PMB Polyurethane Trailing Arm Bushings, Has anyone installed these? |
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PMB Polyurethane Trailing Arm Bushings, Has anyone installed these? |
jack20 |
Apr 9 2016, 10:57 AM
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#1
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Member Group: Members Posts: 406 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
I ordered and received a set of polyurethane bushings from PMB. They came without instructions. Prior to ordering Eric sent me a message advising me to "glue" the bushings into the shafts. He didn't specify what type of glue I should use. He also said that the bushings were already reamed to fit the shaft. My shafts will not slide into the bushings.
I've sent a couple of messages but haven't heard back yet and I'd like to tackle this today. Has anyone installed these bushings? What type of glue did you use? How tight should the shafts fit into the bushings? Supposedly the shaft is to "float" in the bushing but this doesn't seem possible. I don't have the capability of doing any precise reaming on these parts. I do know that once the install is complete a zerk needs to be installed at each bushing. Thanks in advance. Jack |
0396 |
Apr 9 2016, 11:05 AM
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#2
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Advanced Member Group: Members Posts: 2,046 Joined: 13-October 03 From: L.A. Calif Member No.: 1,245 Region Association: Southern California |
If it were me, I would drill out for the zerk fittings before you install the bushing. I would also measure the dia and take the bushings to a machine shop to turn them down.
This is my logical brain working. Good luck, your going to have fun with the installation. |
jack20 |
Apr 9 2016, 11:20 AM
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#3
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Member Group: Members Posts: 406 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Thanks. I agree that it would be easier to install the zerks prior to doing the bushing install but the hole for the zerk needs to go all the way through the bushing so the grease gets to the shaft.
I need to know how tight the shaft should fit inside the bushing and what type of glue is used for the bushing in the arm. I have a machine shop I could use to ream the bushings but supposedly these bushings are already reamed. If they're supposed to be a very tight fit I may need to press them in . I just need to know how much friction is to be expected. |
ThePaintedMan |
Apr 9 2016, 11:35 AM
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#4
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
Eric had posted a writeup here awhile back. It's really quite simple and well done. I believe he now recommends using a sanding drum, but I used the original approach with the brake cylinder hone.
Basically, you're going to hone each bushing to it's respective end of the pivot shaft. As Eric said, the bushing will heat up as you hone/sand it, so I swapped back and forth between bushings to allow them to cool down as I worked on the other one. As soon as you get a fair amount non-resistance in the shaft rotation, stop. It should rotate within the bushings with only hand pressure. At this point you, glue the bushings into the arm with JB weld. I chose to rough up the outside of the bushings with 100 grit first to provide a little extra surface area to keep it from rotating. Make sure you keep track of which side is which, and install the pivot shaft accordingly. If it still rotates fine with a little grease on it, then go ahead and mount the trailing arm temporarily without the pivot shaft. This will give you an idea of where the zerk fittings will go without being in the way. Remove it, mark it and drill those locations. Then install the pivot shaft and reinstall the trailing arm. Some folks also cut small grooves in the inside diameter of the bushing that intersect the zerk holes to help distribute the grease better. Sounds like a lot of work but should only take a couple hours. |
MikeM |
Apr 9 2016, 12:08 PM
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#5
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Senior Member Group: Members Posts: 564 Joined: 16-May 10 From: Calgary, Canada Member No.: 11,733 Region Association: Canada |
Be careful... I over honed mine and now they snap and pop as they move around.
I'm waiting for a new set right now!! |
914_teener |
Apr 9 2016, 01:31 PM
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#6
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914 Guru Group: Members Posts: 5,201 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
I have done them.
Search my user name. |
jack20 |
Apr 9 2016, 04:23 PM
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#7
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Member Group: Members Posts: 406 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Thanks George. I found Eric's write up. That and your update are exactly what I needed to feel confident with this project.
914_teener: thanks for the response. I couldn't find your thread but I did find Eric's write up while searching. Jack |
914_teener |
Apr 11 2016, 07:32 AM
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#8
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914 Guru Group: Members Posts: 5,201 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
Thanks George. I found Eric's write up. That and your update are exactly what I needed to feel confident with this project. 914_teener: thanks for the response. I couldn't find your thread but I did find Eric's write up while searching. Jack No problem... Make sure the pivot shaft is true to the bushing and isn't all rusted. I put a zerk on each side of the trailing arm and drilled through the bushing before installing the pivot shaft Also make sure that the bushing is shaved back enough so that the serrated portion of the pivot shaft engages the console mount. Check the mount to make sure it has not been ovaled over the years. Good luck. |
jack20 |
Apr 12 2016, 09:59 AM
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#9
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Member Group: Members Posts: 406 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Good tips, Teener. I was able to hone the bushings yesterday afternoon. I am able to rotate the shaft in each bushing with a fair amount of resistance. My hands are not as strong as they once were so I think I'll stop where I am. Don't want them too loose.
Should be able to drill and fit the zerks today, drop in the bearings and mount them up along with the new shocks. Jack |
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