Weeping Banjos

[Mac]

No, not a bluegrass song.
I'm putting the last bits together on the PS and front disc brake upgrade to my `63 C-10 Chevy. I can't get the banjo fittings to seal on the calipers. This was a kit (mid 70's Chevy C-10 components I think) so the calis and hoses are new. The copper gaskets looked a little suspect -like some oxidizing discoloration- so I went and bought new ones. I'm still just filling and gravity bleeding and I'm getting slight seepage, so it's gotta be worse in use and under pressure.
Any help?

[enjenjo]

You should have two copper washers on each banjo, one between the caliper and the banjo fitting, and one between the fitting and the bolt head. If you have it that way, I have found is some cases you need a thicker washer in there somewhere, as the bolts do not have enough threads to tighten up properly. At times I have used a third washer too, if I could not find a thicker one. Harbor Freight has a copper washer assortment for under $5 that should have what you need.

[Mac]

Yeah, I have a washer on each side of the hose end. The replacement ones I bought are a bit thicker than what came with the kit and there was some improvement; the joint were "running" at first.
I even gave some thought to annealing the washers to soften up the copper for better crush. Both the hose ends and the cali mating surface have anular ribs.
Not sure I understand about the bolts not having enough threads to tighten properly and how thicker or stacking a 3rd washer would help that.

[Fat Cat]

Yeah, I have a washer on each side of the hose end. The replacement ones I bought are a bit thicker than what came with the kit and there was some improvement; the joint were "running" at first.
I even gave some thought to annealing the washers to soften up the copper for better crush. Both the hose ends and the cali mating surface have anular ribs.
Not sure I understand about the bolts not having enough threads to tighten properly and how thicker or stacking a 3rd washer would help that.

If the threads on the bolt are bottoming out in the caliper before the washers are crushed then the chance of it leaking is greater.

[wayne petty]

i would also inspect the clamping surface...  on the caliper... make sure there are not any marks where calipers could have banged together in the core pile.. a dent across the sealing area will sure ruin your day...

trial fit the banjo bolt into the caliper without the banjo fitting.. see where it bottoms out ..?/

try it without the copper washers...   see if it bottoms out before it gets tight...

you can always grind a little off the end of the threads as fat cat was mentioning ..      cleaning afterwards.. of course... if it bottoms out before pinching the copper washers tight...

replacement banjo bolts are also available...   if over torqued.. the they will stretch... not a good thing...

got a thread pitch gauge?   can you check the threads for stretch???

Brake, Brake Hose Bolts
Brand:   Dorman - HELP! - Carded
Item Number 13935  
    GM 1978-71  passenger cars are shown in the listings.. no trucks..
Thread:   7/16"-20
Length:   7/8"
Hex:   7/16"
~~~~~~~~~~~~~~~~

just to show the thread size...
Brake Caliper - Front
For your 1973 Chevrolet Truck C10 1/2 ton P/U 2WD 5.7L 4BL 8cyl
Part Number:   C110
Notes:   Driver side
Inlet Size:    7/16-20 In.

[tomslik]

regular hose getting used with a "metric" caliper?
good luck sealing THAT....