Removing poly bushings from trailing arms, JB welded in place |
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Removing poly bushings from trailing arms, JB welded in place |
jack20 |
Jun 27 2016, 11:45 AM
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#1
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
I need to remove and replace the poly bushings from my rear trailing arms. They are squeaking and popping and I can't stand it anymore.
The bushings are held in place with JB Weld. The arms are freshly powder coated and have new bearings in place so I don't want to use a torch to melt the JB Weld. Any suggestions on how to remove the bushings and clean up the inside diameter of the trailing arms without using a torch? Thanks in advance. Jack |
jmitro |
Jun 27 2016, 12:30 PM
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#2
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Senior Member Group: Members Posts: 713 Joined: 23-July 15 From: Oklahoma Member No.: 18,986 Region Association: None |
JB weld to hold bushings in place? (IMG:style_emoticons/default/WTF.gif)
cut off the end or drill them out with a hole saw then core out the remainder. the tolerances for bushing insertion is so small you almost need to take the trailing arms to a machine shop to make sure the mating surface is smooth enough for the new bushings to be pressed in |
stugray |
Jun 27 2016, 12:31 PM
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#3
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
I guess I would try to drive them out from the backside using a pipe and a hammer and see if you can get the JB weld to break?
Maybe filling the bushing with dry ice would make it brittle or crack it? I would take them to work and hose them with liquid nitrogen. |
jack20 |
Jun 27 2016, 01:00 PM
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#4
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
JB weld to hold bushings in place? (IMG:style_emoticons/default/WTF.gif) cut off the end or drill them out with a hole saw then core out the remainder. the tolerances for bushing insertion is so small you almost need to take the trailing arms to a machine shop to make sure the mating surface is smooth enough for the new bushings to be pressed in These are poly bushings and JB Weld is called for in the install instructions. The machine shop is certainly an option if I can't do this on my own. Thanks. |
jack20 |
Jun 27 2016, 01:02 PM
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#5
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
I guess I would try to drive them out from the backside using a pipe and a hammer and see if you can get the JB weld to break? Maybe filling the bushing with dry ice would make it brittle or crack it? I would take them to work and hose them with liquid nitrogen. I had considered using the freezer but not dry ice. Thanks. |
jmitro |
Jun 27 2016, 05:12 PM
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#6
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Senior Member Group: Members Posts: 713 Joined: 23-July 15 From: Oklahoma Member No.: 18,986 Region Association: None |
These are poly bushings and JB Weld is called for in the install instructions. The machine shop is certainly an option if I can't do this on my own. Thanks. that's interesting; I've never heard of that. Just for my own information, do you have a link for the vendor's instructions? Does the vendor recommend a torch for removal? |
rgalla9146 |
Jun 27 2016, 06:53 PM
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#7
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Advanced Member Group: Members Posts: 4,624 Joined: 23-November 05 From: Paramus NJ Member No.: 5,176 Region Association: None |
I need to remove and replace the poly bushings from my rear trailing arms. They are squeaking and popping and I can't stand it anymore. The bushings are held in place with JB Weld. The arms are freshly powder coated and have new bearings in place so I don't want to use a torch to melt the JB Weld. Any suggestions on how to remove the bushings and clean up the inside diameter of the trailing arms without using a torch? Thanks in advance. Jack Use a hacksaw blade to cut it into segments. Cut in the direction of the shaft. Buy a one end hacksaw blade handle. |
jack20 |
Jun 27 2016, 07:22 PM
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#8
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Thanks for the input, guys.
It's funny how these things go sometimes. I spent more time thinking about this project than it took to do it. It's 105 here today and I wasn't planning on spending time in the garage. After reading the feedback on my question I decided to go out and see what I could do. My garage is insulated so it was a comfortable 95 out there with the doors closed. (IMG:style_emoticons/default/sad.gif) In 3 hours I was able to pull the rear suspension AND knock the bushings out of the trailing arms on my bench. I'll feather out the JB Weld in prep for the new setup. I can't wait to get it back on the road w/o the cracking and popping. Thanks all! |
914forme |
Jun 27 2016, 07:31 PM
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#9
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Times a wastin', get wrenchin'! Group: Members Posts: 3,896 Joined: 24-July 04 From: Dayton, Ohio Member No.: 2,388 Region Association: None |
Pure Poly or Poly Bronze?
