Louis L. Perley III wrote:
: they're probably the same ones as when the engines were installed. There is
: a Service Bulletin that says they should be replaced every 500 hours, but
: since I've two on this aircraft I'm not going to immediately replace them,
: they both work fine and I'm pulling enough vacuum even at 1000 RPM to keep
: things in the green arc. Just something I'll need to watch closely.

Dry vacuum pumps fail without catastrophically and without notice. If it's
been awhile, I'd might replace at least one. I'd definately add the inline
chunck-catching vacuum filter so if one goes it won't spew chunks into the system and
kill the other stuff. I'm, of course, assuming this can be done/makes sense on a
twin.

-Cory


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* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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