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Posted by: swl Aug 4 2011, 08:48 AM

it seems like a dumb question but how do I know what master cylinder is on the car. Brakes are REALLY firm. Way too firm for my liking. I feel like I would need two feet for panic braking.

Posted by: dflesburg Aug 4 2011, 08:55 AM

they have a number cast into the side should be 17 19 or 2x I think

Posted by: Eric_Shea Aug 4 2011, 09:26 AM

With a mirror.

The number is cast on the top by the union where it bolts to the firewall.

Posted by: swl Aug 4 2011, 10:35 AM

of course it's on top! Why put it someplace where you can see it?

Car is off getting its safety done will have to wait until it gets home to have a peek.

Eric is there anything else that would add to pedal effort? Calipers are rebuilt. I haven't replaced the soft brake lines but that is next on the list. I don't suspect them though since the brakes are so rock hard - no spongyness. Pads are new but just stock - no fancy racing compounds.

Posted by: swl Aug 4 2011, 09:15 PM

can't see anything - cylinder is really badly corroded. My mechanic says it might improve a bit as the pads and disks scuff up so I'll give it a bit of work and then make the call. Probably will wind up pulling it out and cleaning it up. looks like there may have been (be some) leaking somewhere. Best to go in and look soon.

Posted by: Eric_Shea Aug 4 2011, 09:54 PM

Most people complain of just the opposite and, as the pads wear in, the pedal usually gets harder.

I would check out everything right now. Did you do anything recently? Rebuilt calipers? Try the pad bedding procedure on my site. Then go around and check every wheel/caliper. See if they're all the same temperature (careful, they could get very hot). While you're doing that, see if it pulls to one side or the other.

Your condition means you either have pressure building in the system or you have a larger 23mm MC. Could be an aftermarket MC that does not have the proper markings and is over-sized.

Posted by: swl Aug 5 2011, 06:07 AM

This is a new to me car Eric. Not on the road yet other than testing. DaveP rebuilt the calipers for me and I've installed new rotors. It is possible that I could have messed up the venting clearance on the rears so I'll have another check down there. I am concerned about the soft lines so they come next.

I like the theory that they are bigger than 19. The amount of corrosion fits with aftermarket. I should probably just bite the bullet and buy a new 17. Brake travel never bothered me back in the day so I really shouldn't be bothering myself with the 17/19 debate.

Today I'll do your bedding technique and then try locking up the brakes to see what the distribution is like. She is now safety certified and plated so I don't have to be watching over my shoulder for cops

Posted by: Eric_Shea Aug 5 2011, 07:18 AM

Posted by: swl Aug 6 2011, 04:59 PM

Took her for a bit of an extended drive today (been a LONG time ) but I only used the brakes normally. Although it improved greatly from the first set of stops there is enough bothering me that I don't want to stress them just yet. Going back up on the jackstands to get the softlines replaced, Since I've gone this far I might as well to the MC as well and have it new from stem to stern.

Been years in the making - another week or two to be safe is worth it. But damn I WANT TO DRIVE this sucker.

Posted by: swl Aug 21 2011, 09:48 AM

I have the soft line in hand now. Had the flare nuts soaking in PB laster for about 24 hours. I can only get one nut to break. I'm a bit paranoid about stripping them.

Is it ok to use heat on them? MAPS ok?

Right now I'm using a standard 11mm flare nut wrench that is pretty short. What is the concensus on using a crows foot and breaker bar? That would give the leverage I need but might be a quick way to stripping it.

Posted by: Racer Chris Aug 21 2011, 10:12 AM

Try tightening the fitting slightly before loosening it.
You might break any corrosion in the threads loose that way, thus making it easier to disassemble.

If you're going to replace the hoses anyway, you can cut them close to the fitting and you may be able to use a more effective wrench that way.

Posted by: swl Aug 27 2011, 01:03 PM

well I got it off without stripping the nut.

The threads not so much ...

A novel way to screw up.

Posted by: r_towle Aug 27 2011, 01:07 PM

Consider replacing the hard lines also at this point.
For the soft lines, cut then with wire cutters right up next to the fitting and use a 6 point deep socket to get them off.

