Remote Mount Oil Pressure Sender - Page 3

RFSchaller · #21 05-23-2013, 11:29 AM

I think all the sensors incorporate a pinhole orifice to snub the pressure surges.

rvbuilder2002 · #22 05-23-2013, 11:34 AM

Quote:

Originally Posted by Dave12

My original sensor lasted 40 hours mounted on the engine. My current sensor is at 170 hours mounted on the firewall. Both Honeywell.

I do agree with your thoughts on everything else, but have had very good luck so far with the relocation. It is one more hose to replace every five years.

I understand that is the case with a number of RV-12 builders, but a couple or three data points doesn't prove anything. They could have just been sensors with a manufacturing defect.

Now if you had a second one fail at low hours in the original location (low odds of a customer getting two bad ones) and then installed the third one remotely and it worked fine for many hundreds of hours, then we would have something to go on.

rvbuilder2002 · #23 05-23-2013, 11:36 AM

Quote:

Originally Posted by BigJohn

Is it possible to install a "tiny port" in line with the present sensor, just to stabilize the readings? Just asking..........

As I have mentioned in the past, I think the snubbing action gained by remote mounting the sensor is due to the hose.
All hose has some level of expansion due to pressure... some more than others.

Jetguy · #24 05-23-2013, 12:41 PM

Fact: Right now on all engine mounted oil presser sensor RV12s weather Skyview or D180 the oil pressure indication fluctuates +-8 tp 10 psi.
Fact: When the the sensor is remotely mounted to the firewall with the Lockwood kit this fluctuation goes away.
IMHO: After mine failed I did some detective work and found out there were more failures than people like to think.

If you go back and search all the postings here you can see failures of the oil sensors along with a lot of discussion as to why this was occurring. Mine failed at 100 hours, now 341 hours later after moving the sensor to the fire wall, no failures. When I bought my new sensor I inquired how many they sell and the reply was we can hardly keep them in stock! If one wanted to for the purpose of this discussion call Lockword and ask I think you would be pretty surprised as to how many sensors they sell every year. At $340 per sensor I didn't mind at all paying the $70 to move mine to the fire wall. I don't think Lockwood Aviation would carry a remote mounting kit in stock if the didn't see a reason to have it. If anyone would know they would.

This is whats great about Experimental airplanes, if you perceive a problem that may cost you a reoccurring large amount of money and some one comes up with a fix for this problem than you can put the fix on your airplane if you so choose. As I have said before, " You Make the Call".

JBPILOT · #25 05-23-2013, 01:08 PM

if the remote kit did not need the tiny orifice to dampen the oil pressure fluctuations, it would not have been installed. The tiny orifice is what stabilizes the readings. The hose likely might take a little of the problem away, but not enough. Scott - 98% of the time I agree with you, so keep it up. Thanks !

RDOG · #26 05-23-2013, 02:21 PM

Quote:

Originally Posted by JBPILOT

if the remote kit did not need the tiny orifice to dampen the oil pressure fluctuations, it would not have been installed. The tiny orifice is what stabilizes the readings. The hose likely might take a little of the problem away, but not enough. Scott - 98% of the time I agree with you, so keep it up. Thanks !

I believe the tiny orifice is to preserve the oil in case of a oil line failure. You have a little time to get on the ground before you loose all of your oil if your pressure goes to zero.

GaryK · #27 05-23-2013, 02:49 PM

I built a PulsarXP back in 98 and went through 3 sensors in 125 hours. After remote mounting on the firewall I put 400+ hours on it without a problem.

I can say for sure remote mounting made a huge difference.

Building a Just Highlander now and will definitely remote mount the oil pressure sensor.

Gary

JBPILOT · #28 05-23-2013, 03:32 PM

it would help some there also, but since I built my own remote, I can tell you for absolute certain, that without the tiny orifice, the readings are not stable. I know because I had to re-do mine after finding that out.

rgmwa · #29 05-23-2013, 03:32 PM

Quote:

Originally Posted by rvbuilder2002

All of the critical hoses (oil and fuel) on the RV-12 FWF are fire sleeve protected, which gives them a high level of protection against abrasion/wear through, etc. If this particular hose is not well protected (I don't know whether it is or not)...

The hose supplied in the Lockwood kit is fire sleeved.

bajapilot · #30 05-23-2013, 07:55 PM

Quote:

Originally Posted by RDOG

I believe the tiny orifice is to preserve the oil in case of a oil line failure. You have a little time to get on the ground before you loose all of your oil if your pressure goes to zero.

If I may add 2 points.
1. Lycoming and Conti have have an orifice in the oil pressure line at the engine for over 50 years from my A&P experience and it is to limit the loss of oil in the event of a line failure. Back when they used to use a stainless or copper line it wasn't unusual to find oil dripping from the cowling after landing when a line failed. It takes a long time to pump out all the oil from that orifice.

2. It's well know in the Rans (that's with an R) community that the sensors have a short life on the engine. I'm on the third in 970 hours on my 912 in an S-7S.

Bill