Rusty Hope Discs, leak problems.

[Bmartin]

I've been working with Charlie on an issue with the disc brake kit leaking.  The soft line is leaking where it attaches to the caliper.  I thought I would post up and see if anyone has had similar issues.  So far I have replaced the calipers (they seemed to be leaking from the bleeder threads as well and one caliper was sticking).  I bought the Chevy application banjo bolts which were a bit shorter to make sure I was not bottoming out.  And I've replaced the copper washers with new ones.  Both soft lines will not seal against the calipers.  I've attached a couple pictures to show what I'm working with.  Let me know if you have any ideas.  I keep hoping I'm doing something real obvious and I'm just missing it.

 

 

 

Difference in Banjo Bolts

Edited August 21, 2014 by Bmartin

[Dave72dt]

Any possibility the boot on the end of the hose is hitting on the caliper and tipping it a bit?

[Plymouthy Adams]

that is not just a problem with Charlies kit that is a parts problem from the supplier...anneal/soften the copper as some of the later ones are a bit hard copper..

[ptwothree]

Your pics look like you're using 2 washers on that caliper.....or maybe my eyes going bad.  Should be one washer per fitting.  If I'm wrong, then I would agree with the post by Mr. Adams.

[Niel Hoback]

One washer on each side of the banjo fitting. One seals to the bolt head, the other seals to the caliper.

[Bmartin]

that is not just a problem with Charlies kit that is a parts problem from the supplier...anneal/soften the copper as some of the later ones are a bit hard copper..

Interesting thought.  I can see the lines pressed into the copper from the fitting.  Not sure if that is any indication of softness.  I've been using the washers that came with the calipers. Let me look that up. 

[Plymouthy Adams]

I had a similar problem with a new set of crush rings myself not long ago..they stuff is not like it was..they thinner and a bit harder than the older style thicker and softer crush rings

 

If memory serves me correct..I tapped the bolt head lightly while tightening to compress the harder copper for a seal..tapped..do not slam bang

Edited August 21, 2014 by Plymouthy Adams

[Oldguy48]

I had a similar problem when I installed the disc brakes on my P15.  I tried different copper washers, and still had a leak.  I think the problem was with the rebuilt calipers, and the sealing surface for the banjo fitting.  I finally just kept tightening the banjo bolt until the leak stopped.  I'm sure its torqued far beyond recommendations, but I've had no problems since. Seems you cannot buy new calipers, just rebuilt ones.  And who knows what you are really getting.  Most likely calipers rebuilt by 8 year old starving Chinese kids. And my calipers were purchased at my local NAPA store. 

 

Wayne

Edited August 21, 2014 by Oldguy48

[Bmartin]

All my stuff has been purchased at NAPA.  I've had bad luck with NAPA for a while and prefer O'reillys.  But I went with Charlies recommendation.  In reality, they are all probably rebuilt by the same company.  I was actually tempted to go to the dealership and price all new parts, but it seemed everyone had good luck with the NAPA parts. 

 

The sealing surface of the caliper looks rough but flat.  The bleeder valve was stripped at one time because it has a helicoil in it.  and you can see the boss is a little bent.  Probably out of a wrecked vehicle. 

 

These are some good ideas, I'll give them a try tomorrow. 

Edited August 21, 2014 by Bmartin

[Dodgeb4ya]

Soften the copper washers. This issue has been common in the last 2-3 years. Chinese spec crappy weird copper washers. Bleeder screw leakage is another new common leakage problem.

 

Google search brings up a ton of these issues...http://board.moparts.org/ubbthreads/showflat.php?Number=6010889

Edited August 21, 2014 by Dodgeb4ya

[50 coupe]

Soften the copper washers. This issue has been common in the last 2-3 years. Chinese spec crappy weird copper washers. Bleeder screw leakage is another new common leakage problem.

 

Google search brings up a ton of these issues...http://board.moparts.org/ubbthreads/showflat.php?Number=6010889

 

How should you 'soften' the copper washers? Heat? Hit them with flame until they soot?

[Plymouthy Adams]

50 coupe, on 21 Aug 2014 - 07:03 AM, said:

How should you 'soften' the copper washers? Heat? Hit them with flame until they soot?

process is well defined on an internet search..not cutting you short, but typing the process could be lengthy..read a few article over there..get your thinking straight and confirmed

[50 coupe]

OK, I'll check it out.
Thanks

[Bmartin]

From what I have read, heat up the copper till it glows red, then toss it in some water.  I did not find whether you need a sooty flame or not. 

[Plymouthy Adams]

use a constantly moving blue flame..

[Bob S.]

