Crushable washers

[Richard Fritz]

Our MGs use flat copper washers in several places to control rather high hydraulic pressure, for example at the connections to the oil filter and at the ends of the flexible brake hoses. I have seen washers for this purpose described as "crushable" washers. My question is: can these be reused when reassembling connections, or should new washers be used each time? Richard Fritz, TC6649, Longmont Colorado USA [Non-text portions of this message have been removed]

[Chip Old]

On Fri, 18 Feb 2005 11:11 -0700, Richard Fritz wrote:

> Our MGs use flat copper washers in several places to control rather high > hydraulic pressure, for example at the connections to the oil filter and > at the ends of the flexible brake hoses. I have seen washers for this > purpose described as "crushable" washers. My question is: can these be > reused when reassembling connections, or should new washers be used each > time?

Copper is used because it is soft enough to conform well to irregularities in the mating parts. However it tends to work harden, so it's best to use new washers. If you can't do that, heat the old ones (a propane torch will do) and let them cool (don't quench) to anneal them. -- Chip Old 1948 M.G. TC TC6710 XPAG7430 NEMGTR #2271 Cub Hill, Maryland fold@bcpl.net

[Peter Roberts]

Depends on whether you want a leak.

----- Original Message ----- From: "Richard Fritz" RBFritz@comcast.net> To: mg-tabc@yahoogroups.com> Sent: Friday, February 18, 2005 1:11 PM Subject: [mg-tabc] Crushable washers > > Our MGs use flat copper washers in several places to control rather high > hydraulic pressure, for example at the connections to the oil filter and > at the ends of the flexible brake hoses. I have seen washers for this > purpose described as "crushable" washers. My question is: can these be > reused when reassembling connections, or should new washers be used each > time? > > Richard Fritz, TC6649, Longmont Colorado USA > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > >

[Chip Old]

On Fri, 18 Feb 2005 10:59 -0800, Terry Sanders wrote:

> But a "crushable" washer is a one time use only, is that not right?? > I've seen some copper washers that seem to have some abestos type > material embedded in them, what are these for and then there is a > crushable washer that has a U shaped, on its side, cross section. I > believe these to be one time use only. Joe Curto can supply you with > aluminum washers which seem to work better on the fuel system than do > copper washers.

The sandwich-type crushable washers are meant for one-time use, but I'm sure most of us have reused old ones from time to time. The plain flat copper type Richard asked about are best if used only once, but can usually be reused successfully if you anneal them. Flat aluminum washers also work well and can also be annealed if you need to reuse them. The problem with aluminum washers sandwiched between steel or iron parts is that electrolytic action tends to erode the aluminum. If you examine an aluminum washer that has been between two ferrous parts for a long time, you'll probably see a lot of surface pitting. That usually doesn't cause leakage during the washer's first use, but can cause problems if you try to reuse a pitted washer. -- Chip Old 1948 M.G. TC TC6710 XPAG7430 NEMGTR #2271 Cub Hill, Maryland fold@bcpl.net

[Richard Fritz]

Thanks for the advice. I will have another single-use item to stock up on. Richard Fritz

[joecurto@aol.com]

Roger you can use them again but the trick is to hang them on a wire and heat them cherry red with the propane torch and them quench in a bucket of water, they will be soft again. Though there is sort of a limit to how many times you can get away with this. Joe Curto [Non-text portions of this message have been removed]

[Skip Kelsey]

I will concour with Joe. I have been using this technique for over 50 years. Skip Kelsey..................................................... At 05:32 PM 2/18/2005 -0500, joecurto@aol.com wrote:

> Roger you can use them again but the trick is to hang them on a wire >and heat them cherry red with the propane torch and them quench in a >bucket of >water, they will be soft again. Though there is sort of a limit to how many >times you can get away with this. > >Joe Curto > > >[Non-text portions of this message have been removed] > > > > >Yahoo! Groups Links > > > >

[D&J Edgar]

Humm - we've had answers to quench the copper after heating in water and also to not quench. I have always air cooled. So I looked it up on the net and found this. Can the metallurgists verify? ========== In annealing of copper, the heating is the important part. The rate of cooling is immaterial. Whether you allow it to cool naturally or drop it into water makes no difference to the final softness. Traditionally, we drop it into water because that's what we were told, but it is not necessary. It's only a matter of convenience Try it both ways and see for yourself. JW Perth W.A. Oz ============ David Edgar, TC 5108 El Cajon, California

[Donald Wilkinson]

will concour with Joe. I have been using this technique for over 50 years. Skip Kelsey..................................................... digitaldon sez: WHEW! Thanks, Skip. Don TC 7993