Clutch slave cylinder pushrod

[gromit]

I just removed the slave cylinder from my IIa GS and the bore & piston are OK but the pushrod has badly rusted.

https://www.aulro.com/afvb/images/imported/2018/02/330.jpg (https://flic.kr/p/24h1ZEg)DSCN4656 (https://flic.kr/p/24h1ZEg) by Colin Radley (https://www.flickr.com/photos/152321353@N07/), on Flickr

A quick wire brush cleaned the rust & gunk but it's badly pitted. Probably OK but I thought I'd look for a replacement. UK price varies from 29GBP to 18GBP, local price $64 !! Must be made of Kryptonite or something equally as rare.

I'm guessing that the ball end is hardened, apart from that it isn't rocket science......is it ?
I saw a pushrod the other day made from a HT bolt, the head had been machined or ground to the rounded shape needed to mate with the piston. I need to check the thread and maybe see if a long HT bolt can be sourced.

Part number is 537601 and GI64674324 (Girling part number).

Any other ideas ?


Colin

[bee utey]

Considering what it's off i'd suggest it's 5/16"UNF, common on British engineered vehicles of the era.

[JDNSW]

Yes, it will be 5/16" UNF Grinding the head of an HT bolt to shape would be, to my way of thinking, quite a satisfactory way of doing it, and for the amount of use it is likely to get a normal bolt would be perfectly adequate. A check of the hardness with a file may indicate it is machineable, and if this is the case, cutting off a couple of inches at the piston end, threading it and then attaching it to an extension made from a bolt with the head cut off and threaded, joined by a threaded sleeve. This may be easier to do than to shape the head of a bolt. Since the only load on the shaft is compression, the threading is probably not even necessary, and the joining sleeve could be either shrunk on or use a high strength loctite.

John