Any - Brake Grease Choice

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Sat 4 Jan 2020 01:35
Any - Brake Grease Choice - edlithgow

Since I don’t have time to resolve the suspected bearing failure (which may not be possible anyway) before leaving for the witer vacation, I’m stripping cleaning and re-installing the brakes.

Most of the heat is coming from here, though they may not be the underlying cause.

Passenger side doesn’t look too bad. There some black varnish-like stuff on the piston that I’d guess is derived from worn seals, but not much rust.

IMG_17314000×3000 1.86 MB

Some in the bore but only outside the seal. Cleaned up OK.

IMG_17344000×3000 2.37 MB

IMG_17353000×4000 1.73 MB

Last time I stripped them, about 4 years ago, I wrapped PTFE tape(along with silicon grease) around the caliper pins on the passenger side. This hasn’t displaced (wrapping only just visible in photo) so teflon-coated pins are easily achievable. However, just in case its sticky I took it off.

IMG_16934000×3000 1.66 MB

I’ll probably put some on the other side, and if that then sticks I’ll know not to do it again.

Since I can’t find brake grease in Taiwan (I guess Taiwanese mechanics use spit, or mineral-oil base grease which dissolves rubber) I’ve bought some in Japan and Australia, lost it and found it again, so am now a bit spoilt for choice.

IMG_17024000×3000 2.51 MB

I have 2 Japanese tubes of silicon, and used the bigger one last time. I’ve heard this has relatively low water/corrosion resistance.

1 Japanese tube of “red brakku gris”. This MAY be like the Castrol stuff.

2 Australian sachets of Bendix Ceramic. This was the most expensive and high tech, so probably doesn’t work.

What would the Old Black Hands use?

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Sat 4 Jan 2020 12:45
Any - Brake Grease Choice - Bolt

Since I don’t have time to resolve the suspected bearing failure (which may not be possible anyway) before leaving for the witer vacation, I’m stripping cleaning and re-installing the brakes.

Most of the heat is coming from here, though they may not be the underlying cause.

Passenger side doesn’t look too bad. There some black varnish-like stuff on the piston that I’d guess is derived from worn seals, but not much rust.

IMG_17314000×3000 1.86 MB

Some in the bore but only outside the seal. Cleaned up OK.

IMG_17344000×3000 2.37 MB

IMG_17353000×4000 1.73 MB

Last time I stripped them, about 4 years ago, I wrapped PTFE tape(along with silicon grease) around the caliper pins on the passenger side. This hasn’t displaced (wrapping only just visible in photo) so teflon-coated pins are easily achievable. However, just in case its sticky I took it off.

IMG_16934000×3000 1.66 MB

I’ll probably put some on the other side, and if that then sticks I’ll know not to do it again.

Since I can’t find brake grease in Taiwan (I guess Taiwanese mechanics use spit, or mineral-oil base grease which dissolves rubber) I’ve bought some in Japan and Australia, lost it and found it again, so am now a bit spoilt for choice.

IMG_17024000×3000 2.51 MB

I have 2 Japanese tubes of silicon, and used the bigger one last time. I’ve heard this has relatively low water/corrosion resistance.

1 Japanese tube of “red brakku gris”. This MAY be like the Castrol stuff.

2 Australian sachets of Bendix Ceramic. This was the most expensive and high tech, so probably doesn’t work.

What would the Old Black Hands use?

Maybe the Bendix grease as it states high temp metal to metal so probably be watertight as well, but thats debatable, problem is not knowing what the makeup is of the other two so would use the Bendix

really down to whether you trust it or not, but then do you reckon you could trust the others?

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Sun 5 Jan 2020 00:00
Any - Brake Grease Choice - edlithgow

Maybe the Bendix grease as it states high temp metal to metal so probably be watertight as well, but thats debatable, problem is not knowing what the makeup is of the other two so would use the Bendix

really down to whether you trust it or not, but then do you reckon you could trust the others?

Well, silicon seems to be the most general recommendation, but its permitted some corrosion over about 4 years.

Daihatsu manuals say ""rubber grease", whatever that means. I'd guess it might correspond to the red stuff.

I'd agree that "on paper" the Bendix should be best, which is why I bought it, but I've seen comment that some of these fancy ceramic greases (I think from Pertex) tend to solidify and/or swell rubber seals over time.

Re trust, with the probable exception of those made by CPC, the big state oil company, which ae not widely available for some reason, I wouldn't trust any grease of any kind that I've seen for sale in Taiwan, especially the ones with obviously fake "Made in USA" or even more obviously "Made product American" labelling. (You have to laugh)

Apart from the Bendix, the above are all Japanese so likely to be OK.

I ran out of time (stubbornly clogged bleed nipple) so only fully stripped the dragging side. The other side I just did Gordonbennet's trick of peeling back the dust boot and working some silicon in.

If I strip it later I'll probably use the Bendix on re-assembly.

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Sun 5 Jan 2020 00:13
Any - Brake Grease Choice - edlithgow

Supplementary question.

How bad does that bore look? (Third picture down)

I'm wondering if I should have spent a bit more time trying to polish the marks out.

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Sun 5 Jan 2020 07:31
Any - Brake Grease Choice - Bolt

Supplementary question.

How bad does that bore look? (Third picture down)

I'm wondering if I should have spent a bit more time trying to polish the marks out.

That picture is not clear enough to see properly inside the cylinder, but if the piston moves freely and doesn't leak fluid past the seal under pressure, which you wont know until its back together, then its obviously fine

I have seen worse that people have got away with, its just your picture is clear on the outside but not in focus in the cylinder

what are you using to clean the bore out?

