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Honeywell Rotax 912 oil pressure sensors

Dynon

Dynon

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Though we don't provide the sensors ourselves, here at Dynon we're hearing a consistent theme from customers that the newer style Honeywell oil pressure sensors that are on the ASTM'd Rotax 912s used on the RV-12 aren't very reliable (and expensive to replace).

We had a chance to ask Rotax about this issue while over at the AOPA Expo last week, and they report that they've only ever received a handful of them back under warranty, and hence Rotax doesn't believe there is a problem here. Statistically, there may not be, but it's important for Rotax to know about any problems with these sensors so they can determine fleet reliability for themselves. There is evidently a test procedure for the sensor described in the engine manual which can help identify and actual failed sensor, vs one that is perhaps not connected properly.

Rotax IS very interested in getting back actual faulty sensors, and we've been told that they can be replaced under warranty if they've actually failed in warrantable circumstances. It looks like Rotax's mechanism for support issues is through one of their authorized service centers.
 
Dynon is to be commended for its fine support of its products, they offer the best support of any item on the RV-12, please keep up the good work.

Rotax on the other hand provides no support to its largest market and if they were here in the USA to provide at least some support they would understand that their customers will not purchase their very over priced prone to failure oil pressure sender and send in the old one to a company in the USA who is not interested in helping the customer, one even charges the customer just to provide the claim form with the purchase of a new replacement part, then if you spend more money to send it back to them they say they will pass it on to Rotax somewhere in the black hole of Calcutta and you may or may not ever receive some compensation or even here from them at all.

We are required to purchase the engine as part of the kit from Van's and they are not a dealer and can not provide any support both because they do not have the dealership relationship with Rotax and because they do not have the expertise on staff to deal with the problems.

Rotax could fix a lot of this by just showing their face in the USA and providing some real customer support directly to their customers instead of hiding afraid to deal with USA customers, some day soon this poor customer service will cost them the market as several other engines are making progress and starting to cut into their market share, their poor service will be rewarded in time but for now we are stuck with Rotax until Van's is willing to try some of the other new engines.

Best regards,
Vern
 
Rotax Oil Pressure Sender!

Perhaps Rotax should look at this issue from another angle. How many Honeywell senders have been sold in the USA since they have changed over to this sender? The answer to this questions which is easily tracked will show that there is a problem. I talked to all three venders in the USA as stated in my Sticky thread and they all reported that they have seen the Honeywell senders fail. Lockwood said that they cant keep them in Stock. So they do have a problem. Next year if they Show their faces at OSH I will be happy to give them an ear full.:cool:
 
The Honeywell sensor on our engine failed after 6 hours. My CA Rotax rep., California Power Systems, told me the replacement part was backordered for ~90 days. I installed the $45 VDO unit directly on the engine. The only issues with the VDO unit are that the oil pressure now reads "in the green" but 1/2 of the true value (doesn't matter) and vibration may cause the VDO unit to fail in a few hundred hours (I have a back-up in stock.) Problem solved and it's not worth another telephone call or shipping cost. I was going to throw the honeywell unit in the trash, but out here in CA we recycle that kind of stuff as electronic waste...
 
Move the Baby back to the firewall.

GDS I would think about moving you new VDO sensor back to the firewall location. There is alot less vibration there. See my Thread at this link:

http://www.vansairforce.com/community/showthread.php?t=64145&page=2

Look for my thread posted 11-13-2010, 06:13 PM on the above link. It has all the details on how to do it and the part number for the remote location kit from Lockwood. When you put it there you will not have anymore fluctuations in your readings. :cool:
 
Sensor Relocation

Ditto, John. Were I still building, I would make relocation of the Honeywell sensor to the firewall the first order of business after inspection. Start your engine up with it in original location, note oil pressure fluctuation. Now do the relocation and note the steady "needle." I ain't an engineer but I gotta believe all that shaking on the engine isn't doing the sensor any good.

The kit pictured in John's thread is very complete and an easy install.

