On 23 Nov 2024, at 9:31 am, Andrew Martin andrew@martinag.com.au <flyrotary@lancaironline.net> wrote:

Steve. 

I'd guess the restriction maybe from your oil filter AN10 hose combo. The pressures we are working with in the mazda are really low compared to normal hydraulics so It's really easy to restrict flow if hose size is too small or slightly kinked. I'll check mine later but I think AN12 is the min size to use.

The OEM filter can be small as it only has to filter oil going to your rotors/bearings, most of the oil pumped goes straight back to sump unfiltered after cooling. Your system is filtering all the pumped oil so filter must be much larger to cope. These restrictions can be great enough for you to see the low pressure at your sender. Fix the cause of your restriction rather than change relief valve pressures.

Andrew

On Fri, 22 Nov 2024, 20:05 Stephen Izett stephen.izett@gmail.com, <flyrotary@lancaironline.net> wrote:

Hi people.

Thanks Andrew, you were on the money with me needing to measure the system pressures.

I’d appreciate any reflections on data others have collected.

Do these numbers for pressure drop across cooler and filter look OK?

I was concerned about the 50 psi pressure reading on the EFIS but I’m now thinking that the sensor position is not accurately reading oil pressure that is getting to the bearings etc.

I’m thinking perhaps the bearings are seeing closer to perhaps 65-70 psi given the smaller channel to the relief valve and pressure sender location.

See drawing attached.

I’m considering pulling the sump off and installing an FD relief valve (higher cracking pressure) and shimming the Pump Control Valve to provide more oil to all systems.

The current relief valve appears to be opening by just above 50 psi.

This is a Renesis Series 1 4 Port - Front Cover out via AN-10 lines to Mocal 44 Row Cooler, then into remote K&N1002 Filter before into Oil pedestal. 

I fabricated an aluminium block over the two gallery holes. The AN-10 line from the Filter enters directly over the gallery to the Eccentric etc and the smaller 1/8npt feed to the RD1C gearbox directly above the channel going straight down to the rear relief valve.

The two holes/channels are linked by a milled tunnel which from memory is smaller than the Channels themselves.

My EFIS measures Oil Pressure at the 1/8 npt port below the pedestal and read about 58psi during the tests below, only rising a few psi as rpm increases to 4000.

Once temps get to 90-100C the EFIS pressure drops to about 50psi.

Ground Test Oil Pressure (psi)  / Temps (Celsius)

 

Pres/Temp RPM 2100 3000 4000

Oil Out (front Cover)      75 / 66 85 / 67 90 /69

Post Cooler                   70 / 65 78 / 66 80 / 69

Post Filter                    68 / 65 72 / 66 75 / 69

EFIS (below pedestal)  58 / 65   59 / 66    60 / 69

 

Pres Drop RPM 2100 3000 4000

Oil Cooler 5 / 65 7 / 67 10 / 69                

Oil Filter 2 / 65 4 / 66 5 / 69