4WD
$50 site donor 2024
Important fact. Especially in thread roots - dealt with a huge failure when humid coastal air left salt deposits on SST flange studs. Hundreds of them had to be changed during an unplanned shut down.
Coke Can for Brake Drums
- Thread starter Ducked
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Originally Posted By: Shannow
Originally Posted By: Ducked
It might melt on boilers.
Can't use zinc on the boilers.
Even marking pens have to be low melting point metal free (and chlorine free).
I think the casing tube on marker pens is aluminium, and whenever I have to use a whiteboard (avoided whenever possible) they are always nearly all dead.
Think I might have found a use for them.
Originally Posted By: Ducked
It might melt on boilers.
Can't use zinc on the boilers.
Even marking pens have to be low melting point metal free (and chlorine free).
I think the casing tube on marker pens is aluminium, and whenever I have to use a whiteboard (avoided whenever possible) they are always nearly all dead.
Think I might have found a use for them.
Might finally be a bit of substance to back up the criticism of my brake maintenance, since I appear to have a very slight fluid leak. Due a flush and a check on brake hardware anyway.
I put this wheel cylinder back on after cleaning it up about a year and half ago. It showed some wear from the corrosion, so that's prime suspect.
Drum is mostly still grey with some light rust spotting, so its sunflower oil/aluminium treatment has held up quite well.
Lots of dust, but the hardware has only rusted significantly where I didn't apply the treatment, because I was concerned it might cause sticking, or where it was too much trouble, like on the brake shoe backing
PTFE tape used on the pivot point is still in place.
Re-treated the hardware more extensively this time. I'll rely more on grease and PTFE tape to prevent sticking.
Some sign of fluid behind the wheel cylinder dust boots, though some of that is water from washing the brakes down.
I applied pressure to the brake pedal for a few hours with rubber strapping. No leakage from the wheel cylinder, but of course it isn't moving in this static test.
I think I'll still replace it assuming I can get one. If not I'll strip-clean and refit it, perhaps adding some PTFE tape around the seals.
I put this wheel cylinder back on after cleaning it up about a year and half ago. It showed some wear from the corrosion, so that's prime suspect.
Drum is mostly still grey with some light rust spotting, so its sunflower oil/aluminium treatment has held up quite well.
Lots of dust, but the hardware has only rusted significantly where I didn't apply the treatment, because I was concerned it might cause sticking, or where it was too much trouble, like on the brake shoe backing
PTFE tape used on the pivot point is still in place.
Re-treated the hardware more extensively this time. I'll rely more on grease and PTFE tape to prevent sticking.
Some sign of fluid behind the wheel cylinder dust boots, though some of that is water from washing the brakes down.
I applied pressure to the brake pedal for a few hours with rubber strapping. No leakage from the wheel cylinder, but of course it isn't moving in this static test.
I think I'll still replace it assuming I can get one. If not I'll strip-clean and refit it, perhaps adding some PTFE tape around the seals.
How big an issue is it if the shoes are contaminated with brake fluid?
I missed a trick in not boiling them when I took them off. Can't do it now because I've treated the backs with sunflower oil, but I think I've got an old spare pair of shoes somewhere so I could put them on instead.
I missed a trick in not boiling them when I took them off. Can't do it now because I've treated the backs with sunflower oil, but I think I've got an old spare pair of shoes somewhere so I could put them on instead.
I believe it can weaken the bonding of the braking material to the shoe backing plate.
If it's a few spots you could probably clean it off. If lots of contamination just replace the shoes.
If it's a few spots you could probably clean it off. If lots of contamination just replace the shoes.
Oops. Looks like I got the wrong part.
I knew only one wheel cylinder had a bleeder, but assumed apart from that they were interchangeable.
Seems not, since one seat is a convex cone, the other, with the bleeder, is a concave cone.My fault
Only 380NT, so not too tragic if they wont swap them, but a waste of time and money.
New one
\
Old one
I knew only one wheel cylinder had a bleeder, but assumed apart from that they were interchangeable.
Seems not, since one seat is a convex cone, the other, with the bleeder, is a concave cone.My fault
Only 380NT, so not too tragic if they wont swap them, but a waste of time and money.
New one
\
Old one
You need to have bleeders on both cylinders.
The hole with the convex seat is for the brake line and the one with the concave seat is for the bleeder screw.
The bleeder must be mounted on top, so that the bubble of air in the top of the cylinder can get out. For most cars there are "left" and "right" cylinders that are mirror image of each other.
The hole with the convex seat is for the brake line and the one with the concave seat is for the bleeder screw.
The bleeder must be mounted on top, so that the bubble of air in the top of the cylinder can get out. For most cars there are "left" and "right" cylinders that are mirror image of each other.
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Originally Posted By: mk378
You need to have bleeders on both cylinders.
The hole with the convex seat is for the brake line and the one with the concave seat is for the bleeder screw.
The bleeder must be mounted on top, so that the bubble of air in the top of the cylinder can get out. For most cars there are "left" and "right" cylinders that are mirror image of each other.
I thought that too before I got this car, but it isn't the case. Perhaps it isn't clear in the photo (2-D after all) but both seats are convex cones on the original cylinder, as they are on the bleederless one I swapped for this afternoon.
Apparently fairly common on 70's and 80's cars but I missed it until now.
You need to have bleeders on both cylinders.
The hole with the convex seat is for the brake line and the one with the concave seat is for the bleeder screw.
The bleeder must be mounted on top, so that the bubble of air in the top of the cylinder can get out. For most cars there are "left" and "right" cylinders that are mirror image of each other.
I thought that too before I got this car, but it isn't the case. Perhaps it isn't clear in the photo (2-D after all) but both seats are convex cones on the original cylinder, as they are on the bleederless one I swapped for this afternoon.
Apparently fairly common on 70's and 80's cars but I missed it until now.
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There were designs where two brake lines go to one of the cylinders, it acts as a tee. One line is from the master cylinder and the other one goes to the other back wheel. That other cylinder is at the end of the line and has the bleeder which will bleed the whole rear system. This was always on trucks with a solid rear axle.
So with that system you would clearly need two different kinds of cylinder.
So with that system you would clearly need two different kinds of cylinder.
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Oops again. Assuming the writing would be the right way up, I spent quite a long time installing the wheel cylinder upside down, cursing poor quality aftermarket parts the while.
Installing it upside down was VERY DIFFICULT, but I showed a lot of grit, determination and (last but not least) stupidity,
Fortunately I didn't do too much damage.
On the right way up now. Test drive probably Wed, but the leak was very slow so it'll be a while before I know if its fixed.
Installing it upside down was VERY DIFFICULT, but I showed a lot of grit, determination and (last but not least) stupidity,
Fortunately I didn't do too much damage.
On the right way up now. Test drive probably Wed, but the leak was very slow so it'll be a while before I know if its fixed.
Originally Posted By: Shannow
Originally Posted By: Ducked
It might melt on boilers.
Can't use zinc on the boilers.
Even marking pens have to be low melting point metal free (and chlorine free).
Low melting point metals (or pigments containing them) can seep along the grain boundaries and cause failure...chlorinated compounts do Stress Corrosion Cracking in stainless.
I.E. GE and N-1000 Anti-Seize on bolting
Originally Posted By: Ducked
It might melt on boilers.
Can't use zinc on the boilers.
Even marking pens have to be low melting point metal free (and chlorine free).
Low melting point metals (or pigments containing them) can seep along the grain boundaries and cause failure...chlorinated compounts do Stress Corrosion Cracking in stainless.
I.E. GE and N-1000 Anti-Seize on bolting
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