Paint Master Cylinder to prevent rusting

[jowens1126]

Im about to do my Disc brake conversion and I was wondering if anyone had any suggestions on painting the master cylinder to prevent it from becoming a giant ball of rust.

POR15 should work, but I think I would rather try something clear if thats possible.  That way it would still look like bare metal but wont rust.  Maybe theres some Eastwood stuff someone has used they would recommend.

Thanks

 

[Hemikiller]

I painted mine back in '03 with cast blast from NAPA. It still looks pretty good with minimal rusting. I'll be replacing it when I swap to the 351C next year, as it's probably time.

 

[Stanglover]

I too used "Cast Blast". It was a Plasti-Coat product, but also Dupicolor have it as well as Eastwood. Get the "Engine High Heat" version though.

Always be careful with brake fluid around paint if it's Dot 3 or 4.

Dot 4 did a great job of removing overspray paint from a spare set of tail lights I picked up. Nothing to lose, but the result was outstanding, cleaned them up like new!

Geoff.

 

[Canted 393]

I have had good luck with this if you paint it ,and it dry's before you fill with brake fluid. It works ok if its full of fluid and already some surface rust.  https://www.eastwood.com/eastwood-brake-gray-aerosol.html

 

[NOT A T5]

Over 25 years ago I got mine chromed and it's held up very well!

 

[Stanglover]

I have had good luck with this if you paint it ,and it dry's before you fill with brake fluid. It works ok if its full of fluid and already some surface rust.  https://www.eastwood.com/eastwood-brake-gray-aerosol.html

That was the Eastwood product I was thinking of, not used it, but I knew they had something similar to Cast Blast.

If it is showing signs of surface rust already, perhaps the paint was applied a bit too lightly. 

Also, before painting anything like this, it is important to thoroughly clean the part with a non-chlorinated brake cleaner and/or use (Duplicolor) Grease and Wax remover.

 

[jowens1126]

Im going to give the Eastwood stuff a try. Its going on a NEW master cylinder so hopefully theres no rust on it yet. If so, I will clean it up. I also got their Paint Prep product as well to clean it..

 

[Stanglover]

Im going to give the Eastwood stuff a try.  Its going on a NEW master cylinder so hopefully theres no rust on it yet.  If so, I will clean it up.  I also got their Paint Prep product as well to clean it..

 As I said, I've not used this particular product, but I've been very impressed with Eastwood products I have used, especially the 2k ceramic paint in the engine bay.

 I'd say a good choice!

 

[jpaz]

Just spray some hi temp satin clear on it.

 

[Mister 4x4]

OK, so what if you were stupid [like me] and never painted the MC, and now it's all [surface] rusted up?

What products and/or procedures would be recommended to resolve the surface rust without making a big mess?  I'm hoping to avoid pulling the MC off and having to bleed brakes again.  I mean, I'll do it if I have to, but I'd rather not have to... ya know?

 

[Stanglover]

Well, IF you don't want to take the M/C off and I don't blame you, I'd wire brush off as much lose stuff as possible. There are quite small brushes made that will work great for that. 

In Canada, we have a product called "Rust Converter" (spray can) by Rust Check. It works by converting rust and providing a paintable primer. I have used it numerous times with great results. If this is not available in the US, there may be a similar product you can use. Once the converter has complete dried and cured the rust, prime and paint with high heat paint. 

For bets results, pull the M/C

Geoff.

 

[jowens1126]

@Mister 4x4

If your master on the car is a rusty crusty mess, and you dont want to take it off to paint it, and I really wouldnt either, There are many ways you can go.

What I personally would do,

Go to harbor freight, get a package of brushes for a dremel tool, These are a package that have multiple brushes, maybe 4 of each 3 types. Then I would use them to brush off the surface rust. These brushes are cheaply made and will send wire flying out at near the speed of light so be prepared with some PPE. Goggles, long sleeve shirt, gloves at a minimum. Then just brush it all off. It should only take a few minutes. Then you can paint it.

Another option, use a rust converter product as a primer and paint over that. This would be like, rust buillet, POR15, etc. Then use an approved topcoat color of your choice that is compatible with the rust converter paint and Brake Fluid. I would still clean it with the dremel brushes either way so the surface is nice and smooth.

 

[Canted 393]

Mr 4x4, I used this on a brake booster to help clean up surface rust. It could be left as is, or when dry use the silver paint on top, I just spray some into a cup or bowl and touch up with a brush. If you master cylinder doesn't leak it works good.

https://www.eastwood.com/eastwood-black-rust-encapsulator-paint-over-rust.html

 

[Don C]

You might try Krud Kutter Must for Rust, I've used it and it works pretty well. You can spray it on or use a paint brush to coat it. You can paint it or leave it, it protects from rust for a while.

https://www.amazon.com/KRUD-KUTTER-32-Ounce-Trigger-Spray/dp/B000F6UHDY/ref=pd_sbs_60_t_0/139-6550616-0724123?_encoding=UTF8&pd_rd_i=B000F6UHDY&pd_rd_r=ab620ab5-10f1-4fc7-a64d-e33a7d7b24aa&pd_rd_w=wQzpN&pd_rd_wg=C97Zn&pf_rd_p=5cfcfe89-300f-47d2-b1ad-a4e27203a02a&pf_rd_r=RA8A6FWQ5HJ7BYMFC4P6&psc=1&refRID=RA8A6FWQ5HJ7BYMFC4P6

 

[mach71351c]

Dammit I didn't even think about painting the master. Glad I seen this thread.

 

[NOT A T5]

I would take it off to clean it, just to do it right!

 

[Mister 4x4]

Dammit I didn't even think about painting the master. Glad I seen this thread.

Yeah, as nice as yours is coming along, it would be a shame to see the MC starting to change colors.

I think I'm going to plan on killing two birds with one stone here - I've been tossing around the idea of rear discs, and I actually have some components inherited from my pal Jim's stash.  Since I'll have to change out the proportioning valve and open up the system for the swap anyway, I'm thinking I'll just take care of everything at that point.

Great tips though, everybody!  ::thumb::

 

[Stanglover]

Dammit I didn't even think about painting the master. Glad I seen this thread.

Yeah, as nice as yours is coming along, it would be a shame to see the MC starting to change colors.

I think I'm going to plan on killing two birds with one stone here - I've been tossing around the idea of rear discs, and I actually have some components inherited from my pal Jim's stash.  Since I'll have to change out the proportioning valve and open up the system for the swap anyway, I'm thinking I'll just take care of everything at that point.

Great tips though, everybody!  ::thumb::

 Not 100% sure, but I think you'll need a different M/C anyway, disc/disc. if you add the rear disc brakes. Excellent time to prep and paint it properly regardless.

Yes indeed, I hate to see cars at shows with rusty M/C when all the rest of the under hood has been somewhat detailed. What a let down!

Geoff.

 

[Don C]

You can use the disk/drum master cylinder by removing the residual pressure valve from the rear brake outlet in the master cylinder. I would inspect it first, though, and rebuild it, if the bore isn't rusted too badly, if you want to keep the original look. You can also eliminate future rust problems by have a brass sleeve installed.