Steve
I also have one of Bryan's upgrades. I'm not flying yet but I'm leaving the "actuator" installed and plan to control it with a control cable from the panel. In the off position that will cut off the exhaust to one of the two turbine wheels. Since I will be mostly turbo-normalizing I think it will be pretty hard to overtax the turbo.


--- On Sat, 6/21/08, Steve Brooks <cozy4pilot@gmail.com> wrote:

> From: Steve Brooks <cozy4pilot@gmail.com>
> Subject: [FlyRotary] Re: Another Turbo Bites the dust
> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> Date: Saturday, June 21, 2008, 1:20 PM
> David,
> Sorry to hear about your turbo.   Especially sorry since I
> have one also.
> As I recall though, your turbo was an 86-87, which had a
> somewhat different
> design.  When I had mine done, the core was an 89-91, which
> was about $200
> cheaper.  Bryan at BNR turbo told me that the 89-91 was
> much easier to
> upgrade was the reason.
>
> I don’t know if mine will last any longer though. 130
> hours of mostly WOT
> doesn’t really sound all that bad.  It will be
> interesting to see what went
> bad on it.  Sounds like it may be the bearings though from
> the sounds of it.
>
> Regards,
> Steve Brooks
>
>
> -----Original Message-----
> From: Rotary motors in aircraft
> [mailto:flyrotary@lancaironline.net]On
> Behalf Of David Leonard
> Sent: Friday, June 20, 2008 11:47 PM
> To: Rotary motors in aircraft
> Subject: [FlyRotary] Another Turbo Bites the dust
>
> Today I flew from San Diego to Brownville Texas to attend a
> formation flying
> clinic.  After 6 hours of WOT flight I was descending
> through 5000' (down
> from 15.5k) an just a few miles from the airport when I had
> a sudden and
> sickening drop in manifold pressure.   The engine was still
> running fine,
> and I had plenty of altitude to make the runway, so I
> continued on debating
> weather or not to flip the turbo oil shutoff switch.  I had
> grown to respect
> this turbo so much that I finally decided that I had just
> blown out a
> fitting somewhere in the intake system downstream of the
> turbo.  I even
> continued on to a low pass for show rather than just
> landing.  When I
> eventually had time to take off the cowl I was dissapointed
> to find that all
> the fitting were in place and that the compressor wheel
> turns only with
> significant resistance.
>
> So the turbo is dead, and I am out of the formation clinic
> and will have to
> decide tomorrow about flying home with a dead turbo.  Will
> maybe be able to
> take a look in the hot side and see what I see.
>
> This turbo was the TO4 hybrid with a fixed wide open waste
> gate.  It had 130
> hrs of mostly hard duty.  Sigh.
>
> --
> David Leonard
>
> Turbo Rotary RV-6 N4VY
> http://N4VY.RotaryRoster.net
> http://RotaryRoster.net