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RV-12iS Fuel Pumps?

Has anyone with an RV-12iS have issues with the electric fuel pumps?
I recently completed my RV-12iS, replaced the pumps per a recent Rotax SB (SB 19-10-11).

After that, one or both pumps have failed during trials. This is my 3erd set of pumps! And still have not completed trials.
 
They are not cheap.
Fortunately, the SB replacement was covered by ROTAX, the replacement that failed, was replaced (or will be) by Lockwood Aviation, the local ROTAX Authorized Service Center.
I did buy a new set while I waited for the warranty replacement, that one also failed, Lockwood sent me a replacement, that has been working fine so far.
I'm lucky that the Lockwood people are very friendly, receptive and easy to work with!
A
 
Wondering out loud here if you have a fuel flow problem that is burning those fuel pumps up, due to lack of fuel, and lack of cooling?

That's a lot of burnt up fuel pumps.
 
The problems with the pumps:
After a few minutes operating (doing basic engine tests) in one case, one of the pumps would still run but the pressure would be lower than acceptable, the other would run fine, pressure in the green.
In the other case, both went to that mode, both, individually had lower than acceptable pressure. If both running, the pressure was in the lower green (G3X). Tank almost full in all cases.

This happened with the plane at normal temperature, just starting the engine. At low or high RPM's. Voltage ok.
I need to ask Lockwood for the root cause analysis on this.

PS: Pumps did NOT burn up. They all still ran, but the pressure was not acceptable. With the latest set, pressure is holding good all the time (so far...)
 
PS: Pumps did NOT burn up. They all still ran, but the pressure was not acceptable. With the latest set, pressure is holding good all the time (so far...)

And, when you say good all the time - you are flying the airplane now and how many hours operation?
 
Not flying yet, I'm addressing other unrelated small issues, we have done multiple high speed tests on the runway, lifting off for a few seconds then back.

When I say "running ok all the time" it means that every-time I test the engine (2-3x per week) the pumps have been working as expected. Unlike before.
 
What do you consider acceptable fuel pressure? Rotax spec is >40.61 psi per the 912iS operator's manual.

Thanks for the info!
 
Per the VANS RV-12iS POH, page 2.6, the pressure should be:
Minimum (red line): 39.2
Caution Low Range: 39.2 - 40.6
Normal Range: 40.6 - 50.8

My failing pumps had around 35 psi (one pump)
 
I don't.
I guess I trust the sensor and the Garmin G3X.

Additionally, with the faulty pumps (both on), I could not get full power, felt like fuel starvation at high RPM's (max I could get ~3900)

With the working pumps, I get full power (~4900-5000 RPM) and the correct PSI's, so all things considered, I do see that the faulty pumps did NOT produce the pressure needed.

BTW, The Lockwood team did tell me that the pumps had issues, they have the proper bench testing and pressurizing equipment on hand.
 
I seem to recall getting access to the higher pressure electrical fuel pumps on the newer 12 IS is a bugger?

How are you accessing the pumps, now that the plane is pretty much finished being built, with all the tubing and pipe/plumbing fittings? Perhaps a few pictures on how you access it?
 
OMG, glad you asked!
It is very hard and uncomfortable! But can be done.
I'm big (and heavy) so it is even harder!
What I do is use something I got at Harbor Freight, like thick bed covers, used to protect shipment materials (called Moving Blankets), I fold these several times and place them over the sharp edges in the rear bulkhead opening. Remove both seats completely and worm myself into the back, arm in, the blankets protect my belly.

Removing the pump assembly is not that hard, re-installing it is, the support clamps are almost impossible to reattach, I used long cable ties to secure them first, otherwise it is almost impossible to attach.
Sorry, did not take any pictures!

I'm surprised no one else has reported RV-12iS fuel pump failures!
 
Armando,

You might also check the fuel filters? One of the filters is user-serviceable. The other is a finer filter and is replaceable.

Best Regards,
Eric
 
yes=I can see how that would be a major pain.
 

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Initially I suspected the filters, even got a new one (expensive), the one before the pumps (afterwards I discovered that it is pilot serviceable, very easy to clean. It was clean, not good use of money)
Also, with the good pumps, PSI's are good with either pump on, so could not be the filters.
 
Pumps for 12iS

Over 10 hours of running so far with my RV-12iS and no fuel pressure issues. Unclear why you're having a such a large discrepancy. The only thing I would suggest is to put a pressure gauge in line on pressure side of the engine and run the pumps one at time to verify the pressure sender is correct.
 
Sounds like a great idea, will need to get an appropriate pressure sensor/meter and figure out how it put it inline.

Bear in mind that Lockwood confirmed the pumps had issues (where bad), so this is not a bad sensor or clogged filter.
Also, with the bad pumps running, I could detect lack of power (see previous post), not with the good pumps.
 
Forgive me if this is a dumb question - Did you happen to check the serial numbers against the Rotax Alert Service Bulletin? Obviously (I would think) the replacement pumps should have been unaffected by the ASB.

Good luck in diagnosing this. Thank you for answering my questions!
 
The first bad pumps came as replacements for the SB Rotax put out, so yes, the SN checked ok.
The second bad pumps also had good SN's

The Rotax 912iS does not have an engine driven pump, it depends 100% on these electric (and noisy) pumps.