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Sun 5 Jan 2020 08:57
Any - Brake Grease Choice - edlithgow

Supplementary question.

How bad does that bore look? (Third picture down)

I'm wondering if I should have spent a bit more time trying to polish the marks out.

That picture is not clear enough to see properly inside the cylinder, but if the piston moves freely and doesn't leak fluid past the seal under pressure, which you wont know until its back together, then its obviously fine

I have seen worse that people have got away with, its just your picture is clear on the outside but not in focus in the cylinder

what are you using to clean the bore out?

Yeh, when I took it my er...mental focus was on the corrosion outside the seal, and the camera focus coincided, though its an autofocus point-and-shoot so limited control anyway.

I use aluminium foil to clean things up. Works well, but here it might leave some abrasive paticles, though I think/hope I wiped it out with some tissues.

If I was being more thorough I might add some toothpaste, though that would need better post-treatment cleaning.

If I was being even more thorough I suppose I might use a liquid metal polish like Brasso or Silvo (don't think they make Allyo, Steelo or Castirono AFAIK) but I dont think I've ever been that thorough.

Maybe once on a piston crown, a very long time ago.

With scrounged Brasso..

Edited by edlithgow on 05/01/2020 at 09:06

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Sun 5 Jan 2020 10:01
Any - Brake Grease Choice - Bolt

Supplementary question.

How bad does that bore look? (Third picture down)

I'm wondering if I should have spent a bit more time trying to polish the marks out.

That picture is not clear enough to see properly inside the cylinder, but if the piston moves freely and doesn't leak fluid past the seal under pressure, which you wont know until its back together, then its obviously fine

I have seen worse that people have got away with, its just your picture is clear on the outside but not in focus in the cylinder

what are you using to clean the bore out?

Yeh, when I took it my er...mental focus was on the corrosion outside the seal, and the camera focus coincided, though its an autofocus point-and-shoot so limited control anyway.

I use aluminium foil to clean things up. Works well, but here it might leave some abrasive paticles, though I think/hope I wiped it out with some tissues.

If I was being more thorough I might add some toothpaste, though that would need better post-treatment cleaning.

If I was being even more thorough I suppose I might use a liquid metal polish like Brasso or Silvo (don't think they make Allyo, Steelo or Castirono AFAIK) but I dont think I've ever been that thorough.

Maybe once on a piston crown, a very long time ago.

With scrounged Brasso..

I suppose what your meant to use and what you can are 2 different things, in that very fine emery cloth is meant to be used for calliper cleaning as the particles do not stick to the metal,

anything else will be left as an abrasive in the bore,the same as pads and shoes your not supposed to use sandpaper to clean the surface as the glass sticks to the surface and can cause loss of brakes!

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Sun 5 Jan 2020 11:36
Any - Brake Grease Choice - edlithgow

Maybe I should have cleaned it more thoroughly, but I flushed the brakes on re-fittting which might help.

As I under5stand it, emery is mostly natural aluminium oxide so maybe not so very different to whatever the foil leaves behind, though the particle size will be more controlled

Glass paper would be a lot worse.

The BIG advantage of aluminium foil in this application is that it can be crumpled and crushed to conform to surfaces, such as the dust seal groove.

In an application where a residue is acceptable (probably not inside the bore, but in the dust seal groove it should be OK) it has an anti corrosion effect, which can be enhanced by using a binder. I use vegetable oil.

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Sun 5 Jan 2020 12:28
Any - Brake Grease Choice - Bolt

Glass paper would be a lot worse.

same thing just called different/names apart from sandpaper is usually thicker/stronger backing paper, point being, the sand gets into the pores of the metal and under extreme heat glazes and causes slip between two parts which is why its not to be used on pads and shoes

My old garage never stocked it as some did use it and it caused brake problems

Not heard of anyone using foil before so its a new one on me lol, but needs must as they say ;)

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Sun 5 Jan 2020 15:04
Any - Brake Grease Choice - edlithgow

Needs must applies quite often here, because things either aren't available or I can't find them.

It doesn't apply to the use of aluminium foil for metal clean-up though.

I use the foil because, in general, I find it massively superior to the alternatives in many ways.

I suggest you try it sometime..

Re residual abrasive, I saw a post er... somewhere, probably BITOG, about a failed engine rebuild which mentioned the use of Scotchbrite as a probable cause. Apparently its been the death of many an engine,

Was trying to think if I'd used it on anything. Might well have.

Maybe that shiny piston crown long long ago.

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Sun 5 Jan 2020 17:22
Any - Brake Grease Choice - Bolt

seems to be some posts are disappearing and reappearing for some reason?

Edited by bolt on 05/01/2020 at 17:23

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Mon 6 Jan 2020 00:40
Any - Brake Grease Choice - edlithgow

seems to be some posts are disappearing and reappearing for some reason?

Yeh, I noticed that.

Thought it might be "Long Slow Wire to China Syndrome" but if you're getting it as well its probably the HJ site.

Software seems comparatively limited and a bit flakey.

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Mon 6 Jan 2020 21:16
Any - Brake Grease Choice - Bolt

Software seems comparatively limited and a bit flakey.

Like the W10 updates, last one messed up my Laptops charging, discovered last night the update had a charging eco mode to assist battery life,(according to HP) it slowed charging to allow for extended battery life

needless to say it caused battery to charge intermittently, so it looked like the charger had failed when it was being told to stop charging, similar to a car smart charging system but with software failure

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