Asciidv Posted May 24, 2015 Share Posted May 24, 2015 Most British lorries of the 50s and 60's were fitted with tranverse brake cylinders at the rear. These are external to the brake drum and are therefore easy to remove if the seals have to be replaced. The cylinder pulls on a rod which has a wedge at the other end to expand the brake shoes. The same rod is extended and linked to the handbrake. The actual hydraulic piston acts on a coupling cylinder for the handbrake rod. The handbrake rod screws into the coupling cylinder. The coupling cylinder has to be prevented from rotating so there is a 'flat' in it and a pin runs through the casting of the cylinder which acts as the anti-rotation key. In this picture you can see the pin cutting through the inside wall of the cylinder. (The actual hydraulic part of the brake cylinder is below this). This picture shows the pin unscrewed. The pin will not pull out as it has two diameters. The end which does the 'keying' is a larger diameter than the shaft of the pin. So the question that I wanting to ask is HOW IS THE PIN ASSEMBLED and HOW DO YOU REMOVE IT? You may wonder why I would want to remove it. Well today after a brake re-build I was stupid. I gave the pin a little nip up during assembly which was a little too hard and sheared the hex head of the pin. I should be able to unscrew the remains out but of course only as far as is shown in the photo above. This shows the sheared off hex head which looks almost as if it is hollow to take the shaft of the pin, but how would the two be fastened together if this was the case? Any suggestions gratefully received. Thanks, Barry. Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted May 24, 2015 Share Posted May 24, 2015 Barry, I have changed cylinders on a Dennis years ago and recall they were Girlings, we found some for a Commer which were the right size. I do not remember that locking arrangement though. Looking at your photo, it is logical that the larger end of the dowel bolt should pass through the female thread, it is obviously made in one piece and can be the only explanation. Maybe there is a burr on the edge of the thread or bolt. regards, Richard Quote Link to comment Share on other sites More sharing options...
Caddy Posted May 25, 2015 Share Posted May 25, 2015 Could there be a sleeve or collar around the bolt that can be drawn or pulled out? Wonder if it was lightly pressed home by the bolt. Quote Link to comment Share on other sites More sharing options...
David Herbert Posted May 25, 2015 Share Posted May 25, 2015 Is it possible that the larger diameter round part that can be seen in the view looking down the cylinder bore, is actualy a roller that should be free to rotate on the small diameter of the retaining screw. It would still be an odd way to make it but there would be no other reasion to reduce the diameter of the retaining pin if the bigger diameter were part of it. The space that the bigger diameter part is in could have been cast into the cylinder as, if it is a roller, it would be located by the pin, not by the cavity. I suspect that the smaller diameter pin is supported either side of the cavity in close fitting holes and just won't come out of the one on the thread side of the cavity. These were a very common cylinder so it shouldn't be too hard to find a drawing, or parts if you need them. I have never taken one appart so would be interested in the final explanation. David Quote Link to comment Share on other sites More sharing options...
Sean N Posted May 25, 2015 Share Posted May 25, 2015 The two would not need to be fastened together. I can't recall how these are assembled - it's a long time since I've done one, most of the ones I do are Bedford which are assembled differently. However, is it possible that the parts are just corroded together? I think I have a couple of NOS cylinders, or instructions for same; if I do I'll have a look and see how they're assembled. Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted May 25, 2015 Share Posted May 25, 2015 I am sure this is a Girling transverse cylinder going by the boot. Never seen one with a locking arrangement like this, normally a stop screw which acts against a flat on the sliding member inside. Just dug out an old Girling catalogue from 1950's onward, lists Dennis, but none of the illustrations are like this. All the Lockheed cylinders of this type only have a stop screw inside to stop the inner member turning, so cannot offer anymore advice on this one. Quote Link to comment Share on other sites More sharing options...
Asciidv Posted June 9, 2015 Author Share Posted June 9, 2015 I ground off the remains of the thread and then drilled a shortened 5/16" UNF bolt to take the remains of the pin. This was silver soldered in place so all was as good as new. However a couple of weeks later a new cylinder arrived and all was revealed about how the pin was fixed in place. As you can see there is across drilling with what looks like a 3/64" pin inserted which prevents the larger diameter of the anti-rotation pin from moving past. The pin is obvious on this cylinder as the stake marks can clearly be seen. 60 years of rust seem to have obliterated these marks on the original cylinders - if they every existed! Finally, Sean, if you do have two spare transverse cylinders I would love to buy them off you. Perhaps you could drop me a PM if you can lay your hands on them. Best wishes, Barry. Quote Link to comment Share on other sites More sharing options...
Sean N Posted June 9, 2015 Share Posted June 9, 2015 Sorry Barry, having said I'd look to see how they were fitted I forgot all about it. Glad you got it sorted. I'll check what I have and get back to you. Quote Link to comment Share on other sites More sharing options...
Sean N Posted July 6, 2015 Share Posted July 6, 2015 Barry, I've finally remembered to have a look for those wheel cylinders. Sorry it's taken so long. I have found three, all Lockheed. I thought I had more, but they're obviously still buried. They are: 1 x AU/LK 16566 given on the box as for Thornycroft Nubian MkVa and fire fighter, though I think it'll fit other vehicles. Casting is marked Lockheed 44955 1 x No identification but externally appears identical to the above, casting is marked Lockheed 15052/2 1 x No identification, externally appears to be the same dimensions as the above but the opposite hand, casting is marked Lockheed 10??0-44-1C and mounting flange is stamped No.21 14955 / JHS They do not appear the same as yours (I think Richard is right in saying yours are Girling); they have not got the large lug that the locking pin is on, nor the other mushroom shaped lug, and the boot is much shorter. Quote Link to comment Share on other sites More sharing options...
Dodge 671 Posted March 19, 2019 Share Posted March 19, 2019 Hi all, joining the conversation to ask just how to remove a Lockheed transverse cylinder that connects to the expander through the brake backing plate. Mine is rusted together and for the life of me I can’t see how to get the cylinder off. It has the casting number 14955 as quoted above. Thanks in advance Anthony Quote Link to comment Share on other sites More sharing options...
Xtractif Posted April 4 Share Posted April 4 Hi what vehicle are these fitted to similar to. Bedford but connection point back? Quote Link to comment Share on other sites More sharing options...
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