Polyurethane is a TPU( Thermoplastic) it is a heat set plastic, so heat except for extreme heat is out of the question. Now JB weld breaks its bonds at 600 degrees, but that will also burn off your powders so here are some ideas. Step Drill Milling Machine Really big drill bit Hack Saw Dremel with a carbide bit A round flapper wheel Liquid nitrogen the poly, hit it with a hammer Really long bar drive it out on a 20 ton press a finger nali file air powered body saw once you get them out you an use a brake hone or a drum sander to true them up. a file a (IMG:style_emoticons/default/smash.gif) and beat the (IMG:style_emoticons/default/stromberg.gif) of it A controlled (IMG:style_emoticons/default/sawzall-smiley.gif) cut Instead of a hack saw blade I would suggest a sawmill blade. drill 100s of tiny holes Purchase different arms Cold Chisel If it is pure poly a wood chisel would also work a ginsu knife, it cuts everything (IMG:style_emoticons/default/beer.gif) |
jack20 |
Jun 27 2016, 07:41 PM
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#10
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
[quote name='jmitro' date='Jun 27 2016, 04:12 PM' post='2364729']
[quote name='jack20' post='2364642' date='Jun 27 2016, 02:00 PM'] These are poly bushings and JB Weld is called for in the install instructions. The machine shop is certainly an option if I can't do this on my own. Thanks. [/quote] that's interesting; I've never heard of that. Just for my own information, do you have a link for the vendor's instructions? Does the vendor recommend a torch for removal? [/quote PM me and I will give you the info. Jack |
Eric_Shea |
Jun 28 2016, 03:21 PM
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#11
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PMB Performance Group: Admin Posts: 19,289 Joined: 3-September 03 From: Salt Lake City, UT Member No.: 1,110 Region Association: Rocky Mountains |
Heat with a torch.
JB Weld becomes malleable again at 500 degrees. |
76-914 |
Jun 28 2016, 04:51 PM
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#12
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,611 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
I can't wait to get it back on the road w/o the cracking and popping. Thanks all! I hear ya. Removing those "snap, crackle & popping" Rice Crispy bushings is on my list, as well. When I pulled out of my drive for the first drive I almost shit in my shoes when they barked at me. (IMG:style_emoticons/default/mad.gif) |
mark04usa |
Jun 28 2016, 09:58 PM
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#13
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'70 1.7 Tangerine Group: Members Posts: 351 Joined: 14-September 09 From: Austin TX Member No.: 10,805 Region Association: Southwest Region |
I skipped installing a set of poly bushings, left the originals in place. The 46 year old bushings are worn out, but, given the alternatives we have available, there is not a reasonable way yet to replace them. Please do keep us posted on your rear suspension bushing solution (IMG:style_emoticons/default/beer3.gif)
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mgp4591 |
Jun 28 2016, 10:18 PM
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#14
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914 Guru Group: Members Posts: 5,457 Joined: 1-August 12 From: Salt Lake City Ut Member No.: 14,748 Region Association: Intermountain Region |
Maybe a silly question, but did you install grease zerks to lube the bushings so noise would be minimal or absent? I was advised by another on this thread that this was the solution and the poly bushings would keep things crisp out back...
But you've already done the deed so this point is moot. (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif) |
jack20 |
Jun 28 2016, 11:34 PM
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#15
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Yes. I installed the zerks and when I pulled everything out the bushings were well lubed. Didn't matter.
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jack20 |
Jun 28 2016, 11:40 PM
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#16
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
In hindsight, I probably would have been better off leaving the old bushings in place.
I'm going to be installing the Elephant PolyBronze as soon as they arrive. I have the Elephant Rubber bushings up front. |
mgp4591 |
Jun 29 2016, 05:07 AM
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#17
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914 Guru Group: Members Posts: 5,457 Joined: 1-August 12 From: Salt Lake City Ut Member No.: 14,748 Region Association: Intermountain Region |
Sounds like you had everything covered so far as lubrication. I was thinking about making some light grooves in the surfaces of the bushing where the shaft fits, giving the grease a place to travel to and stay. I'll consult with an expert to see if that would destroy the surface causing them to crack prematurely or actually work similar to bronze bushings.
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914forme |
Jun 29 2016, 09:05 AM
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#18
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Times a wastin', get wrenchin'! Group: Members Posts: 3,896 Joined: 24-July 04 From: Dayton, Ohio Member No.: 2,388 Region Association: None |
In hindsight, I probably would have been better off leaving the old bushings in place. I'm going to be installing the Elephant PolyBronze as soon as they arrive. I have the Elephant Rubber bushings up front. So how did you get them out? Poly Bronze is a fine bushing, if installed correctly you will have a minimal friction bearing. Just make sure you have something under the arm when you install or remove the arm. Broke a grease zerk when I let one rotate down. (IMG:style_emoticons/default/headbang.gif) That made a simple task much longer. Worst thing is I have done it several times. (IMG:style_emoticons/default/blink.gif) |
jack20 |
Jun 29 2016, 12:17 PM
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#19
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Member Group: Members Posts: 412 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
I used a 16" long 1/2" drive extension and a BFH. 5-6 blows knocked them out.
I've become pretty proficient at mounting and dismounting the trailing arms. No broken zerks...yet. |
914forme |
Jun 29 2016, 12:42 PM
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#20
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Times a wastin', get wrenchin'! Group: Members Posts: 3,896 Joined: 24-July 04 From: Dayton, Ohio Member No.: 2,388 Region Association: None |
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