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Triumph TR3 - Restoring Hydraulic Reservoir

Braker, Braker...

I'm getting ready to have the master and slave cylinders rebuilt, so it's time to address the most unsightly item currently under the hood.

What's the right way to refurbish the brake/clutch fluid reservoir? My reservoir and cap are covered in a nasty black paint of some sort. It occurs to me that any paint on it will be susceptible to Dot 3 fluid spills. What about the inside? What's it like in there?

Any other tips as long as I have the hydraulic lines drained? What about braided stainless vs. rubber brake hoses?

Thanks for any "braking" news...

Bill Stagg
1961 TR3A
Bill Stagg

Bill-A belated congratulations on your "Final Fling" posting. I nominate you for the Peter Egan award for journalism excellence. The first experiences with a TR3 will always be remembered-either fondly or a nightmare. At the risk of being a heretic or wimp, my favorite season for driving is fall. The weather is either cool and clear or rainy. Top up and feeble heater make for a cozy environment.
The best way to protect your paint from dot 3 fluid is to switch to silicone. Check the Buckeye site for a long treatise on silicone fluid that dispels the myths concerning problems. Replacing all of the hydraulic components provides peace of mind and is easier in the longhaul. Forty year old pipes and hoses (I am changing to the braided type) do not inspire confidence. The resevoir (reminds me of a rubber cement can)can be refinished black(the top is not painted), but may need replacing because of rust. Stainless steel pistons for the calipers should also be considered.

Bill - I agree with Berry about the silicone fluid. Change all the rubber hoses and all the seals in all 4 wheels. All the old fluid has to be out the system. The cannister and cap can be powder coated - get in touch with Fred Thomas. He will sandblast all the old paint off first. That's the first step in doing powder coat. The exteriors will clean up nicely by shot blasting with glasss beads or resin or with sand blasting. Make sure the sand etc doesn't get inside and score the bore.

If by re-furbish, you mean re-line them, send them complete to Apple in NY or White Post in VA. When I had one of mine relined by Apple, I only sent the outer body and it came back without being honed inside to the true diameter (or they forgot). If you send the full master cylinders intact, they will also change the seals too if that's what you specify. That way they'll have to hone the ID to size. Ask about them sand blasting the exteriors back to new. I think it's included, but ask.

There is a lot about silicone in the archives here and in the TR6 files. I've used it for 14 years. If you have any leaks when you get it all back together, your paint will remain as it was before.

If you're planning to clean up around the box that holds the M/C's, remove the box and have it powder coated too. While it is away, you can sand and re-spray all the firewall where the paint was stripped.

It's easier to reassemble, fill the reservoir and "bench-bleed" the master cylinders and check for leaks if you reassemble it all on your work-bench. It will be easier to tighten any fittings etc. at this time. Change the rubber seals in the bottom of the master cylinder where one of the connections is tightened inside the bottom of the reservoir. Use a material that will withstand the fluid you plan to use.

I stayed with new rubber hoses because of concours and they have been fine for 14 years (over 78,000 miles) but I have new rubber ones which I plan to put in some day - just because.

As for silicone, one TR owner wrote on the TR6 threads that silicone fluid has a lubricating property that will prevent rust on your front steel wheel cylinders. I put in new front seals. I cleaned my front pistons 14 years ago with 2000 grit wet & dry sandpaper. Never had a need for new stainless pistons. I put complete new brake cylinder kits (bodies, pistons and seals) on the rear wheels at that time. The aluminium pistons and cylinders have never jammed or wedged because the silicone fluid seems to lubricate them and prevent corrosion of the aluminium parts. You know that white hard crusty stuff that seems to appear. Well it's never been a problem with silicone fluid. This is especially important when we park our TR's for months winter after winter - 14 for me.

If you decide on silicone fluid, pour it into the reservoir system slowly to avoid entrapping air bubbles as you pour it. Make sure finish this sometime in January and bleed the lines so you will have a couple of months to let the bubbles rise so you don't suffer from "soft pedal".

Don Elliott, 1958 TR3A
Don Elliott

Don and Berry,

Thanks so much for the advice and information. You've given me the confidence to make the jump to silicone.

Berry: Do you use braided hoses because they provide less "flex" during braking, resulting in a softer pedal, or because they are more durable? Or both?

Who sells the stainless pistons? The usual suspects?

Many thanks to you both. Expect more questions when work actually commences.


Bill Stagg

Bill-I am just changing to braided hoses on the TR6, so I can't offer a comparison. I have used the braided hose on the clutch for both cars but never noticed any difference. I just like the looks, don't care about originality, and they are more abrasion resistant. In fact, if the braided hose contacts a body part, it will wear a groove in it.
The factory caliper pistons are chrome plated steel. When the chrome pits the steel rusts and the rough surface will abrade the seal. Most likely, if your car has the original caliper pistons and has used glycol fluid which absorbs a lot of moisture, the pistons will be well pitted. You can polish the pitted area, but my experience has been that the rust will continue. If replacing the pistons,using the stainless ones should be a lifetime proposition. They are available from at least Moss&TRF and are peroidically on sale. Coupled with silicone fluid and new seals/cylinders, the hydraulic system should be trouble free for many years. Don't forget the pipes too, they may look ok on the outside but can be rusting from the inside.
Berry I'm sold on rebuilding the brake system and converting to silicone fluid. Thus far, I'm planning on:

Rebuilding the master and slave cylinders (they need it)
Replacing the wheel cylinder seals (they're fine now)
Replacing the flexible brake line hoses (let's be safe)
Rebuilding the calipers (wanna paint 'em)

To ensure I rid the system of every last drop of glycol, what cleansing fluid and techniques should I use to flush out the hard brake line pipes and wash out the above items, including reservoir? Any tips for successfully using this recommended fluid?

What the heck. It's a long winter...


Bill Stagg

When you get them all apart, I'd do what I did. But I have an air compressor. You can take all the bits and tubes to a shop or gas station which has an air compressor and blow through all the tubes and pipes and blow into all the cylinders etc. I've heard it said that as long as you get "most" of the old fluid out, there should be no problem. Some gas stations may have one of those pressure tanks that you can fill up with compessed air, take it home and use that to blow the lines clean.
Don Elliott

This thread was discussed between 12/11/2003 and 25/11/2003

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