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Help! Brake Lines Leaking at ABS Pump

Big T

Big T

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Location
Fullerton, CA
I know this is the wrong forum, but this is where the traffic is and I need (hopefully) immediate help as I'm off traveling first thing in the AM for two weeks and the wife needs the Suburban while I'm gone to move her mother into Assisted Living.

I recently changed out all the brake hard lines with the stainless kit from in-line tubes. The upper middle and outer lines are leaking at the ABS pump. I can see the drips when the brakes are pumped. My wife had the the Burb up at Big Bear and saw a pool of fluid under the driver's side. She had low brake pedal, but was able to make it down the mountain. This occurred while I was on the road working and she was up there while our home in Fullerton was being fumigated for termites.

When I installed the lines at the ABS pump, it was tough getting a seal. I finally did and the truck went a month and a half without leaks there, then the current event. I've pulled and re-installed the two lines and the outer one with the larger nut has stopped leaking, but the middle one with the smaller nut (goes to passenger side front brake) is still slowly dripping and I've tightened as far as I can.

Is the seal created by the flared end seating inside the pump? Or do I try to seal it up with teflon tape?

Unrelated, I had the passenger side front braided hose rub against the tire and wear through the hose. The braided stainless hoses do not come with a mounting bracket to attach them to the upper A-arm, which allowed the hose to rub against the tire and rim. In-line sent me another hose, but no suggestions as to how to prevent this from happening again.

I'm starting to wonder whether this supposed upgrade was more trouble than it was worth.
 
The lines seal via the taper of the lines seating against the taper inside the seat. As for the leak, make sure it is the seal for the line and not the o-ring for the proportioning valve going into the pump. I'm not sure though if the taper for the seat in the pump is a 37 or 45 degree taper though. Most steel lines are a 45 degree taper, but stainless is only a 37 as anymore will cause teh stainless to crack at the flare. As for the braided line, sounds like it's routed wrong or something. Mine have been on since 05 and don't have clips to atatch them to the a-arms and are as good now as they were when I put them on.
 
I bet you got the light duty 3/4 ton kit vs the 8600 GVWR kit.
You cut your old brake lines and remove and re-use the clamp. Or at least that is what I did when I discovered I had the wrong lines. So that didn't do me any good as I had the wrong lines for my 93.

The threads do not seal - teflon is useless. It will leak out the nut and line interface if the threads leak now.
 
THEFERMANATOR said:
The lines seal via the taper of the lines seating against the taper inside the seat. As for the leak, make sure it is the seal for the line and not the o-ring for the proportioning valve going into the pump. I'm not sure though if the taper for the seat in the pump is a 37 or 45 degree taper though. Most steel lines are a 45 degree taper, but stainless is only a 37 as anymore will cause teh stainless to crack at the flare. As for the braided line, sounds like it's routed wrong or something. Mine have been on since 05 and don't have clips to atatch them to the a-arms and are as good now as they were when I put them on.
Click to expand...

Proportining valve? That's singular and it's leaking in two places....two separate outgoing lines.

I suspected it's the facing of the flare not seating right. I'll call in-line tube on Tuesday.

The driver's side hose doesn't touch anything, but the passenger side did. I have a new one and might try zip tying it.
 
WarWagon said:
I bet you got the light duty 3/4 ton kit vs the 8600 GVWR kit.
You cut your old brake lines and remove and re-use the clamp. Or at least that is what I did when I discovered I had the wrong lines. So that didn't do me any good as I had the wrong lines for my 93.

The threads do not seal - teflon is useless. It will leak out the nut and line interface if the threads leak now.
Click to expand...

The OEM hoses are significantly fatter than the braided stainless, so the OEM clamps won't be of much use.

I told them exactly which model truck I had. Hard to imagine that they got it wrong. I'm thinking that the stainless did nit seat right initially and developed a crease that now prevents a seal. Stainless is much softer metal than what it threads into.
 
When I had one of my line crack, it was very difficult to find the stock line for the Suburban.
Initially, they gave me a line. When trying to install it, it was too short.
The computer parts inquiry software was tricky for this particular part because it did not show that the suburban needs the longer lines.
So, it has to be looked up using 3/4 ton diesel HD option.

The part store have to order it in, I ended up having the local hydraulic shop made it.

