Brake Banjo Bolt

Jeff M

Senior Member
I ran hydraulic brakes on an A coupe like a '39-'48, but I'm having a hard time getting the banjo bolt T to seal. With pressure on the system I get a very faint seeping around the bolt head side of the washer. And yes, I annealed the copper washers and tightened the bolt as much as it would go. I read on here that the original style crush washers had rings like the brass junction, is that true? Some of concentric rings on the reproduction brass junction seem to be of poor quality. I assume they should be void of nicks and deformed edges to get a proper seal. The bolt was an NOS Ford unit with the correct recessed taper.


Has anyone else had this issue? Any ideas?
 

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Ugh banjos can be problematic. Block could be bad or other. Including installation.


Not sure if Lacy is still selling parts. They do conversions but I'm sure they would sell you a few parts needed. Give them a ring.


http://www.earlyv8garage.net/


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Yes, I have had that problem on the brake system on my '40. Running DOT5 and just could not get the seep stopped. It was crazy. Tried several copper washers. I ended up using a nylon washer which solved the issue.
 
I put hydraulics in my brother's '32 and it still leaks. All new parts, washers from different sources. I like the idea of tinning the copper washer. I'm wondering if there's a reason "Aussie merc" recommends lead free.
 
some brake fluids over time will attack the lead and start leaking also lead free is slightly harder than solder containing lead so can stand higher pressures
 
If you leave one washer off can you still snug the bolt up. I remember having one bottom out and having to shorten it. Not sure if it was this application.

John
 
old trick tin the copper washer with lead free solder

Okay, now this advice I'm going to file away. Thanks for the tip. I've been fortunate for all of these past years - no leaks. But, who knows what the future holds. Thanks again.
 
If you leave one washer off can you still snug the bolt up. I remember having one bottom out and having to shorten it. Not sure if it was this application.

John


I'll give that a try when I blow it back apart, however I do remember four threads sticking out of the bolt with it through the block with a washer on each side, which should be correct. I'm starting to think it might just be a bad brass block, the concentric rings might be machined bad. I ordered two more from two different places to check out. The washer on the hose side of the block sealed fine.


Do you guys tap the head of the bolt as you tighten it or just snug it up tight? I've heard tapping it can help seat the crush washers as you tighten without just relying on thread torque.
 
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