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Re-sleeve front brake cylinders?


WayneC

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Good point, Gunslinger... according to their price list, for about $650 + shipping you get calipers, rotors, pads and hoses; and if I'm interpreting the installation instructions properly, the only parts you need supply are some grease seals, and you must machine a tab off the supplied GM calipers (wonder why Turner doesn't do that step, and supply the seals with the kit?).

New XKS stainless brake cylinders alone would run $600.

Don't know the price for re-sleeving my originals.

It's not an immediate need, I recently installed a set of new wheel cylinders and flex hoses I had in my parts stash and I was thinking about having the old wheel cylinders re-sleeved.

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Actually, I'm having a weird issue with the brakes (the car has been sitting for several years)... probably too complicated to go into here, but after replacing the front pads and a leaking master cylinder, I had difficulty bleeding the brakes (both pedal-pump method and MityVac) so I had the car towed to a brake shop. I supplied them with all the parts I had in my stash, and they installed a (second) rebuilt master cylinder, new rear shoes, and new front cylinders... pretty much everything!

When I picked up the car they said that the rear brakes were squeaking and that the brakes didn't feel quite right but that I should drive the car for awhile to see if it would "wear in". It didn't, and in fact braking was so weak it felt to me like only the rears were working. I had to leave on an extended trip and didn't get the car back to the shop. On my return months later, I tried again to bleed the front brakes, but was unsuccessful bleeding the right front; I even tried bleeding the line before the flexible hose, using the MityVac, and that didn't work (never got solid fluid). So apparently I have a problem upstream, somewhere between the master cylinder and the flex hose.

Since I don't seem to have a fluid leak (the M/C stays full), and since the car doesn't pull to the left when braking, I am baffled.

I now don't trust the shop, their expertise seems to be just replacing parts, so I haven't had the car transported back to them.

I have very little knowledge about how a proportioning valve works.

Descriptions of proportioning valves seem to tell you what they do, but not how they do it.

Since I don't seem to have a fluid leak, is it possible the proportioning valve is simply not directing any pressure to the front brakes? Didn't see a warning light, but the light could be non-op.

That still may not explain why I can bleed the left front, but not the right front.

Possibly an air leak in the hard line to the right brake that doesn't affect the left brake?

...But then, why wouldn't I get a profuse fluid leak when pressing the brake pedal?

Hard to see much with the car parked on my sloped driveway, I assume there is a splitter in the front brake line between the proportioning valve and the brakes, I just don't know where it is.

Edited by WayneC
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A couple of items come to mind that can cause issues like you describe...

Todays brake linings are not what they were when your car was built. They used to have asbestos in brake linings which is now no longer allowed for obvious health reasons. Linings used today may or may not give braking equivalent to what was expected then. Also...some brake relining shops are better than others or use better quality lining than others.

While this is a general statement...not always true...soft brake linings give good performance and are quiet but don't have long life. Harder linings last longer, may not grab as well and can be ungodly noisy. As I said...all brake linings are not created equal. I don't know what year your Avanti is but in 1971 the rear brake changed to a GM brake shoe rather than the original shoes Studebaker used. Most brake relining shops are not going to waste time and money putting the best quality linings on such an obsolete application. If you walk into a shop and specify what you want with your brake shoes you'll likely come out better.

The difficulty in properly bleeding the brakes could possibly be from another source...what type of brake fluid are you using? In 1970 Avanti Motors began using silicone brake fluid (now called DOT 5), and it is in no way compatible with DOT 3 or 4. It will create a cloudy, milky mess if mixed together. Even if you flush the system completely and install DOT 5, it's notoriously difficult to completely bleed the air out of the system. Just something to look into.

Another possibility is not being able to bleed the air out of one caliper...sometimes a caliper seal is bad or the cylinder is scored and allows air to be sucked in and it won't leak fluid out. That happened to me with a Corvette. Until that was found I was never able to keep air out of the system...I'd drive it and suddenly the light would illuminate and I'd lose brake pedal. Once I almost lost all braking but was able to let it coast down with enough brake pressure for the final stop. Then I called for the flatbed.

Your car should have two blocks in the brake line...a distribution block which splits brake fluid to front and rear. You also have a proportioning valve which directs more fluid to the front than rear brakes since the front does most of the braking load. It's fixed, not adjustable so if there's a problem there it would have to be a clog in the line somewhere.