Jim
RV12 N233TX
 
I just saw John's "relocation" this week and ordered mine the next day. It is less than $100. His set-up looks great and he says the oil pressure on his Dynon now stays rock-solid. Now, John needs to work on moving that fuel pump as well...lol.
 
oil pressure sensor failure remote firewall VDO

Thanks, I had read your post and then couldn't find it the next time I looked for it. I'm ordering the parts to move it, looks easy.
 
Me too...

GDS said:
Thanks, I had read your post and then couldn't find it the next time I looked for it. I'm ordering the parts to move it, looks easy.
Click to expand...

I will be moving my oil sender to the firewall at the same time I install the soft-start. I have the kit to move the oil pressure sender and it should be noted that it is not RV-12 specific but the components will mostly work. The oil line and fire sleeve is almost too short to reach the location on the firewall where the fuel sender is bolted, I am going to try a right-angle fitting on the engine to direct the oil line and get a little more length. The cushion clamp that comes in the kit is way too large to clamp the sender to the firewall and there is some large firesleeve that is included that can be used as cushioning material, but a smaller clamp will still be needed. The kit is pretty pricey (a sender is not included) and one could probably make it up for less, except the oil fitting with the restrictor would be difficult to make, for me at least. As John noted in his very good write-up, here, use compressed air to aid in sliding the fire sleeve over the fuel line - it really works and would be impossible otherwise.
Tony
 
Run the soft-start wiring first...

Tony, You probably already noticed but the fuel sensor hose runs right through the same neighborhood as the soft-start harness. The soft-start will be a lot easier if done before the firesleeved oil line is hooked up.

Jim
RV12 N233TX
 
Well I moved my oil pressure sensor back to the firewall. The fitting provided by Lockwood does have a very tiny hole to restrict the flow in case of broken line. When I saw it I thought WELL on start up it is going to take longer to read oil pressure . (it is going to take awhile for the pressure in the line to build up going thru this small hole) Well on start up I was right it took much longer for the pressure reading to build up after start up.(this is especially true when the engine and oil is cool) It also takes longer to bleed the pressure reading off after shut down.

None of the above is a problem. If you change yours just be ready for very slow build up of oil pressure compared to what you where use to.

Fluctuations in readings are 100% gone.


Brad Stiefvater
Salem SD
 
Bleed that Line!

Did you think to bleed the oil line going back to the fire wall location. If not simply loosen the nut on the honeywell sender a little bit. Wrap a rag around the sender and put the whole thing in a plastic baggy, then run engine for about 15 seconds. This will bleed out any air and you may see the oil pressure come up faster. When that oil is 200 degrees Fahrenheit it will be very thin and come out the little whole pretty fast.:eek:
 
Yes I taught that should be done. I figure it will be better when I do that. Just havent done that yet. First run since installed was today. I was thinking even with bleeding the line it will be a little slower to read. I will take your advise and bleed it after a good warm up.

Thanks for the advise.

Brad
 
Brad,

John (Jetguy) talked me into it and I did bleed it. Comes up every time now and as you said, steady as a rock. One think people need to remember is not to put white plumbers tape on the sensor threads. Honeywell says it is designed to fit correctly without and will risk incorrect readings if taped.

At last! I did something before Brad did. (at least I didn't smoke it!) lol

I also assume you put a Reiff on yours because of the weather but I put one on mine because of kickback concerns in cooler weather. Haven't had any yet and the temps are a nice cozy 90deg when I start up on a 40deg morning.

Hope all is well with you. My son is waiting for his class date with ATC.
 
After Brad & Pete has such good luck getting the oil pressure to stabilize by moving the oil pressure sending unit to the firewall my readings are ROCK solid. Very nice upgrade. :D
 
Unstable oil pressure

I had the same problem most others had with unstable oil pressure. I installed the new cone, spring, and cap from Lockwood Aviation and the pressure is now rock solid. Starts out at 71 psi cold and after warmup it is 68 psi.
 
ok3 said:
I had the same problem most others had with unstable oil pressure. I installed the new cone, spring, and cap from Lockwood Aviation and the pressure is now rock solid. Starts out at 71 psi cold and after warmup it is 68 psi.
Click to expand...

68 sounds kinda high. mine runs in the high 40's low 50's when warm. Did you take the little ball out when you put the cone in?

