TR6 Brake Mast. Cyl. & Servo TR6

[tr6web]

Quick question. I've taken out the brake master cyl. and servo. Can you start the car with them out? I was going to begin the winter by rebuilding or something (Apple Hydraulics) but I love to start it every two weeks in the winter to keep things moving. Any thoughts?

 

[Stinky]

I would think you would want to plug the vacum line that goes to the servo. Once you do that, I think it will be fine to start up,.......just don't drive it LOL!

 

[tr6web]

Ah, yes. I would probably want to do that. Now, the question...with what should I plug it up with... Thanks for the advice.

 

[PeterK]

You can pickup a rubber stopper in the correct size at your local hardware store.

 

[tr6web]

Thanks, Peter.

 

[tr6web]

While I'm talking about the brake master and servo, any tips on taking the things apart? I have the rebuild kits. I know I'm supposed to check for scoring, etc when the master cyl is apart. Also, what does that mean? Small holes? Forgive the newbie, but I would love to try these things myself.

The reason I have these off is that brake fluid was dripping on my foot ever so slightly. Figure I might as well take the master and servo off. Any suggestions would be helpful. Thanks.

 

[Steven]

[ QUOTE ]
Quick question. I've taken out the brake master cyl. and servo. Can you start the car with them out? I was going to begin the winter by rebuilding or something (Apple Hydraulics) but I love to start it every two weeks in the winter to keep things moving. Any thoughts?

[/ QUOTE ]

It is recommended NOT to start the car to keep things moving because it aids in developing moisture inside the engine, and does nothing to help. Running the motor for less than 20 minutes ON THE MOVE, not in place is necessary for any beneficial effects.

 

[trrdster2000]

Tr6web, rebuilding the master is straight forward, a couple of things that might help are: have the right size allen wrench to take the screw out under the fluid bowl,(big=1/2 inch I think), you will need to push the plugger in to take the valve out and then all will come out easy, if the rear plugger wants to stay inside just give it a tap on a bit of wood. Now you can look down the barrel and with the light in the right place look to see if any scatches or pitted areas are present, mostly on the bottom is where the pits will be and a few scatches will always be around the front inch or so, they don't really come into play. If nothing major. by that I mean a deep hole you can feel with you finger you should be able to rebuild it. Minor inperfections can be honed out with a long two stone honer you can pick up at most auto stores that goes on the end of a drill, just don't go to fast or try to do to much as you will make it too big and use some brake fluid to help you get a smoother finish. Wash with lacquar thinner and blow it out if you can, then take some small bits of cloth and wrap them around a 1/4 inch doweling rod, no metal in here. When the cloth is clean after a few tries, that's done, oh, don't forget to clean out the fluid bowls. Lub your rubber bits and put it all back together, again lub the cylinder with brake fluid and you are ready for a beer. Most important step, cleanliness and dust free in the putting it back together part, wash you hands and use some clean paper to lay the parts on. Now did you get the couple of things I was going to tell you or go to sleep. Wayne

 

[bunzil]

I'll throw my unsolicited two cents in...there's been a lot of discussion in these forums about NOT rebuilding the old master cyls and purchasing new ones in the name of safety. Unless you are totally inept I think this is a lot of nonsense. If you get back in the car, and the pedal goes to the floor - gues what? - don't put it in gear and drive off. Aside from the obvious, if you have pedal pressure, there is very little likelihood of a catastrophic failure at speed. Perhaps the pedal will be soft, if you did the rebuild incorrectly, but you'll always manage to stop. Use common sense but go ahead and rebuild it. It beats spending $180 for a new one.

A tip: make sure you note exactly how the seal gets replaced on the one way valve. There is a tendancy to place the new seal "one rung" down on the valve and this prevents the valve from sealing when pressing on the pedal and thus there's no way you can bleed the brakes. It'll drive you nuts. The very top "ring" on the valve goes inside the rubber seal - this uppermost ring is not visible if done correctly.

Finally, VTR goes on a length about "bench bleeding" the master. I've found this is also unnecessary - install the master, fill it up, and start bleeding. It works everytime for me.

As for fluid, I've used Silicone fluid for over ten years with great results. Contrary to claims, it does absorb water somewhat, but in little contained "globs" that you can actually see. This isolation of the water helps keep the rest of the system pure and moisture free. There is no need for frequent fluid changes - I'd say it has two or three times the lifespan of regular fluid. Worth the investment IMO for street cars.

 

[tr6web]

Bunzil, I agree with you 100%. My master cyldiner has been leaking for years and I just top it up and go (with a towel under the brake!). I've seen bubbles and bubbles and never once have I had any problems. I've never even bled the system (10 years). Now that I have more time, I'll do what everyone says to do, but I think you're right. Thanks for the advice and I'm definitely going to tackle it myself.

 

[Rick O.]

[ QUOTE ]
Unless you are totally inept I think this is a lot of nonsense. This isolation of the water helps keep the rest of the system pure and moisture free. There is no need for frequent fluid changes

[/ QUOTE ]
Couldn't agree more on rebuilding your MC IF the bore is not excessively pitted (the pits will simply wear the seals out quickly and you'll be rebuilding again). As far as the DOT 5.1 silicone goes, I have to disagree that it doesn't need to be changed. Like you noted, the hydraulic system still breathes-in moisture; it simply doesn't dissolve in silicone. The result is that the absorbed water pools in low spots in your hydraulics and corrosion starts there. You have to bleed agressively to get that water out. I wouldn't go longer than 3 years without bleeding silicone.

 

[Steven]

i prefer to fix things once and then enjoy the car. For that reason plus the safety factor, I prefer to swap whole units. I've never had a problem with brake or clutch master cylinder units I've installed. Fix it once, and forget it.

 

[RobT]

I am also in the process of rebuilding the hydraulics on my TR250, and was wondering what is there to rebuild on the servo? The minor repair kit looks pretty minor indeed (a new rubber boot and air filter). Is there anything else to do on this unit while I have it out?

Rob.

 

[Rick O.]

[ QUOTE ]
Is there anything else to do on this unit while I have it out?

[/ QUOTE ]
Nope. If it still provides vacuum assist and the plastic valve the manifold hose attaches to is still holding that vacuum, the internal diaphram is in good shape. If it wasn't, I'd suggest you send it off to Partco in Ohio for an internals rebuild.