Does your car seem like the power brakes don't work and take too long to stop the car? You might have a bad booster. There are two ways to test that...

1) with the engine running pull the large vacuum hose off the booster. If the engine rpm's don't change, you have a vacuum leak inside the booster...if the rpm's increase, you have no vacuum leak in the booster.

2) with the engine off, press down hard on the brake pedal. While holding the pedal down start the engine. If the pedal drops down further, the booster is ok. If the pedal stays the same without dropping, the booster is bad. That's how I determined my car had a bad booster...the brakes were taking too much distance to stop the car with everything else in the system was new.

If you do decide to go with the Turner system, if it no longer comes with the grease seals (it did when I bought it), they're easily available locally. Jim Turner can probably provide them if you ask for them extra. I don't remember the application but they're Ford rotors so probably Ford seals.

Sorry to make this long, but diagnosing brake issues on an obsolete car can be tricky. Some of this I know from personal experience with a '63 Avanti I used to own and the '70 I have now. Experience is what you get when you don't get what you want. I gotten a lot of experience with my Avantis over the years...and advice from members here and vendors like Jon Myer and Dan Booth. I owe them a lot of kudos and don't mind saying so.

Edited by Gunslinger
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Appreciate your thoughts, Gunslinger.

I've owned and worked on five different Avanti's since the mid-70's. I've owned this Avanti since about 1979. I converted all of them to silicone fluid, bleeding never was a problem, nor was it on this Avanti until now. Like I said, the car sat for quite a while, and when I started getting it roadworthy again the M/C was empty, so I put in a rebuilt one (and the shop I took it to later changed-out my "new" one for a second rebuilt M/C, thus my concern over their competency). But I had trouble bleeding the right front brake, which is why I ended up having it transported it to a brake shop. I spent several long bleeding sessions over the course of a week (using manual pedal-pump AND MityVac, wore my hand muscles out squeezing the MityVac) before I gave up on it. Considering that after I got it back from the shop and found it still braked very poorly, and that I couldn't bleed it at the line end upstream of the right flex hose, and that I'm not losing fluid or seeing bubbles in the M/C reservoir, I don't think I can blame the RF cylinders or the booster for the bubbles.

I'm aware of inferior brake pad issues, I've had them, so I generally buy pads from Nostalgic. But brake pads have nothing to do with my not getting a hard pedal or my inability to bleed the right front. If the booster were leaking air into the brake system somehow, I would expect the bleeding issue to show up in the left front first (not the right), and I'd also expect the reservoir fluid level to go down. I consider the inability to bleed to be a key symptom.

I will check the booster... that's a possibility I hadn't explored.... but I never did get a good high, hard pedal, which I blamed on my inability to properly bleed the front right brake. Just trying to figure out why I can't get it bled properly. Booster shouldn't enter into that... I don't seem to be losing fluid, nor am I seeing bubbles in the M/C reservoir. Last issue I had with a booster was on this car, and it manifested itself in a high pedal with the front brakes being partially applied all the time; a booster rebuild solved that. I could just get the booster rebuilt again, but I think that's just throwing parts at the problem rather than solving it.

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I don't have any real answer for your problems, but as for re-sleeving your cylinders, I've kept these guys in my bookmarks in case I ever decided I needed them: http://www.hyedracyl.com/hdcadvnt.html

They reproduce our front disc cylinders out of stainless. Probably the ultimate fix for any problems up there! Price isn't that bad considering. I know Gary Johnson at AvantiNW has his re-sleeved somewhere around here. He has a bunch of them sitting on his shelf. I can try to get a hold of him or give you contact info if needed.

I just went through a problem with my rear brakes that were locking up on semi hard braking recently. I thought it was my proportioning valve that was at he culprit (in the distribution block) but decided to look into the easy stuff first. My rear brakes looked pretty new, but I had a suspicion that the brake cylinders were possibly wrong so I replaced them with correct parts only to find that they were the right ones (long story, but I doubted the abilities of the PO). I changed the springs since they seemed a bit worn but still had the same problem. I installed an adjustable proportioning valve I had sitting around and thought that would do it for sure!