Pete
 
Jabiru

While we're on the subject of Rotax competitors in America, I wonder how Jabiru is comming on their firewall forward. :D

Any news Katie?

Gary
 
Comments on moving the oil sender...

I moved the Honeywell oil sender back to the firewall as several of the others have done and here are my experiences:
1. You can use the kit by Lockwood but it is not RV-12 specific and there are some parts that you don't need and lacking some parts you do need. Also the oil hose is 3' long and it is almost too short. Also the kit comes with only 1 Aeroquip clamp and you need 2 of those for the firesleeve. And, a cushion clamp to fit the sender could be included in the price of this kit, for heavens sake :(!
2. I used a 90° fitting (not in the kit) at the engine to direct the hose up over the top of the engine and get a little more length as the 3' hose is a bit short. The hose barb fitting with a very small restricter hole (is furnished in the kit) is screwed into the ell.
1225585407_DPHmL-M.jpg

3. The hose can be routed over the top and on the port side of the coolant header tank then along the top radiator hose to the same location as the fuel pressure sender.
4. The oil pressure sender can be mounted in a cushion clamp using the same screw that secures the fuel sender clamp. A WDG-16 clamp (not in the kit) is slightly too big so I wrapped a little silicon aircraft tape around the sender body. The clamp holds the sender firmly but not enough to damage the plastic body of the sender.
5. I filled the oil line with engine oil using a funnel at the sender end, stuck a plug in the engine end and screwed in the sender. Then carried the assembly to the engine and installed. The oil pressure will come right up with the line full of oil instead of air.
6. The sender does not need to be grounded to work. At first I was concerned that the connection to the engine was a required ground, but it works well without grounding.
7. Special tools may be required. If you use the Oetiker clamps in the kit to secure the oil line to the barbed fittings you need a tool.
Oetiker clamp:
1150626430_HaRZv-M.jpg

Also if you want to use Aeroquip clamps on the firesleeve you need a tool to install them. The bottom tool in the photo is for Oetiker clamps, the top tool is for Aeroquip clamps.
1226009040_yiYMt-M.jpg

These tools make the job look like the rest of the stuff on the engine but you could use other types of clamps. For this one time use borrowing the tools from another EAAer makes sense.

Picture of final installation at firewall
1231993973_HBZni-M.jpg


Like the other guys have said, this is a good mod. That oil pressure sender is expensive, and now it will be in a better environment and the reading will be very steady :).

Useful references:
Installing Oetiker clamps
Installing fire sleeve
 
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After reading about the Honeywell Sensors, I thought I would go ahead and purchase the re-location kit from Lockwood's. It was delivered several days ago and I had intended to install it soon. I pulled the 12 out today to bore some new holes and just after start-up, I was watching the oil pressure read-out as it died. That sensor lasted 40 hours. It appears I waited a little too long. I will try to get it covered by warranty. Does anyone know how much the replacement Honeywell costs? BTW, I did verify that it is the sender. Where can the VDO be purchased and can it be wired using the existing wire? I seem to recall a thread covering this question, but can't lay my fingers on it.
 
I ran across this Vern, you were incorrect, Vans does not require us to buy their engine. We DO have options.
vernhendershott said:
Dynon is to be commended for its fine support of its products, they offer the best support of any item on the RV-12, please keep up the good work.
We are required to purchase the engine as part of the kit from Van's and they are not a dealer and can not provide any support both because they do not have the dealership relationship with Rotax and because they do not have the expertise on staff to deal with the problems.
Vern
Click to expand...
 
Dave12 said:
After reading about the Honeywell Sensors, I thought I would go ahead and purchase the re-location kit from Lockwood's. It was delivered several days ago and I had intended to install it soon. I pulled the 12 out today to bore some new holes and just after start-up, I was watching the oil pressure read-out as it died. That sensor lasted 40 hours. It appears I waited a little too long. I will try to get it covered by warranty. Does anyone know how much the replacement Honeywell costs? BTW, I did verify that it is the sender. Where can the VDO be purchased and can it be wired using the existing wire? I seem to recall a thread covering this question, but can't lay my fingers on it.
Click to expand...

Honeywell's are around $400. Not sure if the Dynon software supports the VDO (much cheaper and Lockwood has them) so you may want to check with them.
 
