tight as the casting will easily strip out. Install the 2 set screws in the end pulley.

    Now just install the belt the same way it came off. I had to pull the belt tightly between the motor pulleys and used a screwdriver to get them to begin to spread open. I then slipped it over the edge of the opposite pulley and rotated them until it slipped on. Now plug it in and start it up just to check everything. Run the speed selector up and down. If everything checks out replace the cover and you are set for many more years of turning fun. And the thought of ever having to replace or repair something your lathe should not be that bad.

    lathe pic11.jpg

    As I mentioned in part 1; It wasn't until after I had reinstalled everything that I found out that the real cause for the increased noise in my lathe was because the inner pulley shaft that rides on the spindle had worn out and increased in diameter. This allowed it to wobble on the shaft as it turned. After installing a new set of pulleys, that loud iritating noise went away.

    One other thing that I discovered while I had the cover off was that the electrical wire from the motor going to the on/off switch had worn though both the outer sheathing and luckily only into the ground wire. Well in for a penny in for a pound, I replaced the electrical cord as well. Note to self, I'm going to do an annual inspection of all components from now on.

    lathe pic12.jpg

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts