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I'm attempting to disassemble and repair an old (1950)wheel cylinder. The smart thing to do is to just go buy an over-the-counter replacement. Might have to at the end of the day but really want to reuse the original. Not a money thing. Anyway, my question regards applying heat. I know metal expands with heat and after cooling off returns to its original size. As you know, the cylinder is cast iron whereas the bleeder screw is steel. Should I focus the heat on the screw or to the cylinder where the screw is inserted? I know the heat transfers regardless so maybe it doesn't make a difference. Forgive me if this is a dumb question. Thanks in advance. Bill
PS. I've soaked the darned thing (days) in PB Blaster, parts cleaner, and a multitude of other lubricants. It's nearly as stubborn as me.
Heat the cast and yes it will heat the bleeder too. Let it cool below orange so you do not twist off the bleeder. I first try to tighten the bleeder if it is not overly tight, then try to remove it. Of course you know you will melt the rubber cups inside the wheel cylinder if you have not already removed them. Good to disassemble it first.
Heat the cast and yes it will heat the bleeder too. Let it cool below orange so you do not twist off the bleeder. I first try to tighten the bleeder if it is not overly tight, then try to remove it. Of course you know you will melt the rubber cups inside the wheel cylinder if you have not already removed them. Good to disassemble it first.
Here is the best way to remove a frozen bleeder screw. Find a nail or similar small rod that barely fits tight in the hole of the bleeder and tap it all the way in and trim it flush (the hollow bleeder is much more likely to break, this will make it almost solid). Heat the bleeder and immediate area with a torch and give the bleeder a few light taps with a hammer when it is cherry red. Quench the bleeder with a shop rag soaked in ice water and immediately loosen the bleeder with a wrench or vise-grip. Obviously you will have to replace the bleeder & rebuild your cylinder as the heat will likely damage the rubber parts but trust me, this works like a charm.
Here is the best way to remove a frozen bleeder screw. Find a nail or similar small rod that barely fits tight in the hole of the bleeder and tap it all the way in and trim it flush (the hollow bleeder is much more likely to break, this will make it almost solid). Heat the bleeder and immediate area with a torch and give the bleeder a few light taps with a hammer when it is cherry red. Quench the bleeder with a shop rag soaked in ice water and immediately loosen the bleeder with a wrench or vise-grip. Obviously you will have to replace the bleeder & rebuild your cylinder as the heat will likely damage the rubber parts but trust me, this works like a charm.
Never thought of the nail trick. Sounds logical. I also put paraffin wax (melt a candle) around the treads while it is hot. The heat draws the wax into the treads as it cools. A couple of raps with a hammer has also helped.
I think he may find the wheel cylinder is pitted after 60 years and may be heading to the parts store anyway.
I replaced mine and put the originals in the boxes the replacements came in and put them with the rest of the parts I changed out. The new future owner can decide what to do with them when I hand them to them.
Thanks everyone. Got it done. Have never heard about the wax trick so went that way for a new experience. Couldn't do the nail as the bleeder screw is as unique as the cylinder and knew I'd not find another just like it. Yeah, I know, who'd ever see the bleeder let alone the cylinder? Anyway, the heat just sucked that wax right in as you said it would. After cooling, the bleeder, with just a little persuasion, back out. Thanks, thanks, thanks.
Thanks everyone. Got it done. Have never heard about the wax trick so went that way for a new experience. Couldn't do the nail as the bleeder screw is as unique as the cylinder and knew I'd not find another just like it. Yeah, I know, who'd ever see the bleeder let alone the cylinder? Anyway, the heat just sucked that wax right in as you said it would. After cooling, the bleeder, with just a little persuasion, back out. Thanks, thanks, thanks.
Bill
Multiple good ideas all together work better. I guess you learned if you put the wax on too soon it will vaporize. Took me a while to learn the right time to put the candle to the threads.
Glad I could be a little part of the help.
Ron
Rebuilding wheel cylinders is generally a lost cause. The big problem is that when you hone all of the pits out the bore is larger than OEM. The seals only come in OEM size. You get the picture.
I've done what Randy G. did. I found new cylinders at Advance Auto and put the only ones in a bag.
The other option is to sent them to White Post and have them sleeved.
White Post is also very specific that you should not be using the silicone fluid that is currently available. It cause the seals to swell.
Let's suppose for a moment that White Post is correct. Why is it a bad thing for the seals to swell? Seems like that would contribute to good sealing.
My wife says softer is not better. As the seals get softer, there is more leak by and faster wear. She would rather have hard steel rings (with no gaps) than rubber that will flex over a bit of rust and leak.
I guess that is what she is talking about??? :total: Maybe not.
The problem is that the seals don't just "swell", they bloat, get soft and lose their strength (think of a dry sponge vs. a wet one. Also, I got the impression that the OP wasn't necessarily talking about a Corvette cylinder but maybe a different application that wasn't easy to replace???
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Wheel cylinder
