Master Cylinder 63 STD
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Safety Car
Joined: Mar 2003
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From: Philadelphia PA
Master Cylinder 63 STD
Working on overhauling the drum brakes, new drums, wheel cylinders, shoes, springs, etc. In looking at the MC, it looks like it could use a refresh. Was just going to buy a non-GM numbered replacement from a Corvette vendor and shelf the original. Then realized a simple Raybestos MC36242 would work as well and is cheaper. Anyone use one of these before? Any issues with them?
In looking at the shop manual, looks like it's as simple as removing the clevis pin and removing the nuts to the MC under the dash?? And then the MC should just come right out.
Does the rubber boot (under dash) need to be replaced if it looks fine?
This Raybestos MC looks like it comes with the foam gasket, but I think I still need the firewall gasket. Any other misc parts that I'm missing that I might need? Probably will replace the mounting bolts and nuts too.
In looking at the shop manual, looks like it's as simple as removing the clevis pin and removing the nuts to the MC under the dash?? And then the MC should just come right out.
Does the rubber boot (under dash) need to be replaced if it looks fine?
This Raybestos MC looks like it comes with the foam gasket, but I think I still need the firewall gasket. Any other misc parts that I'm missing that I might need? Probably will replace the mounting bolts and nuts too.
Safety Car
Joined: May 2014
Posts: 3,785
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Working on overhauling the drum brakes, new drums, wheel cylinders, shoes, springs, etc. In looking at the MC, it looks like it could use a refresh. Was just going to buy a non-GM numbered replacement from a Corvette vendor and shelf the original. Then realized a simple Raybestos MC36242 would work as well and is cheaper. Anyone use one of these before? Any issues with them?
In looking at the shop manual, looks like it's as simple as removing the clevis pin and removing the nuts to the MC under the dash?? And then the MC should just come right out.
Does the rubber boot (under dash) need to be replaced if it looks fine?
This Raybestos MC looks like it comes with the foam gasket, but I think I still need the firewall gasket. Any other misc parts that I'm missing that I might need? Probably will replace the mounting bolts and nuts too.
http://www.amazon.com/Raybestos-MC36.../dp/B000MLAJKS
In looking at the shop manual, looks like it's as simple as removing the clevis pin and removing the nuts to the MC under the dash?? And then the MC should just come right out.
Does the rubber boot (under dash) need to be replaced if it looks fine?
This Raybestos MC looks like it comes with the foam gasket, but I think I still need the firewall gasket. Any other misc parts that I'm missing that I might need? Probably will replace the mounting bolts and nuts too.
http://www.amazon.com/Raybestos-MC36.../dp/B000MLAJKS
That being said there is no need to go under the dash for anything except adjust the pedal free play per the assembly manual. If you remove the bolts at the firewall the M/C should come right off and the clevis and rod will stay in the car.
The rubber boot is fine to reuse.
Melting Slicks
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From: Syracuse, NY and Clearwater, FL
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From: Greenville, Indiana
Thread Starter
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From: Philadelphia PA
It is the original, so I will be keeping it. I'll take some pics later today and post them up. When you see the pics, you'll understand why I want to just replace with an aftermarket.
But I guess if the bore is not pitted, I could rebuild it. The issue is that it's kind of rusty. Could I just take the MC apart and put the main unit in some evaporust? Didn't know if that was the correct approach. I don't have a blast cabinet.
But I guess if the bore is not pitted, I could rebuild it. The issue is that it's kind of rusty. Could I just take the MC apart and put the main unit in some evaporust? Didn't know if that was the correct approach. I don't have a blast cabinet.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Here is what I do with a rusty cylinder.
Mix up a 10-1 solution of water and 30% muratic acid. Strip the cylinder of the guts and drop it in the acid solution. After 10 minutes or so pull the cylinder out and rinse it. If the rust isn't gone it's back in the acid for a few more minutes.
Rinse it off and scrub with Castrol Super Clean and blow dry.
Get a small wad of Scotch Brite pad and wrap it around a drill bit. Shove the SB in the bore and start the drill, moving the pad back and forth. After a few passes, you'll have a nice clean bore. You can then inspect for wear and pitting. If the bore needs honing you can do it now.
Before it comes up, yes I know about the effect acid can have on metal. So far, using my method I have had no problems and don't expect any. I have cleaned all sorts of engine and chassis parts using this method. I not advising anyone to do it, just what I do.
Mix up a 10-1 solution of water and 30% muratic acid. Strip the cylinder of the guts and drop it in the acid solution. After 10 minutes or so pull the cylinder out and rinse it. If the rust isn't gone it's back in the acid for a few more minutes.
