Bleeder screw sealant
- Thread starter buck91
- Start date
For the years of my Subarus, the calipers and wheel cylinders are made out of steel thankfully not aluminum. So far, no dissimilar metal galvanic corrosion or stuck bleeders even after years in the rust belt.
If you are in the salt- make sure the rubber caps go back on the nipples- this is better than any thread goop you put on.
As mentioned Speed Bleeders have a colored compound on the bleeder threads.
From the first graphic/diagram on the linked page below:
Patented thread sealing system displaces air and moisture during thread engagement as well as eliminates air being pulled back into the system during bleeding.
From the first graphic/diagram on the linked page below:
Patented thread sealing system displaces air and moisture during thread engagement as well as eliminates air being pulled back into the system during bleeding.
Domestic Cars Application Guide - Speed Bleeders - Russell Performance Products
Russell Performance Speed bleeders are your ultimate solution for bleeding brakes systems, and can be performed by a single person. Available for many popular applications.
ps.russellperformance.com
- Joined
- Oct 28, 2014
- Messages
- 1,187
Well spoken. I actually do both, or all three you could say. I have anti-seize on the bleeder threads, waterproof grease on the exposed part of the bleeders, and push rubber caps on. I live in the salty Midwest, and it's been a looong time since I had to mess with "stuck" bleeders. For these little tips, I owe gratitude to Trav, the Critic, clinebarger, and a few other users on BITOG who are treasures.
- Joined
- Oct 7, 2013
- Messages
- 104
DO NOT DO THIS. DO NOT let silicon near standard brake-fluid. It's frightening what you'll read on these forums.
And worse, someone else thanked him? And, stands back.... the logic? Oh dear, oh dear.
Standard brake-fluid (DOT 3; 4; 5.1) is glycol base. Silicone, and er... glycol ( a from of alcohol) do not mix.
The clue's in the name... "gly".... 'col' and er... alcohol. It's in the Latin. Red rubber-grease is vegetable-base, usually Castor oil, it is compatible with glycol. Silicon grease is not. DOT 5 is silicon, use silicon-grease for DOT 5 silicon fluid only. DOT 5 is the purple stuff. The only grease which may come in contact with glycol brake-fluid (DOT 3; 4; 5.1) not 5, is red vegetable-base.
Please if you don't know what you're talking about fine... I don't know too much about DIY dentistry, I consult a pro.
There's three greases used in most brake set-ups. You'd use:
a) Copper-nickel grease on metals, NOT near rubbers; NOT near fluid.
b) Red vegetable grease where in contact with glycol.
b) Silicon to non-fluid side of rubbers. AWAY from glycol fluids. Metal if you like.
Reasons: The rubber in contact with fluid will be EPDM. EPDM is the king. EPDM is near invincible with all greases, your problem is the fluid won't be. Your caliper pins will have gaiters, these likely won't be EPDM. Probably cheaper, maybe Nitrile if you're lucky. Don't put copper-grease to those gaiters. Silicon works here. Silicon grease is stable with rubbers so won't attack any. Red grease is no use anywhere away from fluid, it washes away. Copper-grease goes where there's no rubber. Or... only put copper-grease on rubber when you know for fact it's EPDM - only, it's doubtful you will know.
if you DO rebuild calipers with silicon using Standard brake-fluid (DOT 3; 4; 5.1) expect woe.. A gloop will form as the glycol reacts with silicon. This won't be good. This gloop breaks into a snow and is near inert (hence there are no easy solvents) and this will clog ABS pumps filters etc. Without complete strip-down, and an air-line through all of it, it's a pig and near impossible to remove.
As for bleed-nipples, The rubber-cap is there to help. Silicon, copper or nickel grease. Needs must, bathroom-sealant if that's what you've got?... anything to stop the wet getting in there and corroding the lot together for next time is good. It's a parallel thread, not taper. Thus worry if it's not the cone that does the actual sealing. You would put actual thread-sealant on there if using a vacuum-bleeder; bleed-valves; MityVacs etc etc. Good for vacuum bleeds, good for keeping the wet out.
As I said, just watch what you put near brake-fluid, and for similar reasons don't mix brake-fluids of different types... no matter what it says on the tin. Two differing fluids mixed will nearly always lower the boil-point. Idiots on here banging on about upgrades to DOT5.1 from DOT3 or 4 only taking into account manufacturer boil points, WITHOUT the mix, or flushing nearer a gallon through are... well, ahem, that's another thread.
Last edited:
Silicone is already a gloop.
It also doesn't dissolve in alcohols or glycols as you claim:
- Joined
- Oct 7, 2013
- Messages
- 104
Clarity. 100% silicon won't dissolve with glycol, didn't say it did. Silicon grease is not miscible with brake-fluid, whereas red grease is. Silicon grease is not pure silicon. Dependent on formulaltion, it's thickeners etc will not go well with glycol. It won't stay put, and will float around, maybe where you don't want it.. Maybe not. At best you are set to get a mess, or far worse. Don't do this.
Last edited:
How, pray tell, is it going to "float around" in the brake fluid if you've applied it (sparingly, as common sense would dictate) to the threads of the bleeder screw? We're not talking about putting it in the brake fluid reservoir.
- Joined
- Oct 7, 2013
- Messages
- 104
Confusion reigns. You wrote:
Only it seems you are.