Moral of the story, yes, you can get the wrong parts, unfortunately.
 
These were from a custom kit by in line tube. It was a phone order. The lengths were more than fine as you have to cool the lines under the master cylinder to take up slack.
 
Could it be you cracked the flare when tightening the nut,or maybe the flare was offset and crooked to the tubing to start with(lousy quality control),that way it will not seal square to the nut.
If the line is long enough you might be able to cut the flare off and crimp a new one on with a flare tool.
These cheap double flare tool kits are basicly junk so it may not work on stainless tubing,i could not even get a decent flare with it on the harder stock tubing the other day when a brakeline started leaking on the wife's truck.
 
bison said:
Could it be you cracked the flare when tightening the nut,or maybe the flare was offset and crooked to the tubing to start with(lousy quality control),that way it will not seal square to the nut.
If the line is long enough you might be able to cut the flare off and crimp a new one on with a flare tool.
These cheap double flare tool kits are basicly junk so it may not work on stainless tubing,i could not even get a decent flare with it on the harder stock tubing the other day when a brakeline started leaking on the wife's truck.
Click to expand...


You don't double flare stainless for starters as it isn't malliable enough for it. The lines MUST be cut perfectly straight and need to be flared with the special 37 degree flare VS the standard 45.
 
Could be,i never used stainless, on second thought,if it is only a 37 degree flare,then it wont seal to well in a standard 45 degree fitting either IMO
 
THEFERMANATOR said:
You don't double flare stainless for starters as it isn't malliable enough for it. The lines MUST be cut perfectly straight and need to be flared with the special 37 degree flare VS the standard 45.
Click to expand...

Called In Line Tube tech support while in Denver Airport and it was a terrible connection. What I got was to use a deep socket to straighten the tube and then insert it and hold while finger tightening the nut. Tighten with wrench 1/2 turn, then back off and repeat 5x. Sounds like rebooting a computer as the fix all for Windows problems. He asked if I was near the truck? No, not for two weeks. I'm betting the lines are F'd up and have to be replaced.
 
Big T said:
Called In Line Tube tech support while in Denver Airport and it was a terrible connection. What I got was to use a deep socket to straighten the tube and then insert it and hold while finger tightening the nut. Tighten with wrench 1/2 turn, then back off and repeat 5x. Sounds like rebooting a computer as the fix all for Windows problems. He asked if I was near the truck? No, not for two weeks. I'm betting the lines are F'd up and have to be replaced.
Click to expand...


Basically what he is telling you to do is a way to fully seat the new line to the existing seat and make sure it is seated to each other. Also this will work to help match the 2 flares to each other better. Just be absolutely certain the connection is clean as any dirt or debris wil ldmage the flares and hurt any chance you have of it ever sealing.
 
bison said:
Could be,i never used stainless, on second thought,if it is only a 37 degree flare,then it wont seal to well in a standard 45 degree fitting either IMO
Click to expand...

You nailed it. I had problems getting a seal at the master cylinder and now at the ABS pump. You've probably identified the fatal flaw with the stainless hard lines.
 
When I flare stainless, I use a regular flare tool and heat the end of the tube up. It takes a couple of tries as the tubing cools before the flare is finished.
 
Finally talked to in-line tube's tech today and he said the flares were grooved or even cracked and I had to cut a reflare them. I ordered their flaring tool as I don't have the time to run around and find a place to get this done.
 
Well I used the "Bubble Flare" tool that In-Line Tube sent me and did two flares and still leaked. Since insanity is repeating the same thing over and expecting a different outcome, I pulled the fitting off the ABS pump and here's what it looks like inside:

1333862279.jpg


Looks like the seat is completely flattened out. Now I need to find a new fitting. This is becoming a PITA as work has me on the road for two weeks, then home a weekend. If the wife can't round up the fitting, then I'll hit a bone yard when I'm home next.
 
bison said:
I have an ABS pump laying in my shop,which fitting do you need?
I can drop it in the mail to ye
Click to expand...

Thank you so much. It's the middle line of the top row, 2nd from driver's side, has the smallest male side fitting of all the brake lines. I'll PM you with my information.
 
No go,..first fitting had perferct flare but buggered up treads.
second fitting had good treads but buggered up flare.
You go figger.:rolleyes5:
 
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