Front disc brake line install question

[mnagatani]

Ok gang, I need some help explaining how the brake fluid transfers from the hose side into this nut which then goes into the caliper. Am I doing this right? Thanks.



Mike

[Wes]

Well it is hard to say w/o the caliper in the picture. now the tab on the hose end normally lines up with some part of the caliper casting, to keep it from turning. The bolt commonly known as a "banjo bolt" needs a soft copper washer on both sides, preferable new ones. I have had success with old ones I try to put back in same place.

[DuckRyder]

If I understand your question correctly.

The bolt is hollow, the line will have a space to allow fluid to enter the hole and pass through the hollow bolt into the caliper.

[mnagatani]

Thanks for the reply. Maybe I'm missing something, but it seems that the "banjo bolt" has to be in perfect allignment for proper fluid transfer? Is there reason to be concerned for leakage if this bolt in not set correctly. I did a quick diagram of what I think is going on and I welcome any comments If Im not getting this!

Thanks

[ford4x4fun]

That looks right except I think there is a channel in there so it doesn't matter where the hole in the bolt lines up. As long is it is threaded correctly and tightened down. I could be completely off here, and this is completely my and someone will correct me soon enough if I am wrong

[DuckRyder]

Thanks for the reply. Maybe I'm missing something, but it seems that the "banjo bolt" has to be in perfect allignment for proper fluid transfer?

Two things:

1) the bolt need not be aligned, depending on the design of the hose, there is either a channel to allow fluid access to the full circumference, or enough slop in the bore to bolt fit to accomplish the same thing.

2) As wes said, you need a sealing washer on each side of the hose fitting.

HTH

[mnagatani]

DuckRyder, your explanation is making better sense now. I can see why now the copper washer/gasket is the key here. This site is going to save me from going insane!

[ford4x4fun]

DuckRyder, your explanation is making better sense now. I can see why now the copper washer/gasket is the key here. This site is going to save me from going insane!

and from running into a tree! Makes me wonder if my lines are on correctly, I don't have any washers I know because I have had lots of problems with my brakes and have been in them a lot. Things that make you say hmmm

[DuckRyder]

DuckRyder, your explanation is making better sense now. I can see why now the copper washer/gasket is the key here. This site is going to save me from going insane!

Yes, the copper washers are key, usually the flat surfaces have concentric rings to help seal when the soft washers compress.

Your drawing is correct except that you need a washer between the caliper and hose fitting because in actuality the white area that looks like an "H" laying on its side between your bolt and hose is going to be green (filled with fluid). If that makes sense?

In actuality the "H" area probably looks more like this "( )" or "{ }" to give the fluid more room and the washers a better seal. Edit: also note the reduced shank area of the hollow bolt where the hole is drilled...

Your square hose end is the same concept as this:



It is just that the square parts are usually used to stop rotation when tightening...

[mnagatani]

I updated the pic to make sense of what you are describing. Thanks again for that.

[DuckRyder]

That is about as close as you are likely to get in a 2 dimensional illustration!

You've obviously got the concept of how it works.