> >> Hi All,
 > >> I was glad to see at Shady Bend that Dave Atkins is using the stock

air

 > >> pump from the RX-7 to power his vacuum instruments. He told me that
 > >> works very well and the pump is producing about 16" vacuum and he has
to
 > >> bring it down to useful 5-6". I also think if the pulley is made

larger

 > >> to slow down the RPM of the pump will be beneficial.
 > >> On the down side when the air pumps fail, they lock up.  I noticed an
 > >> air pump on 20B with electric clutch, which can help in case of pump
 > >> lock-up?
 > >> Bulent
 > >

 Jeff Spitzer wrote:
 >
 > I plan to use the stock air pump for vacuum.  My approach to the failure
 > mode is to simply isolate the belts with suitable vented covers and
 > separators.  Then if the thing seizes it busts or burns the belt with no
 > further damage.  If a belt driven access. fails and takes out the water
 > pump belt then a small emergency becomes a big one.
 >
 > Jeff Spitzer

NOW you tell me, the after I purchase an electric AI.   :-)

Dave Leonard

You should have asked or got the CD Dave. We talked about this at least a year ago
:-)

Paul Lamar
 
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