67 break rebuild - do it yourself or not?

[Richard M.]

Re: 67 break rebuild - do it yourself or not?

Tim, I got them with a complete PB brake package from Zip Products, DB-744. The package included 4 new rotors, Lonestar rebuilt O-ring calipers(very nice), USA hoses, lines, hardware, etc. It was the power brake upgrade kit. Correct PB booster, brackets, and I upgraded the kit to include the CSSB correct reproduction "DC" master cylinder. I also had to purchase new MC-to-front and MC-to-rear brake lines due to the re-located MC. Also replaced all other hard lines, and used DOT 5 fluid since everything was new.

The MC-to-rear brake line was a bit tricky getting in but worked out fine. Hardest part was the most forward clamp bolt under the footwell area. Trick is to use a thin wrench, then cut about 3/16" off of the bolt before you put it back in.

Rich

[Timothy B.]

Re: 67 break rebuild - do it yourself or not?

Rich,

I think I have one of those wrenches.

This year I intend to install power brakes on my 67 and I want to do it with the correct lines from the master cylinder, nice job..

[Domenic T.]

Re: 67 break rebuild - do it yourself or not?

After I painted and cut my rotors I checked the balance and was shocked as to how far off they can be especially a first cut that was basically a clean up to remove the paint.
I didn't see any indication that they were ever ballanced, no holes or machine marks, nothing.
I made special weights and screwed them in place where they couldn't be seen and also held in by the rotation of the rotor.
That is probably why it's good to ballance the tires on the car.
I wanted to know that when I rotated tires I wouldn't have to do the ballance over again on each.

DOM

[Gary R.]

Re: 67 break rebuild - do it yourself or not?

For runout I can tell you what I do, some won't like it, others may want to argue the point but I won't bother with that stuff.

As mentioned I'm rebuilding a set of T/A's off a '70 LT1 car now. These were never apart before. I just finished setting up the bearings to 0015 endplay. The original rotors have only 005 wear on them and I don't like turning rotors,(this is one the areas others disagree). I elected to clean up the surface with 100 grid D/A to get them glaze free. These rotors ran out 008-010 before I tore them down. I bolt them on( another area of discussion) and then check them. The LH rotor was out 010-012". I could have, but didn't, face the spindle,(another area). These were rough faced at the factory and are usually out 005-010" a lot of times, very common. Since I was reusing the rotors, I cleaned up the inside of the hats the best I could and around all the holes. Then I used SS shim stock to dial in the runout to 002",bolted on. That's pretty good, not as good as an on the car lathe but should be fine for lip seal calipers and certainly O-Rings calipers. This takes time to do and you have to have patience, it seldom dials in during the first couple of trys. Now there are some rebuilders out there that call their customers and tell them the spindles are bent they need a new one. I've never encountered a bent spindle unless the car was in an impact on the wheel. I won't mention the rebuilder because some get offended when I say these things,( yet another area of BS).

Bottom line the T/A's I just did have 0015" endplay and 002" rotor runout and all mating parts are machine fit. Works for me. If anyone goes to CF, there was a post there someone emailed me about a guy setting up rear bearings and his setup went from 001- 005 during installation. I don't know if that person is here but since I can't respond there anymore I will say I wouldn't use that setup at 005. There are a couple of reasons for this to happen, it's happened to me as well only I broke down the spindle, tossed out the new bearings and setup another set to get to my 0015-002 range.

Dom looks like you have a mill with a CNC retrofit there? The first Bridgeport CNC looked like that back when I came up rebuilding them 35 years ago.

[Timothy B.]

Re: 67 break rebuild - do it yourself or not?

Thanks Gary,

One more question, do you make the shim stock or can it be purchased?

Dom,

I wish the rotors on my car looked like that...

[Gary R.]

Re: 67 break rebuild - do it yourself or not?

I buy SS shim stock in kit form and punch them out. ENCO, MSC,etc will have it but they're about $80 a kit.

[Domenic T.]

Re: 67 break rebuild - do it yourself or not?

Gary,
I understand what you are doing and it has given me some short cuts on doing disc brakes.
By the way I have a roll of shim stock (aluminum)that is the thickness of tin foil that I have used for years, especially under some bearings that were a little loose after polishing a crank.
I will try the shim on my next set of discs that have to much run out.

