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View Full Version : Clutch Pedal Linkage Repair



dthompson
12-29-2016, 11:54 PM
Recently I had a problem with my clutch pedal linkage popping off the pedal. I was able to snap the linkage back onto the pedal, but I could tell something did not feel right. Later I was able to dig into the problem a little more, and I found that the little plastic retainer was broken. I had another retainer lying around, but I decided to pull my pedal out and inspect things a little closer. I found that the post that the retainer snaps onto was worn on one side (the side that pushes the rod towards the clutch master cylinder).

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I decided that I did not want to install the other plastic retainer as the worn post would not properly support the retainer and it would eventually break again. My solution was to machine off the post and install a shoulder bolt instead. I cut most of the damaged area off with a hack saw and milled off the remainder using a mill we have at work. I then indicated the remaining boss and drilled a 0.257” (letter F) hole 0.600” deep for a 5/15-18 tapped hole. I then tapped the hole carefully to make sure it was straight. Tap the hole deep enough for 0.500” of thread length. I used a shoulder bolt from McMaster.com, item 91259A617 ($1.47 each). It’s an alloy steel (84,000psi shear strength), 3/8 diameter shoulder, 3/8 shoulder length, with a 5/16-18 thread. I also modified an oil impregnated bronze flanged sleeve bushing, item 6338K415 ($0.85 each), by reducing the length to 0.365”. I have access to a mill and lathe, so these modifications are easy, or you may be able to find an acceptable bushing elsewhere that will work. These bushings are great because they are not plastic, and they are self-lubricating. You may have to drill out the ID of your linkage to 0.500+. I used the ½ drill and just worked it a little to make the hole so the bushing would slip in (probably 0.505”). The only thing left is to reassemble everything. Make sure to test fit the bushing into the linkage and then insert the shoulder bolt to make sure everything moves freely. These types of bearings are generally true to the specification, but I have found some that were tight before and require reaming. Once everything is fitting and moving freely, reassemble for good. I placed the flanged side of the bushing towards the shoulder bolt head to prevent the linkage from rubbing against the head of the bolt. Also a little dab of blue locktite on the shoulder bolt threads will help keep it in place.
While I was at it, I made a new little plastic bushing for the clutch safety switch rod too. I just used some scrap Delrin we had laying around machined to fit.

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black V8
12-30-2016, 10:55 AM
Nice work, I just picked up the bushing since I noticed a bit of play in the pedal of my 90. Haven't taken it apart yet as I'm sorting through other issues. Thanks for posting your fix. Looks great.

good to doo
12-30-2016, 01:07 PM
Nice work there. I have noticed my clutch getting sloppy also.

89XR7TD
12-30-2016, 10:18 PM
That came out nice Derek!!!!

Sweet!!