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-   -   Remote Mount Oil Pressure Sender (https://vansairforce.net/community/showthread.php?t=99982)

rgmwa 05-22-2013 09:59 PM

Quote:

Originally Posted by rvbuilder2002 (Post 773196)
I agree.

Does the kit Lockwood supply's have a push on hose barb fittings for the hose Like the one in the photo)? :eek:

Mine is the Lockwood kit, and it comes with those barbed fittings. The fitting at the engine end has a pinhole restrictor. The hose is a push fit and secured with Oetiker clamps.

Tony_T 05-22-2013 10:50 PM

Quote:

Originally Posted by rvbuilder2002 (Post 773196)
I agree.

Does the kit Lockwood supply's have a push on hose barb fittings for the hose Like the one in the photo)? :eek:

The oil pressure sender issue goes back a couple of years at least. Many RV-12s have the Lockwood kit installed. Here is a post from a couple years ago that shows the content of the kit, including the barbed fittings and Oetiker clamps to secure the pressure hose.
I don't remember if anyone contacted Van's with the oil sender location as a problem. Since it is a Rotax part, installed by Rotax, I doubt Van's would have assumed a responsibility or provided a recommendation.

Tony

rvbuilder2002 05-23-2013 09:10 AM

Quote:

Originally Posted by Tony_T (Post 773217)
The oil pressure sender issue goes back a couple of years at least. Many RV-12s have the Lockwood kit installed. Here is a post from a couple years ago that shows the content of the kit, including the barbed fittings and Oetiker clamps to secure the pressure hose.
I don't remember if anyone contacted Van's with the oil sender location as a problem. Since it is a Rotax part, installed by Rotax, I doubt Van's would have assumed a responsibility or provided a recommendation.


I am aware of the perceived issue... I say perceived because I have never seen any level of evidence that shows that the sensor mounted on the engine has any effect on longevity.
I am aware of a few sensor failures, but there has never been any evidence to suggest that remote mounting would have prevented those failures. It seems that most of the frenzy to change the mounting location resulted from the recommendation of Lockwood. Is this because they have data they haven't shared (I have an open line of communication with a couple of the key tech. people there), or because they were searching for a solution to sensor failures and thought that sounded like a good idea?
My original question was based on a bit of surprise that the install kit uses hose barbs and clamps for a rather critical hose installation. That in it self is not bad but it does imply what type of hose is probably being used.
Personally I see this mod as attempting to cure a possible, but uncertain disease, with a potentially fatal one.
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) it induces a critical (and maybe un-necessary) hose that is highly dependent on being properly routed, restrained and protect, to prevent the hose from being compromised over time. If it ever is compromised, it will be a serious event.

JBPILOT 05-23-2013 09:48 AM

As I recall - -
 
there were 2 reasons for remotely mounting the sender. 1) The high cost of the sender, and the 'possibility' that vibration/failure was an issue. 2) The fluctuating reading on the display. The remote kit stabilizes the oil pressure readings by having a tiny port for the oil to go thru. I made my own, and used aeroquip blue hose. No problems so far.

yankee-flyer 05-23-2013 10:03 AM

Fire sleeved
 
The Lockwood kit's hose is fire sleeved. I switched locations for two reasons: As a possible way to prevent a failure, and as a cure for the continuous rapidly changing oil pressure readings. Even if I wasn't watching the Dynon the continuous fluctuation would catch my eye all the time.
The first reason may or may not have been successful-- the original sender is still working in its new location-- but the second certainly was. The pressure readings are now steady and the Dynon doesn't keep reaching out and grabbing my eye. That alone was worth the change, which I did at the first ACI.

Wayne 120241/143WM

tim2542 05-23-2013 10:56 AM

Quote:

Originally Posted by rvbuilder2002 (Post 773275)
I am aware of the perceived issue... I say perceived because I have never seen any level of evidence that shows that the sensor mounted on the engine has any effect on longevity.
.

I have zero Rotax experience, but have personally seen several cantilever mounted pressure transducers fail thru the pipe thread mounting on Diesel engines, and I believe that is the primary reason to remote mount them on aircraft. Especially on amateur built aircraft and the wide variety of components that may be used, you just don't know when something is going to resonate...or not resonate.
Tim

RFSchaller 05-23-2013 11:13 AM

Tim

I still have the engine mounted sender. You mentioned a failure of a sensor. Was it a Honeywell or one of the older types that looks like a small can? Intuitively the Honeywell seems to have a smaller moment arm and should be less susceptible.

Rich

Dave12 05-23-2013 11:15 AM

Quote:

Originally Posted by rvbuilder2002 (Post 773275)
I am aware of the perceived issue... I say perceived because I have never seen any level of evidence that shows that the sensor mounted on the engine has any effect on longevity..

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.

rvbuilder2002 05-23-2013 11:18 AM

Quote:

Originally Posted by tim2542 (Post 773314)
I have zero Rotax experience, but have personally seen several cantilever mounted pressure transducers fail thru the pipe thread mounting on Diesel engines, and I believe that is the primary reason to remote mount them on aircraft. Especially on amateur built aircraft and the wide variety of components that may be used, you just don't know when something is going to resonate...or not resonate.
Tim

I agree it is not a good practice to direct mount a sensor to a traditional aircraft engine (Cont. / Lyc.), but the 912 Rotax is a very different animal (and hugely different from a hard pounding diesel engine).

BigJohn 05-23-2013 11:27 AM

Quote:

Originally Posted by JBPILOT (Post 773290)
.....The remote kit stabilizes the oil pressure readings by having a tiny port for the oil to go thru. ......

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


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