Clutch / Brake Pedal Pivot Bushing Repair Idea

[jwtaylor]

My clutch pedal pivot is severely worn and needs replacement.  The problem that I am having is that the bushings for the clutch and brake pedal are NLA from Nissan , or least I have not found any. 

My idea is to replace the metal bushings with a bushing machined out of Delrin or possibly Teflon .  It would be a one piece bushing drilled to 12MM for the pivot bolt and  the OD sized to be a press fit into the clutch pedal tube (about .75").  Any thoughts if this will work, would wear be a problem?  Any input would be appreciated.

 

Edited July 15, 2018 by jwtaylor
Edited bolt diameter to be correct.

[grannyknot]

The pin is still available, they just changed the p/n. The hole on the pedal that the pin goes through sometimes gets elongated from wear, in that case you can weld it up, fill it in then grind it flat and re drill. Not that Delrin isn't a good idea as a simple pivot but the constant stress of pressing the pedal might end up cracking the pin. Just the other day someone suggested in another thread of pressing in a roller bearing which I think would be the ultimate fix if not overkill.  

http://www.thezstore.com/page/TZS/PROD/21-2223

[Captain Obvious]

Here's that recent thread about the clutch pedal pivot pin:
https://www.classiczcars.com/forums/topic/60310-squeaky-clutch-pedal-and-clevis-pin/

 

[jwtaylor]

I was not clear enough in my description of the problem.  The hole for the pin that connects the pedal to the clutch master cylinder is worn only slightly.  I'm talking about the bushings that the clutch pedal itself pivots on at its upper end.  Where it is bolted into the pedal box.   See the 240Z fiche section 97 Items number 22, 24 for the clutch pedal and item 3 and 5 for the brake pedal.

[Patcon]

Why not just id the size and order some brass bushings online. as long as the ID and OD are close the length can be adjusted

[grannyknot]

6 hours ago, jwtaylor said:

I was not clear enough in my description of the problem.  The hole for the pin that connects the pedal to the clutch master cylinder is worn only slightly.  I'm talking about the bushings that the clutch pedal itself pivots on at its upper end.  Where it is bolted into the pedal box.   See the 240Z fiche section 97 Items number 22, 24 for the clutch pedal and item 3 and 5 for the brake pedal.

Now that I re read it you were very clear, that was me not thinking clearly.

[jwtaylor]

After looking at how the pedal pivots closer I think I need to replicate the original design.  The sleeve is pinched by the mounting bolt and the bushes provide the pivoting motion on the sleeve. 

[Captain Obvious]

2 hours ago, grannyknot said:

Now that I re read it you were very clear, that was me not thinking clearly.

And I was simply following his lead. I didn't even read your original post.    

[jwtaylor]

An update to this topic:

I just spent the evening looking for bushings that will work without having to machine them.  I have found some from asbbearingsonline.com that measure 15mm ID x 19mm OD and 16mm long.  These will work with the 12mm x 15mm stainless tubing I have to replace the sleeve with.  Should receive the bushings in a few days and will post results if they will work.

[jwtaylor]

I have had success on the rebuild of the clutch pedal pivot, and the brake pedal pivot by default as they use the same parts for the pivots.

I used ZM 1519-16  Powdered Metal Bronze Sleeve Bearing Metrics from American Sleeve Bearing  on line. I had to order 8 each to meet their minimum order amount.

"P/M bronze stock items are manufactured of pressed copper and tin powders and impregnated with lubricating oil. They are intended by design to be self lubricating, maintenance free and low cost.

Standard material specifications include: SAE 841, ASTMB 438 Grade 1 Type II, MIL-B-5687D Type 1 Grade 1, CuSn 6-6-3, Sint B 50

Standard impregnating oil conforms to SAE 30 specifications but product is also regularly supplied with special oils such as Mil-L-6085, Mil-L-17731."
 

I used 12mm ID x 15mm stainless steel tubing to make new sleeves, 45mm long each.  This tubing is not manufactured to a tight tolerance and  I had to ream the tubing out to 12mm ID to fit the bolt.  The OD of the tubing was also slightly to large to fit into the bearing by a couple of thousands.  Chucked the tubes in my wood lathe and reduced the OD to fit into the sleeve bearing with some emery paper testing the fit as I went.  The bronze sleeve bearings were an easy bench vise press into the pedal, the 16mm length is not a problem.

Edited August 17, 2018 by jwtaylor

[Captain Obvious]

@jwtaylor, I know it's unlikely, but do you have any pics of this process? 

I'm guessing if you had any, they would have been posted as part of this thread already, but couldn't hurt to ask.

[jwtaylor]

I did find a few pictures.  Not as many as I had hoped though.  I got a little lax about taking photos over the years. I still need to finish putting the car back together at this point.