There appears to be a change of tack. Your last post reasonably restricts silicon-grease to threads only. Fair enough, we're getting there. Thus not in contact with brake-fluid; thus you're correct - it won't float anywhere. No problem with that.
Which is it? And what happens when you do rebuild calipers with silicon-grease? Impart thy wisdom.
If the above means you not advocating silicon grease in contact with glycol fluid, this when rebuilding calipers? Then you're fine.
Only it seems you are.
There appears to be a change of tack. Your last post reasonably restricts silicon-grease to threads only. Fair enough, we're getting there. Thus not in contact with brake-fluid; thus you're correct - it won't float anywhere. No problem with that.
Which is it? And what happens when you do rebuild calipers with silicon-grease? Impart thy wisdom.
Last edited:
I've read in numerous places that silicone grease is used when rebuilding calipers.
For example, numerous automotive repair textbooks say things like this:
But don't take my word for it. Go to http://books.google.com and search for caliper piston silicone grease
Last edited:
- Joined
- Oct 7, 2013
- Messages
- 104
Then it's plain wrong, yet most will live. Red brake-grease (vegetable base) is the correct item for contact with glycol-base brake-fluid. Car-culture seems to breed many myths, and those around brakes seem the most numerous. It's not hard to find falsehoods that seem to feed themselves. It's what the internet does best.
I'm off to add one of those fan doo-dads to my intake. Says here it'll give me 700 more bhp; women will drag me out at the lights and beg for sex. Problem is, after I painted my calipers red, that's already happening. What to do eh?
I'm off to add one of those fan doo-dads to my intake. Says here it'll give me 700 more bhp; women will drag me out at the lights and beg for sex. Problem is, after I painted my calipers red, that's already happening. What to do eh?
Last edited:
You are 100% correct. Thousands of cylinders and calipers have been rebuilt using silicone grease as assembly lube, in fact, it is sometimes included by the manufacturers in the kits. But let’s disregard all that and believe some guy in the internet who claims that it’s “plain wrong”.
Over the years, I have changed over many brake systems to DOT 5. How? I suck as much of the fluid out of the M/C as possible, fill it with DOT 5, and bleed til I see solid purple at each wheel. Done. Never a problem. No brake failures, no spontaneous combustion, no Fed raids on my house, nothing.
Everything I've read says that silicone grease is very inert and is used for precisely that reason. EDIT: It's commonly used to seal laboratory glassware, again because it's a very inert grease.
- Joined
- Oct 7, 2013
- Messages
- 104
This calls for that rare thing on the internet. Humble-pie. Seems whilst it's usual to run red veggie base grease in fluid - ask for brake-gease and that'll be what you'd usually get. However... it's NOT exclusive. Silicon can be used. eg: Brembo for one, supply sachets of silicon for rebuilds. In short, you can use both - and both with glycol.
www.bremboparts.com
You think you have a basic understanding of the world, then you see Twinkies are back, and nothing makes sense anymore.
Repair kit for brake calipers - Brembo
Brembo offers spare parts professionals a choice of 4 families of kits, comprising caliper components most subject to wear and deterioration.
www.bremboparts.com
You think you have a basic understanding of the world, then you see Twinkies are back, and nothing makes sense anymore.
Last edited:
I must be slow, but thanks for posting the website for speedbleeder! I knew one-person bleeders were out there but I didn't know they had this type of check-valve! That is going to make life very easy when bleeding the brakes, no more getting a 2nd person to help. Wanted to say thanks for posting this.. Best news I've had all day!
- Joined
- Dec 4, 2021
- Messages
- 746
I just did 4 way pads and rotors on my daughter's 2015 Tucson. Flushed fresh fluid through all calipers with her help pumping the pedal.
To the original question: The bleeders opened fine after 128,000 miles. The bleeder threads are now lubricated with Valvoline Dot 3/4 brake fluid. Clips and pins got silglyde. Bolts got permatex blue loctite.
To the original question: The bleeders opened fine after 128,000 miles. The bleeder threads are now lubricated with Valvoline Dot 3/4 brake fluid. Clips and pins got silglyde. Bolts got permatex blue loctite.
Last edited:
Brake fluid absorbs moisture and is not a good lubricant. Unless you tightened them too much they will probably come loose in a couple of years depending on location. Snug is the word when tightening bleed screws.
- Joined
- Oct 28, 2014
- Messages
- 1,187
That's what this site is all about! I feel as if I owe a debt of gratitude to Trav, clinebarger, the critic, Overkill, Molakule, dnewton3, and many others on this site whom I've learned much from, and yet, I'm a neophyte. All I really want to do (mechanically) is take good care of my vehicles; including my wife and daughter.I must be slow, but thanks for posting the website for speedbleeder! I knew one-person bleeders were out there but I didn't know they had this type of check-valve! That is going to make life very easy when bleeding the brakes, no more getting a 2nd person to help. Wanted to say thanks for posting this.. Best news I've had all day!
I do agree, gotta love this forum! I've learned about lots of things I didn't know or didn't know about (like these versions of speed bleeder screws). And I agree with the members you listed, their opinions/thoughts have helped me as well!That's what this site is all about! I feel as if I owe a debt of gratitude to Trav, clinebarger, the critic, Overkill, Molakule, dnewton3, and many others on this site whom I've learned much from, and yet, I'm a neophyte. All I really want to do (mechanically) is take good care of my vehicles; including my wife and daughter.
