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Posted by: Highland Dec 4 2018, 05:05 PM

So I'm at the stage where I'm going to drop the brakes and suspension to change bearings, bushings, calipers, rotors, pads, shocks, springs, etc. I plan to start with the rear then move to the front.

So the car will probably be off its wheels for some time while I'm trying to figure this all out.

I've emptied the brake reservoir with a turkey baster, but of course there's still fluid in the lines. I'm also thinking it would be easier to bleed the lines if there's fluid in them.

My question is where is the best place to disconnect the brake lines (before or after the flex) and what's the best way to cap it so I don't end up with brake fluid on my paint?

Posted by: mepstein Dec 4 2018, 06:16 PM

Clamp the flex line closed and remove it at the flex/hard line junction. Put the flex line in a bottle, unclamp and let drain. Replace flex line if you can’t remember the last time it was changed. Flex lines fail when they get old.

Posted by: jcd914 Dec 5 2018, 04:39 PM

I have a mix of plastic threaded plugs and ends of old brake lines that have been cut off and bent over a crimped. Both of these screw into the end of a flex line and seal it.

The plastic plugs came from packaged new brake parts over the years. Master cylinders used to come with plugs threaded into the line fitting to keep them sealed up in transit and storage.

The brake line ends were made up as needed.
I cut an old steel brake line about 1 1/2 inches long and left the flare nut on it.
Then I used vise grips and flatten about 3/4 inch of the tube at the cut end.
Then folded over the flatten tube about half way down the flattened section.
Then on the flat part of a vise (or anvil or other large hard metal), hammered the folded tube to insure it was sealed.

Jim

Posted by: BillC Dec 5 2018, 04:47 PM

Unbolt the hard line from the caliper and then put a vacuum cap over the end of the line. Quick, simple, and will keep it from dripping while you work on everything else.

However, Mark's guidance to replace the flex lines if they're old or you can't remember when (if) they were replaced, is very good advice.

Posted by: mepstein Dec 5 2018, 04:58 PM

The vacuum cap is new to me, I'll get some. I had to cut open the lines from a couple cars to get the techs at our shop to believe me that they go bad. They looked fine on the outside but were a mess on the inside. They are a bit of a pain to replace on the back but if you are doing everything, now's the time.

Posted by: rgalla9146 Dec 5 2018, 05:51 PM

A simple way to stop leakage when doing open brake line work is to push the brake pedal down about 3/4" and prop it securely in that position.
This will move the piston forward of the fluid inlet and prevent flow into the master
and out through the open line or lines. Caps or plugs are good insurance.
Old brake hoses fail invisibly. The failure is not usually described.
The hose swells closed internally preventing free movement of fluid. In both
directions. It can be necessary to cut the hose to release a stuck wheel cylinder or
caliper.
Removing rear hoses is simplified by cutting the hose off at the chassis end and using a deep socket and extension while holding the hard line fitting from turning with a fitting wrench.

Posted by: 914forme Dec 5 2018, 07:00 PM

If it is going to be setting a long time, I use old brake lines, cut them, crimp the ends flat a couple of times, and then clamp them in a vice, heat them up and run solder down the the line from the flare side.

You now have plugs to keep the everything nice and dry below.

If you don't know the age of the lines replace them. Also replace the fluid it absorbs water over time, which reduces its boiling point.

Posted by: BillC Dec 5 2018, 07:25 PM

Excellent point. Brake fluid in street cars should be flushed/replaced every two years (or less, but never longer). For race cars, brake fluid should be flushed much more often.

Posted by: Highland Dec 6 2018, 10:51 AM

Thanks for all the good ideas.

I was planning on replacing all the soft lines, but am I understanding the hard lines should also be replaced. Of course, I understand if there is any damage they should be replaced, but are they like the soft lines where they just wear out?

Posted by: ChrisFoley Dec 6 2018, 11:12 AM

You don't need to replace the hard lines unless one is kinked or badly rusted.

As suggested above, move the pedal to 3/4 depressed so no fluid flows. Then cut the rear hoses close to where they clamp to the chassis and use a deep socket to grip the hex end instead of fighting with a flare nut or open end wrench in that confined space.

Posted by: PlaysWithCars Dec 6 2018, 11:50 PM

This is what I usually do and it works great.

As an alternative I use a variation of this:
The objective is to stop fluid from running out of the fluid reservoir, through the master cylinder and out the open line. You can do this by disabling the vent in the fluid reservoir. On all 'newer' 914s the cap is the vent. If you take the cap off, put a single layer of saran wrap under it across the reservoir opening, and then reinstall the cap, you will only get a couple of drips out of the open line until there is enough vacuum in the reservoir to stop more fluid from running out. Just remember to remove it before you start bleeding the system. Or, you might spend a while scratching you head wondering what you did wrong when you can't bleed the system. Ahem... nothing to see here.

Posted by: 90quattrocoupe Dec 9 2018, 01:45 AM

Over the years of going to junkyards for the various VAG cars I own, I have picked up a lot of old flex brake lines. One end is female and the brake caliper end is male. I cut the lines, just about 1/2 inch from the fitting. Then I a take a screw, usually from the car I go them from, and run the screw run it up in the cut off hose.
Then I can use the female end on the male fittings, and male end on the caliper. Never leaks.

Greg W.

Posted by: cary Dec 9 2018, 09:21 AM

Ditto. With all the brake work I've done I have a life time supply. Took 20 to Rothsport to use there too. Leave them just long enough to crimp.