The Stovebolt Site Forums The Shop Area Driveline brake bleeding WITHOUT using bleeder screws???

My wheel cylinder bleeder screws are hopelessly seized. did every trick in the book to loosen them to bleed my brakes. So, with out using the wheel cylinder bleeder screws, can the brake system be bleed of air in the lines? the system is completely assembled, theres no fluid right now in the lines. I know I can re-buy all the wheel cylinders, or destroy and retap the bleeder screws, just hoping someone has another way before I go that route. could / would the frame "T" line connection possibly be used to bleed?

Since the bleeder screw is at the highest point of the wheel cylinder, there's no practical way to do a good bleeding job if they're siezed up. I have freed up bleeders by totally dismantling the wheel cylinder, and heating the bleeder red hot with a torch. By the time you do that, there's enough labor time, plus the price of a rebuild kit, that it's more practical to just replace the cylinder. Is it worth betting your life on the cost of a few brake parts?

I've gotten very cautious in my old age! The very best brake work I can do is just barely good enough!
Jerry

Take the time and effort to either remove and replace the bleeder screws or find cylinders with good ones.

I have found very few screws and bolts that were truly stuck.. I've removed dozens and dozens of stubborn fasteners by various methods, and only a few have had to be drilled and re-tapped.

Grigg

If you're bleeder screws were as stuck as mine, you're better off to buy new ones. Only one came out of the wheel cylinders. The other three either broke of or when you heated up the wheel cylinder they didn't budge. After a two weeks of hammering/heating/trying to turn the screws I got some help from people on this site who must really like me and am waiting on 4 new wheel cylinders/shoes.

I have bled them by removeing one piston & sticking a small screwdriver in the top of the cup. That will only work when the rest of the system has not been opened or the master cyl get low. It also will only work when the master cyl. is on the firewall & you can gravity bleed it. You should go ahead & get new cyls. Bleeders & mounting bolts break pretty often around here as we are in the rust belt.

I would not heat it with a torch. Buy new. If you don't have the money to buy new wheel cylinders, at least take them off, put them in a jar and let them soak in something like PB Blaster (penetrating lube). That might loosen up the bleeder screws.

I've learned over the years that for some reason it always seems to help to try tighten things a little before trying to loosen them. It may be a myth but it does seem to help and if it budges the least little bit then some penetrating oil will work better and faster. Works for me...how about others?

Yep Alvin, it does seem to work. I don't know why other that the fact that rust may have not gotten up farther than the end of the nut or bolt and tightening helps break that bond between rust and metal?

i always have the best luck by taking the cyl off and putting it in a vise. i use pb blast and a big set of vice grips. it's a lot easier with it off when you can stand up and get a good "scald" on it. hr

If the bores of the wheel cylinders are good and not pitted badly they can be saved. Do like hoggyrubber said mount them in a vise and drive an allan wrench in the borer of the broken bleeder. This wrench must fit really tight if you cant find a tight fit measure the flats of the next size bigger allan wrench and drill the bleeder this size and broach the wrench into the hole. When this is done heat the casting around the broken bleeder really hot with a torch and remove the offending bleeder with the allan wrench you drove into it. I've used this method miny times without fail with no damage to the cylinder. A allen wrench makes a really good easy out as they will not break off in the hole and tend to be a little springy.

Also the cylinders can be taken apart at this time with a greese gun with out damaging the spring or pistons. The old hammer and punch method will generaly ruin both.

Frankly, I would expect that if the bleeders were rusted in place that completely, the bores of the cylinders would have rust in them, too. If it were me, I'd get new ones. Come to think of it, I just did. The master cylinder and all the wheels cylinders on my '51 GMC (last licensed in 1976) were rusty to varying degrees. Two of the wheel cylinders might have been salvageable. Didn't do it - I replaced with new all around. That's your life you're talking about - brake failures don't always give second chances.