Still had the same exact problem even with the valve turned all the way down. Frustrated, I changed the rear brake shoes (which appeared like new) and fixed the problem completely!

I still don't understand; they didn't seem to be contaminated and I had cleaned them with brake cleaner and even sanded off any glaze. Perhaps they were just the wrong compound?

On another note, I had a 67 Mustang with the 4 piston Kelsey Hayes fixed calipers. They are notorious for seizing up after sitting for too long in one position. Mine had the exact same problem you describe, I thought I was going to rear end somebody! New calipers and instant braking. I'm not sure if that problem applies to our Bendix calipers, though.

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No one has addressed the booster push rod adjustment. There is a procedure in the shop manual that cover this very specifically. If the master cylinder was changed, you may have a deeper bore in the actuating piston. It has to travel far enough to actually push fluid!

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Warren, I looked at the Hyedracyl website, and it appears the 2 1/8" SS wheel cylinders are priced at $240 each... that's $85 more than the XKS wheel cylinders!

http://xks.com/i-6916970-gr-64932067ss-wheel-cylinder-2-1-8-stainless-steel.html

http://www.hyedracyl.com/etype.html

On your rear brake shoes... is it possible they had been installed in reverse (front shoe where rear shoe should be)?

As for front cylinders seizing... I first used my originals, which showed no sign of leakage, but then the brake shop put in the brand new set from my parts stash.

I live in sunny CA, corrosion is not much of an an issue here (sun & heat are the great enemies; I lived in Michigan through the 1970's decade, so I'm familiar with corrosion)

Brad, good point for readers; I am aware of the pushrod adjustment, and I did that adjustment when I installed the first M/C, and I double-checked the adjustment for the M/C that the brake shop installed.

Again, my issue appears to be air bubbles in the right front front brake hard line that I haven't been able to eliminate despite extensive bleeding, but it's hard to understand why only the right, and why the air bubbles persist (even when bleeding from the steel brake line itself, ahead of the flex hose), yet apparently no fluid leakage/loss when everything is connected and the brake pedal is pushed. Pedal is soft, but not sinking.

When bleeding with the pedal-pump method, there was no sinking pedal with the wheel cylinder bleed valves closed, but the pedal was kinda spongy & middling height and never did reach the expected high & hard condition.

When I had the car on the road after the brake shop worked on it, the braking was so weak as to be downright scary to me; locking the wheels would have been impossible. The braking was fine before the car was left sitting a few years.

I did find a 5-year-old quote on stainless re-sleeving by "Karps Power Brake" in CA (east of L.A.)... it was $60 each + shipping both ways. Likely more now. I would also need to buy & install seal kits. http://www.karpspowerbrake.com/

Edited by WayneC
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Gunslinger, I overlooked this comment from you:

"Your car should have two blocks in the brake line...a distribution block which splits brake fluid to front and rear. You also have a proportioning valve which directs more fluid to the front than rear brakes since the front does most of the braking load. It's fixed, not adjustable so if there's a problem there it would have to be a clog in the line somewhere."

Actually there appear to be 2 pipes from the M/C, one to each side of the steel proportioning valve below the M/C, and 2 pipes coming out of the front of the proportioning valve, I assume one to the front brakes (with a junction block somewhere to send fluid to each front brake and each rear brake cyl). There is also a tube extending out of the front of the block with an electrical wire, I assume for a warning light. It is hard to see the block, I wish I had photographed it when I had the M/C out, but here is a photo of it installed...

http://www2.snapfish.com/snapfish/slideshow/AlbumID=5692985023/PictureID=277530940023/a=6083595023_6083595023/otsc=SHR/otsi=SPIClink/COBRAND_NAME=snapfish/

Edited by WayneC
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Thanks Wayne, that is a far better price! I'll have to update my bookmarks.

It does sound like you have air trapped somewhere in your front lines, doesn't it?

As for you distribution block, it looks similar to the one in my 73 but they must have changed some things around. There should be a proportioning valve built into it, though. There is another block on the frame that splits the front wheel line and has the brake light switch in it. A real pain to change those lines, too. I also eliminated the mechanical brake light switch and installed an electric one on the pedal, a worthwhile and easy modification.

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If all else fails, this bleeder attaches to the wheel cylinders and pushes fluid toward the M/C. That should be the most efficient way to remove air from the system.

