-------------- Original message from "Ed Anderson" <eanderson@carolina.rr.com>: --------------


> Bill, I believe its because there is less load with the PSRU than with the
> automobile configuration. We use the automatic flex plate which in the
> automobile has all the damping/load of the automatic transmission fluid. The
> manual transmission flywheel probably weights close to 35 lbs, so has lots
> of inertia that slows down the engine acceleration a bit. Also, I suspect
> that some of our home made manifolds may have a bit more air leakage than
> the stock throttle body/manifold - it does not take much of an air leak at
> all to really rev the engine.
>
> I am personally aware of two incidents where a 13B was fired up without a
> prop load and the throttle got advanced. One ended up with the bearings
> melting because the engine rev faster than the oil supply could supply
> pressure. The second incident ended up with the PSRU disintegrating and
> embedding bolts in the wall of the garage - it was estimated that the engine
> hit approx 13,000 rpm.
>
> Whether you accept the rationale for the high RPMs with no load or not,
> Please do not disregard these cautions - it will rev faster than you can
> react.
>
> My 1600 idle rpm throttle setting with the prop will give me 4500 rpm
> without the prop - that's the idle setting. So you can imagine just opening
> the throttle a little bit past idle would do without load
>
> Ed A
>
>
> ----- Original Message -----
> From:
> To: "Rotary motors in aircraft"
> Sent: Tuesday, October 25, 2005 8:44 AM
> Subject: [FlyRotary] Re: Its a start!
>
>
> > Snip!
> > Running without a prop is a bit risky - overrev can happen suddenly.
> > Snip!
> >
> > I don't understand how this is true...The engine has everything attached
> > that it has when it is installed in a car. It should run fine with just
> > the
> > flywheel...adding the PSRU would be similar to turning the clutch and
> > front
> > half of the tranny...????
> >
> > Please explain.
> >
> > Bill Bradburry
> >
> >
> > --
> > Homepage: http://www.flyrotary.com/
> > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
>
>
>
> --
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