David Bush

I guess I just don't like throwing a way rebuildable american made parts and buying crap from china. The last complete brake system I rebuilt had been sitting sense the early 70's and the only new parts purchased were lines and rubber parts. This project took the better part of two weekends to complete with a total price tag of about $80, and that includes all new liners for the brake shoes hand riveted by myself. With a little time and patients old parts can be saved and successfully rebuilt with no ill effects.

I was just trying to show the young lad how to save a few bucks and maybe learn some skills. I started out 40 years ago just like this boy with a 49 Chevy with no brakes didn't matter it didn't run either. With guidence from a old time mechanic who showed me how to fix things the old Chevy was repaired with very little money spent.

Yes, I bet my life and everyonelses I meet on those old used not rusty anymore 62 year old parts. My life is in my own hands not a 6 year old kid in china making cheep knockoff parts.

Thanks for all the advise. obviously these days money is a good motivator to try to salvage american made OEM parts, if possible. I am with ttodd on taking time and patience with old parts to make the salvagable, And I want to thank ttodd for calling me young lad!!!! I'm new to the site, but have been working with these 55-59 chevy trucks for 30+ years. Just now and then you run into an odd situation that you need a little help with. Guess this case is closed, (are you ready for this one), my daughter works at a elderly care facility and when I picked her up I had one of the wheel cylinders with trying to gett the bleeder screw off while i waited for her, a really, really old timer came up and told me he was a mechanic for 70 years and he knew how to get the bleeded screw loose, I told him I was all ears, he said take the 4 wheel cylinders off, strip them down to only the cylinder and the stuck screw, throw all 4 of the wheel cylinders into a stainless steel bowl and pour Coke cola on them until they were covered, and leave it for a day or two. Yup you guessed it, they all loosened up and came off. He also said not to use heat, it will screw up the rubber if you heat while on the truck with the wheel cylinder still assembled. He said the acidity of the soda eats the excess metal away, and the syrup creeps into all the crevaces and loosens stuff up. crazy huh! I want to thank everyone for chiming in on helping this young lad with the brakes. i try whenever possible to reconstruct and re-use old oem parts, but I know when to throw in the towel and buy new.

Wow, I knew Coke was a useful cleaner but didn't know that it would do that!!! I'll keep that in mind the next time I need something loosened.

if you send off the wheel cylinders and have them sleeved with s.s. plus the mc. never have to worry about them again. really a practical idea when you figue most of these trucks sit the majority of the time.

Hey ttodd,

Put yer dukes down there. I'm all for reusing and rebuilding anything I can (if you saw my '51 GMC you'd see that right away). Wish I could buy repop American made parts, but when your wheel cylinders are so full of rust that the pistons are seized, it's time to get new, even if the only parts you can find are from China. I got my wheel cylinders and master cylinder from Obsolete Chevrolet. Although I've not driven the truck much yet, I'm not seeing any leaks or problems from these parts.

David B

Brakes are MORE important than going anywhere.

'''''''''''' My wheel cylinder bleeder screws are hopelessly seized.
&&
If the bores of the wheel cylinders are good and not pitted badly they can be saved. ''''''''''''

SO what's a new cylinder cost vs you trying to rebuild one from scratch?????? $$30.each and they're still pitted a little...
that makes NO sense to me

I've used AIR to blow apart the cylinders.

DID U read what BIG John said about some young mans truck his grandfather gave him. when the youngster drove it the brakes failed at his farm going downhill and the boy jumped out ONLY to have the truck still somehow hit him
w/ 72 operations and 100+ pints of blood at teenage yrs ............................

It's your life
HELLO


Ps ... you're all back east or midwest

read
http://www.classicperform.com/TechBook/BrakeBleed.htm

I cut and pasted this from another thread, and I personally recommend:

If you ever can't get new cylinders, or just want some to last near forever, have the old ones stainless steel sleeved. DON'T mess with brass sleeves.

