Rear Wheel Cylinder. Leak

[Arfron]

I have changed all brake pipes and re-newed the rear wheel cylinders. ( I have used new copper washers on both cylinders . ) I purchased a new, rear cylinder from BullMotif + banjo and connector for banjo to cylinder, the old one had a crack in it .)
To date I have failed to make a fluid tight joint on the banjo washer area . I have checked the banjo , honed the faces , just in case of any grooves etc, but , to no avail !! Has anyone any suggestins, before I am foced to buy new parts and have another go ? I purchased a new/old stock cylinder for the passenger side .,and used the old banjo+new washers --no leaks to date ! Any help-greatly appreciated Arfron

[mowoggy]

Hi

Just a thought - is the brake pipe and connector both the same type?
(either single or double flare)

I've seen a car recently that leaked fluid, and found that the connector had been replaced with a single flare type.

Cheers

[Scott]

Arfron,
I can think of 3 other possibilities:
1. The thread/hole in the wheel cylinder is not deep enough & the connection bolt is bottoming out before compressing the copper washers.
2. The banjo is slightly thinner than the original & having the same affect as #1.
3. The thread is misaligned & skewing the connection bolt & not sealing the washers evenly.

It might pay to do some measurements of the new parts against your old parts.

[Arfron]

Many thanks for the suggestions -Mowoggyand Scott. The leaks only occur around the copper washers , so , I think that Scott's points may be a possibility . I assume , Mowoggy , that the leak which you came across, would have been where the pipe enters the banjo connecting bolt ? I don't have a leak at that point . I am not sure if this would have any affect upon the copper joint areas ?
Anyway, food for thought . Any more suggestions would be most welcome --especially if you have had the same problem . I can't be the only one in the world ,who has re-made these joints about five times , and with no success ????
Arfron

[57traveller]

If all else fails you could try annealing the copper washers by heating until cherry red then dunking immediately into cold water.

[thwaak]

I have come across a problem with copper washers fitted to a gas turbine, not fitted to a moggy I may add. Although the washers were brand new from the packet they would not seal gas tight as were too hard and would not compress. This may have been caused by age hardening whilst lying for years in the store. The washers were annealed and fitted gas tight.

[Arfron]

Many thanks for the suggestions 57Traveller + thwaak . I will be giving the new wahers the heat treatment tomorrow -- it's well worth a try . I suppose that BullMotif could have had stock, which is a bit elderly. The main supplier could have had the washers on the shelf for a few years -- who knows ??
Thanks again Regards Arfron

[rayofleamington]

If you have a gas hob then you can do it very easily, just holding the washer on a piece of long steel wire or thin nosed pliers. It takes a little while before the washer is glowing red/orange, but you'll be able to tell quite easily.
Then just drop into a cup of water.

[Arfron]

Thanks for the message rayofleamington. I couldn't do the heat treatment today -- domestic chores were a priority !!! Will try tomorrow . I will let you know how things develop. Relace washers/ pipe / bleed etc on Wednesday , with luck?!
Cheers Arfron