Oil Pressure, 1/8-27 NPT, 0-150 PSI $35 100411-002 This oil press xducer is available from Dynon. A small wiring change is required to make it work.
 
DonFromTX said:
I ran across this Vern, you were incorrect, Vans does not require us to buy their engine. We DO have options.
Click to expand...

If we are going ELSA we must purchase from vans. 95% thru the engine kit and has gone super. That is a ton of work for those going EAB for a different engine. Good Luck
 
you can get ratcheting oetiker plier at some plumbing supply stores, they are used on pex water lines in a house. and local clamps to since they are kind of spendy to have extras lying around.

my local plumbing place would rent it out since it is a spendy tool ($85?), it works a lot better than the modified knippers. I ended up buying one for plumbing my house anyway, but thought you guys might like to try that out if you use them.

edit, for example, here is a place you can buy the ratcheting tool and clamps:

http://www.ravenproducts.us/pex.htm#clamps
 
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Does the Honeywell sensor use ground via the casing or is it just the "floating ground" from the sensor wire?

I'm mounting the sensor remotely with the kit from Lockwood and attach it with an adel clamp. Question is do I need to ground the metal part?

Regards, Joeri.
 
Thanks John. I remembered seeing your posting but couldn't find it anymore.

I'm using the new Honeywell sensor #456180 with the connector kit.
New sensor has M10x1 threads instead of 1/8"NPT.

The previous Honeywell "died" three weeks ago. Initially fluctuating pressure readings, ending in zero readings with now and then a red cross.
 
Gagarin737 said:
The previous Honeywell "died" three weeks ago. Initially fluctuating pressure readings, ending in zero readings with now and then a red cross.
Click to expand...

How many hours did your previous sender have when it died, Joeri? I assume you had not relocated the sender to the firewall?
 
912S or 912i

Joeri,
I would need to look it up again, but I recall have been told by our Rotax parts supplier that the new M10x1 threaded one was supposed to be for the 912i engine. Now, are they different or not compatible? no idea...
 
Godo said:
Joeri,
I would need to look it up again, but I recall have been told by our Rotax parts supplier that the new M10x1 threaded one was supposed to be for the 912i engine. Now, are they different or not compatible? no idea...
Click to expand...

Both version of the engine now use it.
The running modifications S.I. located HERE has the details.
 
The sensor was not relocated and died after 35 hours. Electrical both sensors are the same. I was not able to find a barb hose connector M10x1 and had to tap the one supplied by Lockwood. I choose to relocate the sensor otherwise I had to tap the oil pump housing. To do that you need to remove the oil pump housing.

See also the Skyview installation manual page 7-37 (search for 456180).
 
It appears our Honeywell sender has given up after 185 hours. Checked pressure with a mechanical gauge and all is well. What sender is everyone switch to? Looks like the VDO Lockwood offers is as good as it gets. We are also going to relocate to the firewall. If we go with VDO, what is the correct wiring procedure ?

Thanks !
 
See page 7-41 in the Skyview installation manual and then probably call Dynon for confirmation.
 
Some more Info!

AircraftSpecialty has a nice relocation Kit, although it is not shown on their web site, but call them and they will fix you up if you want their product. If you want to use the new Rotax oil pressure sensor just tell them and they will send the proper fitting for M10x1. Here is a web link I posted with pics of the old setup in my plane and the newer setup with the Kevlico sensor on newer RV12s.:D

http://www.vansairforce.com/community/showthread.php?t=111984&highlight=oil+pressure+sensor
 
Relocation kit

Actually, the Aircraft Specialty relocation kit is on their website if you dig around a bit. Complete with pictures and you can download the instruction sheet as well: http://www.aircraftspecialty.com/rv-12.html

This kit is made just for the 12 and might be better than the Lockwood kit which is not RV12 specific.

I have the Lockwood kit on mine and you can make it work, but the Specialty kit is a later development and looks to be a better fit.
 