Rinse it off and scrub with Castrol Super Clean and blow dry.
Get a small wad of Scotch Brite pad and wrap it around a drill bit. Shove the SB in the bore and start the drill, moving the pad back and forth. After a few passes, you'll have a nice clean bore. You can then inspect for wear and pitting. If the bore needs honing you can do it now.
Before it comes up, yes I know about the effect acid can have on metal. So far, using my method I have had no problems and don't expect any. I have cleaned all sorts of engine and chassis parts using this method. I not advising anyone to do it, just what I do.
Last edited by MikeM; May 16, 2014 at 07:12 PM.
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Muriatic acid WILL eat cast iron up so you have to be careful when soaking. Muriatic acid solutions will clean many metal parts on a Corvette. I think it's aggressive enough that a person shouldn't douse any valuable metal parts in it until he gets a handle on how his solution works.
Muriatic 30% acid is used to clean swimming pools. You can buy it at WalMart or any pool supply place..
Thread Starter
Safety Car
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From: Philadelphia PA
So here is what I am dealing with. Never used muriatic acid before and I would hate to screw something up. I've used evaporust with good success before, so I'm wondering if I should try that first.
I guess a rebuild kit would be cheaper and then I don't have to shelf the unit. Looks like the shop manual has a write-up on the rebuild.
So besides the rebuild kit, I should probably get the firewall gasket and probably some new bolts and washers. Anything I might need while I'm putting in the order?
I guess a rebuild kit would be cheaper and then I don't have to shelf the unit. Looks like the shop manual has a write-up on the rebuild.
So besides the rebuild kit, I should probably get the firewall gasket and probably some new bolts and washers. Anything I might need while I'm putting in the order?
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I tried a trial with Phosphoric acid. I think it was on carburetors. Don't remember though. I know I have a almost full bottle left so whatever I was trying to do must not have gotten me to the moon.
Muriatic acid WILL eat cast iron up so you have to be careful when soaking. Muriatic acid solutions will clean many metal parts on a Corvette. I think it's aggressive enough that a person shouldn't douse any valuable metal parts in it until he gets a handle on how his solution works.
Muriatic 30% acid is used to clean swimming pools. You can buy it at WalMart or any pool supply place..
Muriatic acid WILL eat cast iron up so you have to be careful when soaking. Muriatic acid solutions will clean many metal parts on a Corvette. I think it's aggressive enough that a person shouldn't douse any valuable metal parts in it until he gets a handle on how his solution works.
Muriatic 30% acid is used to clean swimming pools. You can buy it at WalMart or any pool supply place..
I've used phosphoric acid with great success on aluminum and pot metal FI parts. So I'm comfortable with it and know what to expect.
On rusty steel and iron, phosphoric acid affects the rust but it seems to need help. Being a lazy sort, I don't want to offer the help if I don't have to.
Jim
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Safety Car
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From: Philadelphia PA
So the MC cleaned up pretty nice with the Evaporust product. Safe, non-toxic, biodegradable, etc. I have a rebuild kit on order UP393 from Napa.
The bore looked nice and smooth, no pitting.
The date code is A-5 3, that means January 5 1963 right?
Next step is to paint it. After rinsing the Evaporust off the MC, it flash rusted, any ideas on how to prevent that? Can I just rattlecan the MC with the light orange tint? Or should I re-rinse, dry and immediately paint?
From the research, it looks like the correct paint color is a semi-gloss black? I read Krylon had a product 1613, but it's been discontinued at the retail level. Any suggestions on a similar rattle can product?
Does the inside of the reservoir where the brake fluid goes get painted? I would think not, since the paint could get into the holes where the fluid has to travel and induce some blockage. Or do I just tape off the holes at the bottom of the reservoir, the nipple/flare outlet, and the bore and go nuts with the rattlecan?
The bore looked nice and smooth, no pitting.
The date code is A-5 3, that means January 5 1963 right?
Next step is to paint it. After rinsing the Evaporust off the MC, it flash rusted, any ideas on how to prevent that? Can I just rattlecan the MC with the light orange tint? Or should I re-rinse, dry and immediately paint?
From the research, it looks like the correct paint color is a semi-gloss black? I read Krylon had a product 1613, but it's been discontinued at the retail level. Any suggestions on a similar rattle can product?
Does the inside of the reservoir where the brake fluid goes get painted? I would think not, since the paint could get into the holes where the fluid has to travel and induce some blockage. Or do I just tape off the holes at the bottom of the reservoir, the nipple/flare outlet, and the bore and go nuts with the rattlecan?
