tr7triumph.com

Car is 1980 factory TR8 Carb.

When I push in the brake pedal, there is a continuous hissing sound. Takes a lot more pressure to stop the car (no more power for the power brakes). If car is idling when I press the brakes, RPMs go up a little when I hear the hissing sound.

Obviously there is a problem with the brake booster. I will have a helper in a few days to dig deeper (I cannot press the pedal and mess with the booster at the same time).

Is this something I can rebuild? If yes, where can I get a rebuild kit? What is involved with rebuilding a booster?

If I should not try to rebuild, where can I find an affordable brake booster replacement?

Thanks,
Rob

Don't really need a helper to dig deeper. You have a bad brake booster. I can tell you exactly what's leaking but, it won't matter much. It needs to be rebuilt.

You can find a rebuid kit on ebay or contact S&S in the UK. Probably some others also.

For $20 a year, join the TWOA. Some blowhard wrote a tech article on how to rebuild your booster in your own garage a few issues ago. Where to send the booster for replating etc.

You can also buy a rebuilt one from the two US suppliers of TR8 stuff for around $300 plus shipping two ways. But, it will be painted black instead of cad plated. I thinking it's on a exchange program, so you loose your booster for one that's maybe not so nice as a dry climate one.

Good luck with your project

TR8

Check the hose first. It could be split particularly near on one of the fittings at either end, so sucking air, & that is the sound you're hearing.

I have heard hoses sucking air a couple of times, but have not heard any his from a booster even when the diaphragm was split, although this could depend on how big the split is. A big split would probably not be noisy.

How is the thing running? It should be out of tune if one inlet is getting air after the throttle butterfly.

Hasbeen

Woody did mine and redid the cad plating. Here is the one that Woody did for my TR7:

Picture at bottom of page;
http://www.jclay.me/jclay/Big_Brakes_2.html#6

Clay

[url="http://www.jclay.me/"]My Triumph Site[/url], [url="http://www.triumphtechnical.me"]Technical Stuff[/url], [url="https://docs.google.com/folder/d/0B8MWEvqOpX3udEF4SmFQUW9RS09hbU5uNW5Wd0xrUQ/edit"]My Public Folder[/url],

Thanks for the info guys.

Would it be smart to rebuild the brake master cylinder at the same time, or should I leave it alone (if it aint broke, don't fix it).?

Rob

Get a brass sleeve installed!

http://www.applehydraulics.com/brakes.htm

Clay

[url="http://www.jclay.me/"]My Triumph Site[/url], [url="http://www.triumphtechnical.me"]Technical Stuff[/url], [url="https://docs.google.com/folder/d/0B8MWEvqOpX3udEF4SmFQUW9RS09hbU5uNW5Wd0xrUQ/edit"]My Public Folder[/url],

If it is the same as the 7 the seal between the master cyl and the servo is often the culprit, this can just about be done by undoing the bolts and pulling the cyl forward.


Kevin

Quick update.

I got the rebuild kit from S&S and rebuild the brake servo today. Everything is good again.

Thanks Peter for the advice. I did finally join the TWOA. The article on rebuilding the servo was very helpful (even if the writer was bit of a blowhard).

Rob