We have ordered the aircraft specialty kit, the firesleeve is already installed so no need for the expensive clamping tool. It does not come with a sending unit. Lockwood offers two senders. Both VDO, and one appears to have a "floating ground". Not sure what that requires. I think that it will wire straight into the existing red and wht/yellow wire that the honeywell plugged in to. Maybe just a setting change in the skyview set up. I hope.

here are the two i found with lockwood.

http://www.lockwood.aero/p-3090-0-80-psi-oil-pressure-sender-vdo-2-terminal-floating-ground.aspx


https://www.lockwood.aero/p-2560-oil-pressure-sender-0-150psi-18-27npt.aspx
 
Ten years ago I had a Searey with a VDO oil pressure sensor that died after 50 hours. Hopefully the current model is more robust.
 
Why not automotive?

Maybe a dumb question here but what is so special about the Rotax oil pressure senders? Automotive senders last a long time and just keep on ticking. Is there a great difference in the vibrations produced by an engine/prop combination as opposed to an engine/transmission?

Has anyone tried using an automotive sender? Just wondering - and want to learn.
 
I have wondered the same. I read the skyview install manual and it does recommend that the senders be placed on the firewall and not directly to the engine as in the past. This is a change in recent as our Honeywell was installed on the engine from the factory.
 
The standard RV-12 kit that we offer is for the engines with the 1/8npt threads. However, we have sent out the first two kits with the metric conversion fittings for the newer engines with metric threads.

Also, if you have an engine with NPT on the engine and are going to be using a new Metric threaded sender, we can adapt without you having to re tap the threads.

If anyone has any questions, please feel free to contact us and we are happy to answer them.

Take Care,
Steve
 
Oil pressure

We have had 2 Honeywell senders fail. First one at 35 hrs and the second at 50. Got the Lockwood kit with VDO remote firewall mount. We are coming up on 600hrs now with no problem.

Rich
120002
 
If I were going to switch to the VDO unit I would go with the 0-80PSI for better
accuracy. For $45.00 with it mounted on the firewall I think you would get your monies worth out of it.;) The current OEM pressure sensor is the third change in manufacture since the RV12s went into production. The first one was a VDO unit that was changed to the Honeywell unit which occurred around 2007. Next around 2013 Rotax changed from the Honeywell to the current sensor (manufacture unknown) which probably occurred as a result of the 912SI engine coming into service. Lot of SI parts are being used on the newer non SI engines. I moved my Honeywell sensor to the firewall in the first 50 hours of service and it's still going strong at 632 hours.:)
 
Hi
The new manufactor is Keller Winterthur Switzerland! That is the same as the 912is has. I think they are the most accurate sensors you can have.

Hello to all and have a nice swing over to the 2015

Daniel 12383
 
I've changed many Honeywell oil pressure sensors on 912S's over the years.

Mostly on Tecnam P2006T twins and one more recently on a Tecnam P2002JF.

The twins all failed to zero pressure but the single remained at 4 bar or so unless the battery master was switched off and never moved engine running or not.

Much as I love Rotax, I have to admit I whinged at them many times about the reliability issues of the oil pressure sensor.

The Tecnams use a T-piece at the oil pressure sensor port so they can run a Hobbs meter switch (also locks the doors on the twin) as well as the pressure sensor.

On the RV-12, given my distrust of the Honeywell sensor, we fitted the Tecnam T-piece and run two oil pressure sensors. One is the original one and the second a Dynon SV Kavlico sensor.

On the SV display, one sensor powers the normal 'analogue gauge' whilst the second one is in the form of a widget next to the 'gauge' which goes red, yellow and green as required.

One thing that would worry me in flight is a zero oil pressure indication and with our over the top, double sensor set up we have a better chance of knowing if it's an indication failure or a real problem.
 
RFSchaller said:
Ten years ago I had a Searey with a VDO oil pressure sensor that died after 50 hours. Hopefully the current model is more robust.
Click to expand...
Mine died today (inflight, over rough terrain - ick!) at 107 hours Hobbs, 81 tach. So long, Honeywell.
 
Dgamble said:
Mine died today (inflight, over rough terrain - ick!) at 107 hours Hobbs, 81 tach. So long, Honeywell.
Click to expand...

What kind of fuel pressure reading did you get after failure?
Any other alarms popped-up?
(Close to 100 on hobbs, want to be ready:eek:)
 
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