Winter 2007- 2008


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Accelerator Shaft Bearings/Bushings - 3 Options

Hint...Hint....... I like Option 3 the best!

One of the more patience testing tasks to accomplish is the replacement of the two nylon bearings that hold the accelerator shaft in place in the bulkhead. A quick check at any car show will find that one or both of these bearings are missing. With my engine out, I figured it was the perfect opportunity to replace them both.............seeing as both on mine were missing.

Option 1 - Concurs Proper - but a Pain in the Butt

As part of a parts order from the fall I had the two bearings on hand. I soaked them in boiling water and then soaped them up and got about 1/4 of the first one. I figured I needed a thin bladed screwdriver to push the leading flange through but all that accomplished was to push the thin blade right through the flange. Ooops..........better try a thicker bladed screwdriver which worked just fine. The first one took about 10 minutes while the second one was done in about 2 minutes. Simple...easy..... now let's put the accelerator shaft back in............except it won't fit. There's not enough room to get it in the bearing without the interior kick panel blocking the way. So I figured I had two options: remove the kick panel to see if that freed up sufficient room or..........remove the driver side bearing, put the shaft through the hole, slide the bearing on the shaft and then try and fit it in the bulkhead hole. Now I know how hard that second choice would be...... they're hard enough to put in without the shaft in the way. I emailed the Triumph and 6-Pack Mail lists and got confirmation that my two options were the only two options. Someone did mention that the drivers side bearing must be installed from inside the car and not from the engine bay. I pulled that bearing out and upon examining it discovered that the opening is actually wider at one end and then tapers to the shaft diameter. If installed from inside the driver's side, the wider opening is available to accept the shaft. So did I re-install it? on.

Option 2 - Bronze Bearings & Locking Collar - OK but not the best option

When I asked my previous question to the Mail Lists, I got a number of responses suggesting the use of Bronze Bearings and Locking Collars. So I ordered some and immediately found a few problems:

  • a 3/8" shaft does not fit through a 3/8" bearing especially with the splines on the end of the shaft and/or if the shaft has been painted.
  • the bearing is too long and blocks the cotter pin hole on the end of the shaft in the passenger foot well.
  • a 3/8" locking collar doesn't easily fit over the splines or a painted shaft.
  • AND the bronze bearing and the locking collar scratch the heck out of a freshly painted shaft. I'll have to repaint my shaft once all the testing is done.

 Problem one is resolved with a Letter "W" drill which drills the 0.38" bushing to 0.386". An easy solution if you happen to have a Letter "W" drill............which luckily I have. I also have a drill press which made it "easier" but be careful as the bit size is so close to the hole size that it grabs the bearing and twists.

Problem two is that the bearing is too long and blocks the cotter pin hole where the shaft passes in to the passenger foot well.

Bushing is too long. No room for washer & cotter pin.
This is a safety issue for me.

For some people this may not be a big deal but to me it meant that if the locking collar should ever loosen up, the accelerator shaft could move out of the cotter pin to hold it in place. That's not a risk I want to take.

One other minor issue is that the bulkhead holes are probably out of round from having the shaft in there without a bearing to support it. If you try and hammer/tap a bronze bearing in place, chances are pretty good that you will crack it. This is easily resolved with a 5/8" grinding stone for your drill or Dremel. If I was doing this again, I'd get a stone that tapers from 1/2" at the tip to 5/8" at the back. That way, you can grind a little at a time and test for a nice tight press fit for the bearing. The one I used was 5/8" from tip to back.

Option 3 - Delrin Bearings & Locking Collar - made to order solution

I had just finished installing Art Lipp's Delrin steering column bushings and got to thinking about both his bushings and the Nylatron suspension bushings that Richard Good sells. They're both made out of a self lubricating, virtually indestructible plastic/nylon. What not make the shaft bearings out of the same material? I emailed Art with a picture of the bronze bearing along with all of the critical dimensions and a few days later I had a set to test fit.........along with an aluminum locking collar that he also made. Here's the advantages of his kit as I see it:

  • The kit is complete with bearings customized for driver and passenger side, aluminum locking collar and a Delrin washer for passenger side

  • The bearing hole is a perfect fit on the shaft. No need for any extra drilling.

  • The Delrin doesn't scratch the shaft paint.

  • Metal to Delrin has to be better then metal to metal from a friction standpoint.

  • Delrin is self lubricating.

  • The passenger side bearing is cut shorter to allow for the washer and cotter pin.

  • The driver side bearing is kept longer due to more stress on that side.

  • The locking collar hole is a perfect fit on the shaft. No need for any extra drilling.

All Installed
Driver Side Bulkhead with Locking Collar to keep it from moving to the right. Passenger Side Bulkhead - The Control Lever locks this side from moving left
Driver Foot Well. Extra length for support Passenger Foot Well with washer & cotter pin

Art has finalized his kit and sent me the following pictures. As you can see, this is as complete a set as you can get. No drilling or reaming of parts required!

Parts Clockwise: Grinding Wheel to round out bulkhead hole, Cotter Pin, Locking Collar,
Driver Side Delrin Bearing, Passenger Side Delrin Bearing & Delrin Washer
Driver Side has long bearing & locking collar

Passenger Side has short bearing to allow for
washer and cotter pin. Safety First!!

If you like what you see, drop Art an email for pricing and shipping information.