C

Clouddancer

Well Known Member
I'm building an RV-4 with a friend. We want to have aerobatic capability including sustained inverted flight.

As fa as I know there are two inverted oil system on the market: the Christen and the Raven system. They look pretty much the same. I have seen two installations of the Christen system in an RV-4.
Do you have any experience or preferences? Which one will suit better in an RV-4?
 
Inverted system?

My buddy had a Christen in his RV-4, and I have a Raven. He switched to the Raven when he built his RV-7. The reservoir is slightly smaller with the Raven, and you don't have the extra fitting outlets in the valve assembly, but it wasn't needed. You'll find getting everything to fit is a challenge. I love the Raven since I rarely lose any oil with extended inverted flight. Hope this helps,
Bill McLean
RV-4 Slider
Daleville, AL
 
I have the Raven installed in my -7, but have isolated the Oil Valve as it was causing oil pressure to fall away, and not just doing aeros either! I don't have an injected fuel system (yet) so maintaining oil pressure in sustained inverted flight isn't an issue, however I do like a clean a/c and that's what the separator does well.

Some more knowledgable folk than me say the ball valve seats in the Raven are poor quality, and I have a friend (with a -6) who replaced it with a Christen system and has had no problems. I'll probably be putting a Christen Valve in if/when I do the fuel injection thing.
 
sjjonesnz, how did you determine the valve was causing the oil pressure issue? How did you isolate it?

I have a Raven, it seems to work well.
 
Simple trouble-shooting really. Naturally the 1st thing was looking for leaks - none, and then we simply went through the oil system making sure all the lines and filters were clear - they were, so the next thing was take bits out of the system that weren't necessary and the oil valve was the first thing. Haven't had a problem since. A couple of the more engineering minded guys around the field had a look at the valve seats and told me to get them machined - something to think about when I do the whole (sustained) inverted thing
 
Thanks for your inputs and experiences! Might be that the Raven is of minor quality, at least the price is a bit lower than that of the Christen system.
 
You must log in or register to reply here.