Inverted systems

[N15TP]

I am looking to put inverted fuel and oil in my rv-4. I have an O-320E2D. I was thinking about going with the Rotec throttle body fuel injection and christen system. I know nothing about the oil systems and have a few questions...

1. Is the 801 system all I need?
2. Is there anything I should be concerned with buying a used set up?
3. Does the engine get as good of lubrication inverted as upright? Will inverted flight cause more wear than normal flight?

Thanks, Josh

[bumper]

I went with the rotec and the raven system. It is a tight fit but works well. If you go with the vacuum pump adapter the oil pressure never drops. My oil pressure is the same inverted as upright. The raven valve is easier to install because it rotates on the bracket.
Raven states their system has stainless moving parts and the christen has steel that can rust.
Make sure you make all new hoses.

[AcroGuy]

I have an RV-3 with an O-320 Lycoming. Will a Christen or Raven system fit?

[Ironflight]

Originally Posted by AcroGuy

I have an RV-3 with an O-320 Lycoming. Will a Christen or Raven system fit?

Yes - but it wil be VERY tight. You might think of a Half-Raven...slobber pot only.

[sandifer]

Originally Posted by N15TP

I am looking to put inverted fuel and oil in my rv-4. I have an O-320E2D. I was thinking about going with the Rotec throttle body fuel injection and christen system. I know nothing about the oil systems and have a few questions...

1. Is the 801 system all I need?
2. Is there anything I should be concerned with buying a used set up?
3. Does the engine get as good of lubrication inverted as upright? Will inverted flight cause more wear than normal flight?

1) The 801 is just the basic kit including the oil separator, breather tee, and oil valve. You will also need sump kit, hoses and fittings as required by your engine model. See the Christen document linked below.

http://www.rv7factory.com/files/inverted_oil.pdf

2) As far as used setups go, if they are very old, and/or not periodically cleaned, or sat unused, oil residue can build up in the separator and slow down the movement of the sliding ball bearing valve. The ball itself can become pitted due to corrosion. This will lead to excessive oil loss. Similarly, the balls in the firewall oil valve can possibly become pitted as well, which leads to oil pressure issues. Raven sells stainless steel replacement balls for Christen systems, which will not corrode.

3) Oil pressure runs slightly lower inverted due to the additional distance associated with the inverted oil "circuit". But lubrication is fine. Every time you transition from upright to inverted oil, oil pressure will drop off significantly for a couple seconds. This is normal. As long as your system functions properly, you don't need to worry about engine issues flying inverted.