From: "Stephen Izett stephen.izett@gmail.com" <flyrotary@lancaironline.net>
Received-SPF: pass
 receiver=logan.com; client-ip=209.85.214.172; envelope-from=stephen.izett@gmail.com
Content-Type: text/plain;
	charset=utf-8
Content-Transfer-Encoding: quoted-printable
Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3731.400.51.1.1\))
Subject: Re: [FlyRotary] Coolant barbs
Date: Wed, 15 Mar 2023 10:38:27 +0800
References: <list-1880665@logan.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
In-Reply-To: <list-1880665@logan.com>
Message-Id: <590E02C4-5028-45BF-95C3-3E8258A4D508@gmail.com>

Hi Mark.

Thats what I have done re throttle body and heater with my Renesis.
Do you have a line from the top of rear iron(front in the aeroplane) to =
purge air from the top of the motor back to a highest point in the =
system?

I tapped and plugged the hole between the pump in and out circuits below =
to OEM thermostat, but I didn=E2=80=99t put a hole in the plug for air =
to escape from the inlet side.
Is that recommended by the experts? Perhaps I missed that advice.
When I remove a screw on cap where the original thermostat used to =
lived, and my highest point in the system there is never any air =
trapped.

For clearance with cowl I cut off the Renesis thermostat housing and =
welded a screw on cap on top and an inlet barb onto the side so the flow =
is pretty much directly inline with the pump entry in the front housing.
I have from memory a 5/8=E2=80=9D restrictor in the inlet to the pump.=20=

Basically a piece of 1=E2=80=9D aluminium tube that fits through the cap =
entry I welded on, that blocks the inlet except for 5/8=E2=80=9D holes =
drilled through both sides of the tube inline with the flow.=20

I removed that restrictor recently and the temps went up considerably, =
which I put down to the pump cavitating well below my take off RPM limit =
to 7500.

My Renesis is Series 1 and I understand the pumps are known to cavitate =
at higher rpm.=20
I=E2=80=99m thinking, by removing the thermostat and smoothing the flow =
path I've lowered the rpm of the pump cavitating.

I=E2=80=99m presently considering changing the pump to an NZ pump many =
racers use (The impeller looks similar to the US Re-medy pump).=20
Basically an improved impeller designed to reduce cavitation at high =
rpm.
I might then be able to reduce the restriction and perhaps increase the =
flow rate, which will perhaps increase cooling.

Has anyone else changed pump, used a larger pulley to slow the pump, and =
has data to share?

Cheers

Steve Izett
Flying - Glasair Super IIRG Genesis 4 Port RD1-C EC2 EM3


> On 15 Mar 2023, at 9:37 am, Mark McClure mark.mcclure.m3@gmail.com =
<flyrotary@lancaironline.net> wrote:
>=20
> Planning my coolant flow for my engine setup on test stand only. Want =
to minimize unnecessary water lines. In searching the list/rx-8 forums I =
couldn=E2=80=99t find any reason I cannot just block the in and out =
spots for the throttle body and heater cores.=20
>=20
> Will be bypassing the thermostat with center plug and hole tapped for =
air bubble. Only other line will be from radiator to expansion tank.=20
>=20
> Am I mis understanding something?
>=20
> Regards,
> Mark
>=20
>=20
> <2CD7ED4F-3167-4AD8-87D3-6B01C6CD72D9-compressed.pdf>--
> Homepage:  http://www.flyrotary.com/
> Archive and UnSub:   =
http://mail.lancaironline.net:81/lists/flyrotary/List.html