The guy to have stainless sleeve your cylinders is:
Mark "the machinist" Frappier
82 Mountianview St.
Agawam, MA 01001
413-789-4588, or 800-528-5235

You send him your bare, stripped, clean cylinders, and he sends them back with a perfect looking stainless insert.
You will still need to go to NAPA and get rebuild kits, or perhaps Jim Carter sells kits?

Grigg

I had a master cylinder from my '46 1/2 ton sleeved with brass at White Post in Virginia in 1997. I just had to put a rebuild kit in it because the rubber parts got old and started leaking. Inside bore of the inserted sleeve still looked like new. $15 master cylinder rebuild kit and I'm back on the road with rock solid brakes.

My $.02

David Bush

With a little research, it's still possible to buy new original-equipment brake parts, not Chinese repops. If that's not an option, sleeving certainly is. I'm in the process of doing a total brake rebuild on a 1951 Chevy 2-door hardtop, with Huck brakes. When it hits the road, it will be as good as, or better than new.

Using heat to loosen rusted-in bleeder screws is not a problem, as long as the wheel cylinder is held in a vise, or something similar to absorb the heat that's transferred away from the bleeder screw. Get the bleeder red hot quickly with a big acetyline torch flame, tap it with a hammer once or twice, and use vise grips to turn it loose. No warp, no damage, and all it takes to get back in business is a new bleeder screw and a wheel cylinder kit, assuming the bore isn't pitted badly.
Jerry

So I have gotten all of the bleeder screws out w/ no issues after the coka cola trick. now I have everything re-assembled. i closed off all the bleeder screws except the farthest one from the master cylinder. I filled the master cyl. and pumped the pedal, this seemed to displace air in the master cyl and the fluid goes down, I've have the master cyl drop to half full 3 times and refilled it. the pedal needs to be pushed all the way to the floor to get the master cylinder to bubble and move fluid.
I have not had fluid travel to the farthest wheel yet, since no fluid has come out of the bleeder, so I closed that bleeder screw and pumped the brakes and the pedal still is to the floor, and no changes in the pressure it takes to push it down. I was thinking w/ the system closed, pressure would build and I could bleeed off air, but nothing.

I have now left the bleeder screw out thinking at some point gravity flow will get brake fluid to this wheel cylinder. I've never had a totally empty brake line system to contend with before. I dont own any tools, kits etc. to draw the brake fluid into the system further. I am thinking my master cylinder is ok since it does seem to push fluid. so since its looking like a week now w/ no "gravity flow" filling my lines, my question is this. Anyone out there got a way to push the fluid everywhere I need it? does the fluid need to be drawn through the system w/ something I need to go buy? I do not appear to have any leaks anywhere, but I imagine fluid isnt present through out the lines yet. I realize the air needs to be displaced to get the fluid pressure correct. Any discusion or help would be greatly appreciated.

If you do a search, I beleive that several on the site have made their own pressure bleeders for doing this. Personally, I gravity bleed first, then do the pedal pump thing. Unless you have installed speed bleeders, one thing you don't want to do is pump the pedal with the bleeder open, as this will allow the system to draw air in through the bleeder. A trick I do is to have a helper slowly pump the pedal while I hold a finger over the bleeder screw opening (finger acting as a one way valve) until the fluid comes out, then go on to the est of the bleeders. One thing I will mention, you should start bleeding from the longest line, not necessarily at the one futhest away from the master. In the case of the '55-'59s, that would be the left rear.

This is the reason you bench bleed. First off did you replace or rebuild the master cyl.? Take the tube loose from the back of the master cyl. Hold a finger over the hole & pump the pedal from the back position to a little way down. Keep doing this till you get pressure on the outlet & no bubbles come up through the reservoir. Then hook up the tube & bleed at the wheels. Speedy bleeders will help or use a helper. When the helper pushes the pedal down close the bleeder & the helper lets the pedal back.I had a pressure bleeder for years & never used it. I have a sucksion type now & have never used it for brake bleeding. You must have a good fresh master cyl. though. If the tiny hole under the little funnel in the resorvoir is stopped up it will never bleed right. When you get the brakes right on these trucks there is barely any movement in the brake pedal. You just apply pressure.

