Re: BTV--- a problem

Posted by HH56 On 2011/4/20 10:09:18

Quote:

On a related subject, I am again asking for owners who have catastrophic BTV failure to contact me so I can analyze the unit and determine the reason for failure, or has teh "epidemic" subsided?



I don't know if there ever was an "epidemic" just the occasional failure. It would be nice to know the reason, but I think the vast majority here happened years ago and those units are no longer available for study. Of the two or three recent ones here that I remember, I believe you looked at one and found silicone. The other, don't remember hearing about. A third failure turned out to be a tube or hose instead of BTV. Maybe expanding the inquiry to other forums would get some results.

Doing a search for Treadle Vac failure brings up several forums with a mention. We seem to be in the majority and several of them reference us but there are reports on the Chevy forum, Olds forum, Cad forum and even a Mercury using a different model BTV than we do. Interestingly, the failures are all the same--brakes one stop, none the next and then maybe works again. The Mercury had a split membrane in the hydraulic reaction piston (which we don't use) so a second point of failure apparently. That one allowed all the fluid to be sucked out. Just doing a quick read, they don't seem to be recent failures though.

The comments other posters made on their forums are the same arguments we have here. BTV was used in lots of cars and failures are isolated incidents, poor rebuilds, etc etc. One factor might be cars that sat for a long time never had any work done on the units. Fill with fluid, car stopped, and away we go. IMHO, one disturbing thing that has surfaced seems to be that some vendors or "experts" may not be doing a good or thorough job rebuilding them. I don't see why a properly rebuilt unit should need to be returned or exchanged once, let alone more than that or ever have silicone in it. I am still of the opinion a proper rebuild should be gutted and anything original yet replaceable in the hydraulic section is changed including moving hard parts. Even to the point of sleeving the casting's seal area if one pit is found. Obviously, I'm in the minority as a kit and paint job must be considered a rebuild to some.

BTV's will probably forever be one of those areas where everyone just agrees to disagree. For those comfortable with the BTV, use it, for those not, options are available.