Banjo bolt torque

PostPost by: bloodknock » Sun Nov 04, 2018 11:06 am

Hello Folks
can anyone inform me of the correct torque for brake caliper banjo bolts please
Regards
Bob
I've got a deadline, at 73, I want to finish it before I die!
User avatar
bloodknock
Fourth Gear
Fourth Gear
 
Posts: 598
Joined: 04 Jun 2012

PostPost by: 661 » Sun Nov 04, 2018 11:38 am

Courtesy of Earl's

img_0447.jpg and


They are in the main for hose fittings but the information is transferable.
Graeme
S4 SE
S2 GTS
Caterham 420R
Sold - Peterson JPS Exige
User avatar
661
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1275
Joined: 29 Mar 2012

PostPost by: nmauduit » Sun Nov 04, 2018 2:07 pm

I do it by feel, as was said by others the mating surfaces should not be scratched otherwise sealing will be difficult.

I understand you're doing work on the car, not on the bench.

As to your question, unfortunately still without answering precisely as you wished, you risk more strippping threads with a brass banjo than with a steel banjo... if you feel it starts stripping, best to stop and change the banjo bolt, as if it strips completely chances are you may get metal shards in the master cylinder, or worse leave some of the thread inside, which will be a MC out job (not pleasant, just did that on my street car...). If the threads have been elongated you may forget it and risk even more to strip it the next time. With a new one make sure it does not bottom out before pressing the copper/aluminum washers. Last the total compressed area determines the amount of effort to deform the washers for a given pressure and material (a wider washer will require more torque than a skinny one - you may use that to cheat a bit, but of course if you go too narrow you'll fall into other problems). You can always check for flatness your copper/alloy washers by polishing them on 1000 grit or finer on a flat glass (don't overdo it or you'll risk creating a slant, polish them in figure eight and turning them regularly and homogeneously).

Also, there are aluminium washers that may be used to seal, they may be softer than the copper ones you're using hence sealing with less banjo bolt torque.

good luck !
S4SE 36/8198
User avatar
nmauduit
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2043
Joined: 02 Sep 2013

Total Online:

Users browsing this forum: No registered users and 13 guests