Ive been following this thread and just want to ask ..did you replace the rubber flex line that goes from the frame to the rear axle???...when i rebuilt my system and drained it, the fluid ran outta the rear lines quicker than my ExWife cashin the support check but when i went to bleed the ALL NEW system other than that rubber flex line i encountered your same probs ..coul not get fluid to teh rear wheel cylenders ..found my flex line had collapsed inside and was junk...replaced it and had brakes in 15 minutes.
Tim

I just completely replaced the entire brake system on a '51 GMC 1/2 ton. New master cylinder, new wheel cylinders, all new lines and all 3 new flex hoses. I made a down and dirty master cylinder bench bleeder out of part of the old brake line with its fitting from the master cylinder. I cut the line short and added a piece of clear flex hose to it. Bolt up the old piece of brake line and run the clear hose back into the top. Leave the filler cap off. With the MC clamped in the vise (Level!) fill it with fluid, then gently pump the plunger. You'll see lots of bubbles coming through that line. Keep at it (it takes a while) until you get a completely clear stream of fluid with no bubbles. I then pulled the clear line out of the cylinder and loosely screwed on the cap. I didn't remove the MC bleeder line from the back of the MC.

I took the cylinder to the truck (still full of fluid) and mounted it. My manual says to attach the clevis that holds the push rod to the bottom of the brake pedal first, but I didn't. First I unscrewed my homebrew MC bleeder and ran in the new line from the brake system. Not too much fluid came out. Then I went ahead and set toeboard clearance and hooked up the clevis. Bleeding the brand new system wasn't hard from that point. For my truck it's driver rear, driver front, pass rear, then pass front. Hope this helps.

David Bush

I took all of your advise and went back to the truck this afternoon and I now have fluid to the rear wheels. I closed the bleeders and pumped the brake pedal. The pedal still really had no give back to it, and no bubbles appear in the master cyl anymore when the pedal is pumped. I know theres fluid to the rear wheels because I had a connection not tight enough and fluid came out there with force.

No, I did not rebuild the master cylinder, and yes, I did notice it is dripping fluid from the piston end at the shaft ( the front of it). So I will need to rebuild it or replace it. anyone want to chime in on if rebuilding is ok? is it basically the same as rebuilding the wheel cylinders?
Thanks by the way for all the advise. its better to hear the good and even the bad instead of wasting a day trying to figure it out on my own.
I guess I will need to do the whole process over when I remove the master cylinder to replace or rebuild.

The commonly done way of rebuilding the M/C back before the days of lawsuit-happy customers and their Great White Shark lawyers was to rebuild the unit with it in place on the frame. There's a BIG nut at the rear of the cylinder where the main brake line attaches that would usually come loose with a couple of licks at one corner from a flat-ended punch and a big hammer, and the piston and a couple of check valves could be changed out. No problem, if the bore wasn't pitted.

I'd reccomend pulling the M/C off the frame, give it a good inspection and hone job, wash it thoroughly with alcohol, and reassemble with a rebuilding kit. Back on the frame, top off with fluid, and bleed the system again. If you leave the pressure line slightly loose as you fill the reservoir, it will gravity-bleed pretty well and minimize the effort of purging the air out of the master cylinder bore.
Jerry

Thanx hotrod lincoln, sounds like good advise to me. i will try the rebuild kit.

Received the rebuild kit and going to give it a try. I assume I spin off the knurled end (master cylinder end facing back)and pull everything out, hone it and slam everything back into the master cylinder. anyone have step by step instructions on rebuilding a master cyl.? I looked through Carolines Truck sites and didnt see any thing on this

Its pretty basic mechanics. You can take the snap ring out of the front & pull the pushrod. & thick washer. Pull the rear end like you described. Hone it out & put it back like it was. The rubber washer goes in the rear. Put the new check valve on the old spring. I think I mentioned before. There is a tiny hole inside the reservoir under a funnel shape. Poke a tag wire in to make sure it is clear. the rubber cup faces the rear.

