Great Planes Adjustable Oil Pressure Regulator

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

N8053H

Well-Known Member
Joined
Jan 31, 2013
Messages
2,523
Location
Right here in front of my computer
Well I was able to get her into the air. Last evening on both attempts I lost oil pressure at the same spot halfway down the runway. This evening I was able to fly for about 5 mins. Then the oil pressure went to zero. I throttle down and within about 3 seconds the oil pressure came back up. I flew about another 5 mins and it happened again. I landed.

I think the oil level is to high. I am going to lower the oil level to the bottom mark on the stick. Do another ground run of about 45 mins. If all looks good I will fly her on a calm evening.

If it happens again after this the engine is coming off the airplane.

Tony
 

N8053H

Well-Known Member
Joined
Jan 31, 2013
Messages
2,523
Location
Right here in front of my computer
I found that the oil level needs to be between the two marks on the dipstick. Anything higher and the oil must be foaming and causing the oil pressure fluctuation and dropping of pressure. Before the upgrade I always kept the oil level at the top mark. If I raise the level to the top mark, I start having problems. Lower the level and she works fine. I did this a couple times with the same results.

I learned a lot from this. The engine will determine what oil level to use. A stroked engine will use a little less oil to fill it then a stock engine.

Interesting.

Tony
 

akwrencher

Well-Known Member
HBA Supporter
Joined
Oct 16, 2012
Messages
1,167
Location
Gustavus, AK
I'm so glad you got it figured out! These long frustrating experiences often teach us some great lessons, but it can be a whole lot of not fun-ness getting there........
 

Tuneturkey

Well-Known Member
HBA Supporter
Joined
Dec 29, 2018
Messages
64
Location
baton Rouge, LA 70816
Great discussion!
On a full case 1/2VW, the oil cooler is removed and in my case, the interface plate over the ports on the case is 1/2" alum that has a channel routed between the two case ports. In this configuration, the relief valve is almost non functioning since the oil gets to the main gallery in either case. So my question is why leave the diverter oil relief valve (prop end) in the case?
With the prop end relief orifice to the oil sump plugged, and the spring and piston removed, the flywheel end relief valve still functions regulating pressure, and the full flow of the pump goes to the main oil gallery.
All comments welcome

Johnc
 

Dana

Super Moderator
Staff member
Joined
Apr 3, 2007
Messages
9,118
Location
CT, USA
Tuneturkey, it may have been a great discussion but it's over four years old. It's usually better to start a new thread unless you're adding a followup relevant to the original discussion.
 

Tuneturkey

Well-Known Member
HBA Supporter
Joined
Dec 29, 2018
Messages
64
Location
baton Rouge, LA 70816
Tuneturkey, it may have been a great discussion but it's over four years old. It's usually better to start a new thread unless you're adding a followup relevant to the original discussion.
Dana - i understand, but have not found a post that addresses the issue of the front relief valve when no cooler is present. Is there some reason why i can't just plug the hole back to the sump, and delete the valve? if this meets the test for a new topic, then I'll re-post. Thanks.
 
Top