I have one among my tools and it has yet to fail if retained air is the problem.

http://www.summitracing.com/parts/psl-2004?seid=srese1&gclid=COiEx9b__bsCFYhcMgodCj0AGg

Bob

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There is also a tube extending out of the front of the block with an electrical wire, I assume for a warning light. It is hard to see the block, I wish I had photographed it when I had the M/C out, but here is a photo of it installed...

http://www2.snapfish.com/snapfish/slideshow/AlbumID=5692985023/PictureID=277530940023/a=6083595023_6083595023/otsc=SHR/otsi=SPIClink/COBRAND_NAME=snapfish/

That is a pressure differential sensor...if there's a loss of line pressure it's supposed to activate the light on your dash as a warning. Like mine, it seems yours doesn't work either. I've never found a replacement or what else it fits as an interchange. I asked Jon Myer about it and he said it's been probably thirty years since he's seen one. He believes it's from a Ford was didn't know what year or model.

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I have the part # at home, but the distribution block from a 77 Mustang II (or Pinto w/disc brakes) is a direct replacement according to Gary Johnson (former Avanti dealer).

The only problem is it's an obsolete part and no longer made and I never have found one yet.

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Just realized I never did mention that my Avanti is a '71. I also own an '80.

Gunslinger, after some research I read that proportioning valves can do more than just warn you, they can actually shut off the side of the system that lost brake fluid pressure (dunno if my Avanti valve does that). And, I suppose it's possible for the valve to go bad, cutting off fluid to the front brakes. Even if the valve is not bad, but had purposely cut off fluid because of a leak in the front brake system (when I first started work on it, I did find the left front flex hose fitting was leaking), I wonder what restores the valve to it's normal position once it's been activated? Possibly by using the method Bob uses to pressure-bleed brakes from the brake cylinder end, thereby pushing the valve back to it's normal position? I'm not sure if that explains why I'm unable to vacuum bleed, though, I do get fluid, but always laced with bubbles. Actually, I think the MityVac may be able to perform that same reverse pressure-bleeding method, since it has a switch to change it from vacuum to pressure; I need to check the booklet that came with it.

In an eBay search, the closest physical appearance match I could find for the valve is one for a 1969 Corvette, but it's not a perfect cosmetic match, and the Vette has front and rear disks. Next closest valve I found was for a '67 to '70 Mopar, but the overall shape is not as close as the Vette and I couldn't find a picture showing the front side of that valve. Considering the Avanti master cylinder was a Chrysler design, I would expect the proportioning valve might be a Chrysler part as well (although there are also a couple of Ford master cylinders that can be used as Avanti replacements by adapting the brake line fitting sizes).

Edited by WayneC
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Master cylinders, proportioning valves and boosters may sometime look alike and fit the same, but may be different internally. They're designed for specific weight vehicles, brake combinations, etc. I'm not saying the parts won't interchange completely, but often they don't. As important as brakes are I wouldn't want to simply replace parts with others that simply fit.

Example...when the brakes on my car were completely redone...hoses, metal lines, etc., NAPA listed brand new wheel cylinders for half what wheel cylinders from Avanti vendors had them for. I bought two...the NAPA guide said they interchanged with a Jeep application. When they were installed, the rear brakes locked up immediately on brake application. It turned out that, while they looked identical and fit the same, the proper Avanti wheel cylinder bore is 3/4" and these for the Jeep were 7/8" diameter. The difference was enough to over-energize the rear brakes. My alternatives were to either get the correct wheel cylinder or use an adjustable proportioning valve and experiment to find the correct front/rear pressure. I ponied up and got the correct wheel cylinders.

Parts suppliers are simply consolidating part numbers for older cars to reduce parts to be inventoried at the warehouse and retailer levels. Apparently whomever put the NAPA catalog together didn't know the differences between otherwise identically appearing parts. The same goes for other parts houses as well (I ran into that with belts for my Corvette).

All I'm really saying is be careful when replacing parts with others that might fit and you don't really know if they're correct.