I hope you guys won't mind if I jump-in here with my own question since it is related. I pulled my MC (1951 3/4T) to install a new kit. But the tiny hole that Wrenchbender referred to (compensating port) appears to be blocked. I've tried to push a tiny wire through the hole but it won't go. When looking into the cylinder with a flashlight I don't even see the other end of the hole. The bore of the cylinder is in good shape, not pitted or corroded, so I would think I would be able to see the hole. I haven't honed the cylinder yet, do you think that would free-up the end of the hole? Would a machine shop be able to drill-out the hole? Any help would sure be appreciated. Thanks!
Dale

Wow it is amasing what these old timers know.
I also had heard you can use coca cola in your radiator in an emergancy.

Wrenchbender Ret.

you dont happen to have a schematic or a exploded view drawing of the inside of this single master cylinder do you? I used the "socket tap everything through" method to get the innards out of the cylinder and I hate to admit it but it all shot across the garage and I have no idea what goes where in there. Luckily the rebuild kit has a part for each part that shot out, but as far as what goes where?? no idea. I looked through my 56 shop manual, and about a dozen websites and everyone has a written desc. of whats goes where, but kit-wise. all the parts are pretty much the same. I need a drawing showing the pieces and their order of assembly. any help on my latest delema would be very appreciated.

I probably have something at the shop but I believe I can describe it. There isn't too much to it. If the flat rubber washer snaps over a coller on the big nut at the back of the cyl. put it on . if not put the nut in the cyl. with the new matal ring. Put the flat rubber washer in the cyl. so it lays up against the nut in the back. Put the new check valve on the old spring & put it in the cyl up against the rubber washer. Put the rubber cup in the cyl. with the open side to the rear. Put the piston in the cyl with the rubber cup end to the front. Put the new boot over the push rod. Put the push rod & thick metal washer in the cyl holding it in & put in the snap ring. Then put the boot over the cyl.

we did good wrencbender, all in place master cyl rebuilt. pressue on pedal. last issue is a rear wheel cylinder squirts fluid out the front when pressure is applied. I am going ot try rebuilding it, or replace it.

Just note about taking out the frozen bleeders on a wheel cylinder. I found a tool on line that is made to take out the bleeders without breaking them. I can't find the web page now, but it consisted of a socket with a rod that went into the bleeder valve. The rod keeps the hollow valve from collapsing on itself, which is why they break off. I didn't buy the tool, but I did blast the valve with PB Blaster, put a piece of filler rod the same size as the valve, or was it a drill bit? But I got my bleeders off without breaking them. Might help if you are having trouble. Better than drilling out broken valves. Although I like the Coke trick.

Another good tip for dealing with stuck bleeder screws:

I am working on my 1960 Viking 2 ton, and I have found that if you use a pointed pic-tool (one that is hook-shaped at the end works great along with a straight one), you can scrape away all the rust and debri that has settled into the threads of the bleeder screw. By scraping all that minute particulate off the threads (and especially right up and around the threads going into the brake body), you can then soak it well with PB Blaster and the lube will penetrate much better. Also, when you go to loosen the bleeder screw, there will not be that encrusted crap to resist the turning action.

I like the idea someone mentioned about inserting a small drill bit piece into the bleeder to strengthen it as you apply pressure.

dwight

Getting setup to rebuild the Master and rear cyls and just happened to check out this page today all I can say is wow fantastic advice and instructions.

Just replace your newly unstuck bleeder screws with stainless steel speedbleeders. Now they will never seize again and you wont have to wait until your wife is in a good mood to bleed your brakes. Everybody wins!