Rich

Posted by: swl Aug 27 2011, 01:17 PM

but the nut that is giving me grief is the small one on the hard side.

new hard line is the only answer of course. Those threads won't hold anything. This is on the wheel side so it shouldn't be to bad.

Posted by: r_towle Aug 27 2011, 01:31 PM

If you make the decision, just replace the hard lines at the same time and then you will know the threads are good.
Again, cut them and use a socket....lots easier.

Rich

Posted by: swl Aug 27 2011, 01:55 PM

live and learn I guess. The amount of time I spent trying to save the hardlines is probably way more than I'll spend learning to form a hardline.

Posted by: 76-914 Aug 27 2011, 02:27 PM

I agree with Rich. F**k it, cut it, deep socket and if it even looks at me wrong I torch it.

Posted by: Vacca Rabite Aug 27 2011, 04:53 PM

replace the hardlines. its an afternoon job, and the piece of mind is worth it. I have never been able to part 30+ year old brake lines without the threads going. They may have never been removed before.

Zach

Posted by: swl Aug 28 2011, 07:35 AM

QUOTE(76-914 @ Aug 27 2011, 12:27 PM)

Posted by: McMark Aug 28 2011, 11:29 AM

Replace the hard lines.

I usually break those flare nuts free using... *GASP* ViceGrips. Gotta get them really tight the first time. Gotta bounce/surge by applying short bursts of pressure. I never simply push hard..harder..harder. The surging is the key. I've used this technique on TONS of brake lines and have never damaged a flare nut. There is absolutely a risk in using this technique, but if applied correctly, it works.

Posted by: Eric_Shea Aug 28 2011, 01:59 PM

You "need" to replace them at this point.

I always use a MAPP torch and a flare wrench at that union to get those apart. It usually spares what you just went through.

***WORD OF CAUTION THOUGH*** a MAPP torch can quickly "cherry" your lines. They are rather thin walled and they can glow red hot in a few seconds with a MAPP torch.

1. Don't try wrenching them apart until it cools a tad.
2. If you're planning on keeping the hardlines, WATCH THE LINE as you turn the 11mm male end. Very often the male end and the line have become rusted together (the torch helps here as well) and you will see the line "twist" as you turn the 11mm end. You might be able to get away with it if you catch a small twist before it busts loose but... I'd write that line off in the name of saving your life somewhere down the road (literally).

Posted by: swl Aug 28 2011, 03:18 PM

Thanks all. The hardlines are being replaced. Bending up the new ones. Quite an art to that particularly when there are changes in plane. Hand eye coordination was never my strong suit.

Mapp info noted Eric. I'll give that a go on the rears when the time comes. Won't waste much time with it though - if it won't go then I'll just take the hardlines with the soft. I did sense that "twist" you are talking about when I started one of the nuts but it popped almost immediately. It wouldn't take a lot of twist to weaken that line.

Posted by: Ductech Aug 31 2011, 01:51 PM

QUOTE(McMark @ Aug 28 2011, 10:29 AM)

Replace the hard lines.

I usually break those flare nuts free using... *GASP* ViceGrips. Gotta get them really tight the first time. Gotta bounce/surge by applying short bursts of pressure. I never simply push hard..harder..harder. The surging is the key. I've used this technique on TONS of brake lines and have never damaged a flare nut. There is absolutely a risk in using this technique, but if applied correctly, it works.

Posted by: swl Sep 10 2011, 11:01 AM

The front soft/hardline replacement was a real 'adventure'. Now it is time for the rears. It has been suggested that removing the softlines with the engine still in will be a PITA. Looking at it there certainly is not a lot of room when doing the inboard end. I don't want to spend hours messing around cursing only to decide the engine has to come out. The engine will be coming out at some point to put my 1911 into this chassis but that is quite a ways away.

So - who has done it with the engine in place? How did it go?

Posted by: trfrick Sep 10 2011, 11:36 AM

I did it with the engine in and it is deffinately the tougher way to go. If you can wait until you are going to pull the engine your life will be much easier.

Trying to fit the new hard lines back on the proportioning valve is the hardest part. To see how hard this will be try to loosen the hardline for the porpotioning valve first.

Posted by: Eric_Shea Sep 10 2011, 12:22 PM