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I'm not sure what might have changed from 1971 to 1973, but I found this to be true for my car when doing my rear brakes after a lot of research:

he rear brake springs & hardware are from 66-73 jeep CJ type with 11" drums. The only difference is the color. These are old parts numbers from then Bendix H7137 or EIS H7137.  The rear wheel cylinders are from 78-86 ford fairmont station wagon, 73 ford fairmont and mustang 82-83 work. They are 13/16th cylinder cups.  The brake shoes are from chevy. I can't recall which model, but shoe number was wagner 228 Doug Greene  August 2003

From Bob Johnstone's site.

As for the distribution block/proportioning valve, yes the valve can shut off pressure to the side that has a drop in pressure (ie; a major leak). That's the idea of having a split braking system, you won't lose all your brakes in the case of a failure in either the front or the rear brakes. As for re-centering the valve, I think causing a loss of pressure on the other side can bring it back but I haven't had any experience with that.

Mine physically looks like an early Mustang distribution block and is bolted under the brake booster on a bracket with two bolts. If you look at one of the reproduction ones they make for a 70 Mustang/Cougar, that's essentially what I have. Here's one on eBay: http://www.ebay.com/itm/1970-70-Ford-Mustang-Cougar-Mach-1-Disc-Brake-Distribution-Block-D0OA-2B328-DX-/300853728632?pt=Motors_Car_Truck_Parts_Accessories&hash=item460c479578&vxp=mtr The proportioning valve is built into the rear brake side of it, since drum brakes will tend to lock up under heavy braking before disc brakes. I was convinced that was my problem, so I did a lot of research on that particular part. I have heard that some of the Chrysler units will interchange also, so I wonder if your has perhaps been changed before?

With Avanti's, it's hard to say what they did from year to year.

Edited by warren55
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There is a place called Apple Hydroulics in Calverton N.Y. They resleve anything and have been in business for many years. They generally get about $75.00 per sleve. They are big into British cars. You can google them for their #.

I have used them many times.

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Thanks, Tony, I've heard of Apple Hydraulics.

Their website lists prices for brass resleeving of small-bore wheel cylinders at $50, or $85 to also rebuild with new seals.

I've sent them an email asking about prices on the Avanti cylinders; I'll post their answer here if they reply.

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Warren, my proportioning valve doesn't look like yours. I don't think it's been changed, as the car is a 1971 and I purchased it in 1978, I think, with about 40k miles on it at the time; it looked entirely stock. It had an engine change in the mid 1980's, and frame-on restoration around 1990. I've never messed with the proportioning valve, and I've done most of the mechanical and electrical work on this car myself since I've owned it.

Edited by WayneC
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Warren

This is my brake setup out of the 74. I know it is OEM because I purchased it from the OP's family. The M/C is new but the proportioning valve is original. It looks like yours. I haven't checked closely but I think the 83 looks like this also. It probably doesn't matter but I can check the 83 if it's important.

P1020103_zps89bfad44.jpg

Bob

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Got a quick and courteous reply from "Lazar" at Apple Hydraulics (for brass resleeving)...

"(a) Take the cylinders off, take the pistons out and send us empty cylinders for resleeving. We return them cleaned, resleeved to original bore size (2.125") and ready for reassembly which you do with a kit you provide. Cost: $60 each cylinder

(Send us cylinders as they came off the caliper (with pistons still in). We return resleeved, cleaned, and assembled with new OEM seal kit, ready to bolt back on the caliper. Cost $95 each cylinder

© Send complete calipers. We will do (on each cylinder, clean the middle part and re-attach the cylinders. Cost: $285 each caliper ($190 to do two cylinders plus $95 for extra work). Add $30 each for new cross-over line installed.

Turnaround time is one week here, in the shop. You get same parts back (not exchange). For shipping from Calif.we recommend flat rate priority mail, it is half the cost and half the time compared to UPS. See http://postcalc.usps.com/ "

Edited by WayneC
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Yep, that looks like my setup alright. Only difference is my outlet for my front brakes on the master cylinder is on the other side. So the 71 is different, huh? I'm surprised, I wonder what else is different.

Here's a shot of mine. Probably the ugliest part of my engine compartment. I should find a way to paint the master cylinder. I have a new one, but see no reason to swap it at this point. It's nice you have NOS parts like that laying around.post-9535-0-99632000-1389839136_thumb.jpg (I suppose I should have just put the picture on photo bucket or somewhere else. This is is big as I can make it on this page!)

Edited by warren55
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