I know this modification has been looked at before, but I think this is a slightly different take on it. We are all aware of the difficulty in accessing the master cylinder under the floor – so a remote reservoir makes for a practical change and one which I regard as an improvement over the original design.
As part of a complete rebuild, I have recently fitted the restored bulkhead to the chassis and it seemed like a good point at which to install the brake fluid reservoir. I chose a replica Girling tank with a vented lid and a 7/16” UNF 20 tpi outlet. I located it in the front right-hand corner of the battery box. Utilising one of the regulator screws, I attached the clamp to the side and fed a length of 1/4″ Cunifer tubing through a grommeted hole in the bottom of the box. There is still plenty of room for the battery, yet the tank is neatly accommodated in a place where the fluid level can be easily checked and also avoids the risk of any brake fluid spillage onto paintwork…
The outlet pipe is made up from what I had left over from a complete brake system overhaul and, being armoured, matches the existing pipework. It follows the route of the starter cable by exiting the foot ramp but it then falls away down behind the engine and eventually emerges under the floor where it joins the master cylinder. The pipe is held securely by several P clips which make use of the emerging gearbox cover screws. This means that no new holes have been needed!
Before flaring the ends of the feed pipe, I had to ensure that the conical nuts for the 7/16” fittings were slid on in and in the correct orientation. Getting the pipe to bend where I wanted it to go was the most difficult part of the operation and would have been much easier if I had done that part before fitting the bulkhead …but it is always easier with hindsight!
The one part of this modification that I had been nervous about was machining the lid of the rather expensive ‘bronze’ master cylinder. I eventually plucked up the courage and mounted the stainless- steel lid in the 3-jaw chuck of my vintage Drummond lathe. (3 1/2” centre height). Fortunately, the lid on this master cylinder is quite thick and proved entirely suitable. I mounted a 25/64” drill bit in the tailstock and using the centrally positioned vent hole as a pilot, fed it through the lid. I then tapped a 7/16” UNF thread into the hole.
Due to the lack of space under the floorboard, I was limited in my choice but in the end, I chose a standard 7/16” UNF banjo fitting. This works well as the pipe lines up almost perfectly and avoids an air lock. Having checked for leaks and bled the brakes I am happy that the installation is robust and to a fair standard.
I hope this has been of interest.
Ray White (TC10030)