Chris Tromley wrote: > Chuck Hursch wrote: > > > My current system has a Thomas pump. I'm leaning strongly > > towards purchasing KTA's adjustable switch (it's big though) > > for about $80. I was also able with the help of a friend to > > come up with a muffler system that quiets the noise down to > > very acceptable levels. > > Hi Chuck, > > I'd be interested in details on your vac pump muffler. > > Chris
That's going to be a hard one, since it's an old felt filter-in-a-can muffler that my friend Bob Wheeler (who was helping me out with my car last year) had from a previous job. I just checked it and there is no brand label on it, and depending on how you hook it up, can be an input filter, or an output muffler for an oil or oil-less pump. It's a little heavy, a couple of inches in diameter and four or five inches tall, with two threaded ports, and you can unscrew the top to take the filter out. Since it was free, I couldn't complain too much. When we hooked it up to my Thomas pump via a fairly long hose, and took the old little sponge filter off the pump and put it on the exhaust port of the filter can, things were way quieter than before, and for free, it was great! I'm going to mount the can on the lower front crossmember of the Rabbit (in the engine bay). There is a hole there into the crossmember which I'll point the muffler, and hopefully the large mostly enclosed airspace will soak up most of the rest of the noise. A number of people slit the sides of the hose that comes from the exhaust port of the pump, and this seems to work fairly well in quieting the noise. I saw this on Otmar's old S-10EV, and it was significantly quieter than my setup was (same pump). I don't know how much backpressure, and consequent wear and slow pumpdown, this creates, if that's it for exhausting and a plug is on the end of the hose. Chuck Hursch Larkspur, CA www.geocites.com/nbeaa