You didn't say if you torqued them to specs. They have to be a lot tighter than you would think. I have tightened them to what I thought was tight and they leaked. Tighten to proper torque and no leaks. good luck , Bob.  You will have to look up the torque spec for year and model. sometimes the spec is hard to find but a factory manual will have it. I think this is why a lot of guys have trouble with leaks at the banjo fittings. 

Edited August 23, 2014 by Bob S.

[Bmartin]

I annealed the washers and then used Plymouthy's method of tapping on the bolt head and then tightening.  The leaks are now just a small seap instead of a drip.  So it looks like I'm heading down the correct path.  I bought some extra washers from NAPA but they were thinner.  Plus the caliper with the helicoil is leaking profusely from that bleeder.  I'm going to call a couple dealerships today and check the price and availability of a brand new Chebrolet caliper. 

 

 

You didn't say if you torqued them to specs. They have to be a lot tighter than you would think. I have tightened them to what I thought was tight and they leaked. Tighten to proper torque and no leaks. good luck , Bob.  

What is the proper torque spec from Chebrolet?

Edited August 22, 2014 by Bmartin

[Bmartin]

I went around to some different parts stores today.  Everyone's remans are made by Dorman except a completely loaded caliper w/brackets by Wagner.  I called the dealership and they are discontinued, so no new ones being made.  I swapped out my bad caliper at NAPA for one of my old ones.  I was only have minor leak problems with that one so I hope I have two decent calipers to work with.  I plan on tightening everything till it either stops leaking, strips or brakes at this point.  If that doesn't work, I'll pick up the Wagners and try again.  One of the parts guys mentioned that one of the hot rod brake manufactures may be having new ones made for their kits and to check around.  So I may look into that. 

[Dave72dt]

Why not have the NAPA store defect out the caliper you got and replace it with a  different one?

[Bmartin]

I've actually been through a bunch of calipers so far.  I think I've got the best I'm going to get from NAPA.

[Jeff Balazs]

You could try using 2 copper washers behind the banjo fitting. This solution works fine on my disc brake conversion. I had the same problem as you are having.

 

Jeff

[Plymouthy Adams]

many things could well affect the crush ring ability to seal..first is the new line banjo fitting the same thickness or slightly thinner thus saving overall cost on material..this combined with thinner copper rings and utilizing the same long bolts could easy prevent proper crush as the bolt could easily be bottoming out and not able to displace the correct pressure need to seal the unit..lot of little things could/can add up to a real problem..as for the leaking bleeder..the bleeder is tapered and makes the seal..not the threads..the threads are the mechanical incline plane that allow pressure to be displaced to the seating surface of the bleeder..a bent bleeder valve or one with a bottom surface that is distorted can prevent seal..be sure these are smoothly tapered..

[Dodgeb4ya]

There are a lot of poorly rebuilt calipers out there these days. Sad.

[Bmartin]

Just to update this, I did get all the leaks to go away on the front calipers.  I used the new washers from napa that were actually a little thinner and I used the chevy application banjo bolts instead of the ones called out in the install instruction since they are slightly shorter.  I tightened down the bolt, tapped with a hammer, and repeated until the leaks stopped.  I believe I'm somewhere in the 40+ ft/lb range for torque - alot.  For the bleeders, I just kept tightening them till they stopped leaking, again more torque than I believe should be required.  Post to follow with questions on pedal feel. 

[Bmartin]

I'll try posting in this topic to avoid forum clutter:

 

Disc Brake Pedal Feel:

 

I've got the Rusty Hope disc conversion on the front and stock drums in the rear.  I currently cannot find any more leaks in my system. I have a dual master cylinder with a single residual valve for the front (2lbs) and one for the rear (10lbs).  Both valves are Jegs brand.  I have bled the system using a pressure bleeder and am not getting any air out.  My brake pedal does not have the consistent travel I expected.  The first press goes about 1/2 to 3/4 through the pedal travel and feels a little soft, the next press has good feel and firmness, the third and later presses are a slight improvement over the 2nd.   If I hit the pedal again within a few minutes its stays pretty consistent.  If its sits for 5 minutes or so, it goes back to the longer travel.  I've tried adjusting the stock rears so the drums are locks and put the rear proportioning valve to full on.  I did see slight improvements.  When it sits over night is when I see the biggest increase of first press travel.

 

I was under the impression that with the residual valves, I would not experience this type of behavior, at least due to the fluid draining back to the master.  What are some of your experiences with this type of setup and what pedal feel did you have?  Are the residual valves supposed to be perfect or do they drain down over time?  Perhaps some other causes? 

 

The only other 'issue' I have is a mild sticking/dragging of the front calipers.  I have not driven on them yet and am expecting them to 'break in' once I do. They also release after a minute or two.