Not to many understand that when these parts are mast produced they fall short of the measurements not to mention over heating during the machining process that causes warps when cooled. Thats where we come in and do it a little better.
I check all my rotable parts for balance and find a lot are not only out of balance but do not run true ( another probable cause).
I had to re balance a new harmonic balancer that was over drilled in the heavy area when they balanced it. A problem (I think) is that they do not re-test after drilling the balance holes.
This aircraft wheel balancer is good for wheels that are rated for over 250 MPH, it works as simple as it gets, the heavy spot settles at the bottom.
I have magnetized weights that I stick to the steel parts such as the one in the picture that lets me know how many grams to add.
This fly wheel and preasure plate were balanced seperatly and as a unit.
I only needed a few grams weight to balance them as a unit.

DOM

[Gary R.]

Re: 67 break rebuild - do it yourself or not?

Very nice Dom.

[Joseph U.]

Re: 67 break rebuild - do it yourself or not?

Is there any value or reason to flush all of the break fluid out of the system and reinstall new fluid?
thanks,
Joe

[Domenic T.]

Re: 67 break rebuild - do it yourself or not?

Is there any value or reason to flush all of the break fluid out of the system and reinstall new fluid?
thanks,
Joe

Joe,
The advantage would be to get the moisture out with DOT 3&4.
But if you pressure bleed you will mostly do that.

My bleed system works from the bottom up and I remove all the fluid from the MC and start bleeding. If you empty 2 times you will flush the system when fluid apears clear in MC.

DOM

[Joseph U.]

Re: 67 break rebuild - do it yourself or not?

Thanks Dom,
But I don't think I understand - are you pushing the fluid back from the wheel into the master cylinder? How do you do that? I have always bled the breaks by having the wife put pressure on while I "bleed" it starting with the right rear and working around to the left front till there is no air in the fluid coming out the wheel. Is there an easier way - maybe where I don't have to convince the wife that the car is still safe even though I did not pay a mechanic to do the work?
BTW - is there any way to tell if the fluid in the system is silicon v DOT 3 or 4?
The old posts are giving me a little scare>
Thanks,
Joe

[Domenic T.]

Re: 67 break rebuild - do it yourself or not?

Thanks Dom,
But I don't think I understand - are you pushing the fluid back from the wheel into the master cylinder? How do you do that? I have always bled the breaks by having the wife put pressure on while I "bleed" it starting with the right rear and working around to the left front till there is no air in the fluid coming out the wheel. Is there an easier way - maybe where I don't have to convince the wife that the car is still safe even though I did not pay a mechanic to do the work?
BTW - is there any way to tell if the fluid in the system is silicon v DOT 3 or 4?
The old posts are giving me a little scare>
Thanks,
Joe

Yes & yes,
Dot 5 is purple and your dot 3&4 will have a tint of amber which lets you know that moisture is present.
I do not have a sence of smell so I do a NO NO and put a pin head of fluid on my tongue when in doubt to see if I am dealing with DOT 3&4 if I am chasing a leak.

Second yes is avoid a divorce and get a pressure bleeder. I have a previous post on how to make a pressure bleeder and thats how I bleed from bottom up.

Some pressure bleeders bleed from top down but I have found that it is best to push the air bubble up rather than down and it doesn't take a special MC cap.
Your up now down method will work but takes MUCH longer with more mess and is less effective, but still works.

DOM

[Joseph U.]

Re: 67 break rebuild - do it yourself or not?

OK - I give up - what is the difference in taste between DOT 3/4 and DOT 5?
I will check the old posts on pressure bleeders.
Thanks,
Joe

[Domenic T.]

Re: 67 break rebuild - do it yourself or not?

OK - I give up - what is the difference in taste between DOT 3/4 and DOT 5?
I will check the old posts on pressure bleeders.
Thanks,
Joe

Joe, I knew I would get in trouble with the tast test.
I know what the taste is but you can taste new in the can to your old in the MC.
If it were dot 5 I think you would have noticed the color by now.

DOM

[Joseph U.]

Re: 67 break rebuild - do it yourself or not?

You got it,
the fluid is clear not purple - so DOT 3 or 4 it is.
Your system sounds great but may be a little beyond my construction skills.
Know anything about these "power break bleeders" that are advertised in Mid America or CC catalogs?
Maybe I should just do the breaks then take it to the "pro" and let them bleed it.
I need a set of tires anyway.
Joe