Safety Car
Joined: May 2014
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So the MC cleaned up pretty nice with the Evaporust product. Safe, non-toxic, biodegradable, etc. I have a rebuild kit on order UP393 from Napa.
The bore looked nice and smooth, no pitting.
The date code is A-5 3, that means January 5 1963 right?
Next step is to paint it. After rinsing the Evaporust off the MC, it flash rusted, any ideas on how to prevent that? Can I just rattlecan the MC with the light orange tint? Or should I re-rinse, dry and immediately paint?
From the research, it looks like the correct paint color is a semi-gloss black? I read Krylon had a product 1613, but it's been discontinued at the retail level. Any suggestions on a similar rattle can product?
Does the inside of the reservoir where the brake fluid goes get painted? I would think not, since the paint could get into the holes where the fluid has to travel and induce some blockage. Or do I just tape off the holes at the bottom of the reservoir, the nipple/flare outlet, and the bore and go nuts with the rattlecan?
The bore looked nice and smooth, no pitting.
The date code is A-5 3, that means January 5 1963 right?
Next step is to paint it. After rinsing the Evaporust off the MC, it flash rusted, any ideas on how to prevent that? Can I just rattlecan the MC with the light orange tint? Or should I re-rinse, dry and immediately paint?
From the research, it looks like the correct paint color is a semi-gloss black? I read Krylon had a product 1613, but it's been discontinued at the retail level. Any suggestions on a similar rattle can product?
Does the inside of the reservoir where the brake fluid goes get painted? I would think not, since the paint could get into the holes where the fluid has to travel and induce some blockage. Or do I just tape off the holes at the bottom of the reservoir, the nipple/flare outlet, and the bore and go nuts with the rattlecan?
Safety Car
Joined: May 2014
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I also want to add that with fluid that looks the old/dirty, flush that system very good and inspect all the brake lines and hoses you can see. Keep it running until it's clear, we are talking brakes here and a important safety issue.
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From: Greenville, Indiana
I rinse in a bath of Castrol Super Clean followed by a bath in a baking soda/water rinse followed by plain water. Sometimes I follow with heating the part with a propane/butane torch to dry it quickly.
Thread Starter
Safety Car
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From: Philadelphia PA
The CSC won't hurt the cast iron? Just straight solution or mix? What does the baking soda/water rinse do?
Team Owner
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From: Greenville, Indiana
Thread Starter
Safety Car
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From: Philadelphia PA
Well a month later, still working on the brakes...
Took another look at the original MC and decided to just shelf it and have it rebuilt when I do the frame off restoration sometime in the early 22nd century...
That being said, I ordered a new Raybestos MC and will use that instead. Need to bench bleed and install.
My question is around the rubber boot that goes over the cylinder rod, is there supposed to be some sort of lubrication you are supposed to put on the cylinder rod? The boot seems like a tight fit over the rod and would seem that everytime you apply the brake pedal, the boot would get folded up...if that makes sense.
Took another look at the original MC and decided to just shelf it and have it rebuilt when I do the frame off restoration sometime in the early 22nd century...
That being said, I ordered a new Raybestos MC and will use that instead. Need to bench bleed and install.
My question is around the rubber boot that goes over the cylinder rod, is there supposed to be some sort of lubrication you are supposed to put on the cylinder rod? The boot seems like a tight fit over the rod and would seem that everytime you apply the brake pedal, the boot would get folded up...if that makes sense.
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Army
The boot is sort of a bellows arrangement and should move in and out with the M/C push rod and therefore doesn't need any lube. BTW - '64 M/Cs are relatively common and work well on the '63s (that's what I have as see in the picture). You didn't mention brake hoses in your original post - damn sure change those too !!
There is also a foam seal at the firewall in addition to the boot (see picture)...
There is also a foam seal at the firewall in addition to the boot (see picture)...
Thread Starter
Safety Car
Joined: Mar 2003
Posts: 4,527
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From: Philadelphia PA
Cool, thanks for the pic FTF!!
Yeah, the Raybestos unit looks like a nice unit and came with the foam seal as well. Funny, it's stamped Made in the USA on the unit, but indicates it's Made in Mexico on the box...
The shop manual makes reference to installing the pipe plug and tighten securely in one of the last steps in the MC assembly. I see no picture reference to this pipe plug. What is this pipe plug they speak of?
Yeah, the Raybestos unit looks like a nice unit and came with the foam seal as well. Funny, it's stamped Made in the USA on the unit, but indicates it's Made in Mexico on the box...
The shop manual makes reference to installing the pipe plug and tighten securely in one of the last steps in the MC assembly. I see no picture reference to this pipe plug. What is this pipe plug they speak of?