I guess I just had a bad batch of pumps, bad luck?

My concern is, and so I started this post, if the pumps fail, the plane becomes a glider...
 
Fuel pump failure also

Just completed RV12is at the end of July with the Rotax 912is engine. No problems during initial engine runs, then transported aircraft to airport for taxi tests and first flight. On third start at airport, noticed low fuel pressure on the main pump ~38psi indicated before engine start. Pressure increased into the normal range after start. Initial thought was battery maybe low on charge.Charged the battery before next start, and this time fuel pressure was only 20psi. Engaged the aux pump and no change in pressure, switched off the main pump, and realized the aux pump wasn’t turning at all. Toggled the aux pump switch a few times, and pump started (likely because the pressure dissipated after turning off the main fuel pump). Then turned on main pump and pressure up to about 38 psi with both running. Engine started but turning either pump off caused the fuel pressure to drop rapidly and engine started to cough unless I turned it back on. I estimate that the total run time for the pumps before this problem occurred was about 45 mins.

These pumps were installed as a replacement to the originals at the end of Jan 2020 per the service bulletin.

Returned the fuel pump assembley last week to Lockwood and they agreed that the pumps were defective and have now replaced them both under warranty.

Andrew Twemlow
N699AT
 
Andrew, sorry to hear you are going thru my same ordeal!
I was getting concerned I was the only one finding these issues :)

Coincidental and as an update to my situation, I have bad news.
Since my last post, my plane has flown a little over 2 hours, during the initial tests, I'm glad to report that it fly's great, no "heavy wing" etc. Just a pleasure to fly.

Yesterday I went to the airport to update the Gamin databases, as I'm paranoid with the pumps, I tested them, pump #2 did not bring pressure!! Number 1 was fine, multiple tests, (battery charger on), etc. No joy.

Today I return with a meter, tested the voltage on both pumps, same, 13V, swapped the connectors to see if the problem would move, Nope.

During these test, pump #2, that did turn on and made some small noise (compared to the loud, working, pump #1) stopped making any sound, now it's completely dead.

Even more coincidence, today I received an email from Lockwood Aviation reporting that the last pumps I had returned did have a problem, they did not specify what type of problem or the root cause) that they will send me repaired ones.

With today's report from Andrew, I see that I'm not the only one affected, I think Rotax needs to get involved to see what is happening!!
 
There is an alternative....

yes=I can see how that would be a major pain.

Building EAB due to ULPower 350iS engine and decided to do a different fuel system. Have to work on the mount a bit for the fuel pump, but does fit.
 

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Building EAB due to ULPower 350iS engine and decided to do a different fuel system. Have to work on the mount a bit for the fuel pump, but does fit.

Very nice fuel system. 350iS is a lot of motor for RV-12. Are you concerned about exceeding structural design limits?
 
Motor Choice

I don't think its overall performance is much more than the 912iS. In my opinion, it has been well proved in the other airframes, is lower initial and maintenance costs, is very cheap to overhaul at TBO, no 5 year rubber requirements and no gearbox to deal with. I wanted AFS in the panel anyway, so the EAB was a given. Since I was EAB anyway, it was a no brainer for me. It is not the first. I know of 2 others but they were original 12's not the iS so fuel pumps were mounted on the firewall.

Very nice fuel system. 350iS is a lot of motor for RV-12. Are you concerned about exceeding structural design limits?
 
So what was the conclusion to this fuel pump issue?
Is this a somewhat common problem?


Andrew, sorry to hear you are going thru my same ordeal!
I was getting concerned I was the only one finding these issues :)

Coincidental and as an update to my situation, I have bad news.
Since my last post, my plane has flown a little over 2 hours, during the initial tests, I'm glad to report that it fly's great, no "heavy wing" etc. Just a pleasure to fly.

Yesterday I went to the airport to update the Gamin databases, as I'm paranoid with the pumps, I tested them, pump #2 did not bring pressure!! Number 1 was fine, multiple tests, (battery charger on), etc. No joy.

Today I return with a meter, tested the voltage on both pumps, same, 13V, swapped the connectors to see if the problem would move, Nope.

During these test, pump #2, that did turn on and made some small noise (compared to the loud, working, pump #1) stopped making any sound, now it's completely dead.

Even more coincidence, today I received an email from Lockwood Aviation reporting that the last pumps I had returned did have a problem, they did not specify what type of problem or the root cause) that they will send me repaired ones.

With today's report from Andrew, I see that I'm not the only one affected, I think Rotax needs to get involved to see what is happening!!
 
Another Data Point

I am an A&P helping a RV12iS owner who had fuel pump problems. We are on our third set of fuel pumps from Lockwood. He was having low pressure and intermittent pump turning on problems. We also did the SB-00041 and that seemed to help with both issues. We have three hrs. on the new pumps and they are working good. As a side note, the leds in the switch only show switch position and not if a pump is running
 
I helped my LSRM neighbor perform the SB on a friend's SLSA by wiggling the HIC connector and it failed due to "tone" change. We detached the connector and found that one of the pins was about 1/8 inch from being seated in the connector. Pushed the pin in until seated and the pumps worked fine.

Looks like a vendor/installer problem on this one.
 
Replaced Rotax for EFII pump assembly

We went through 4 fuel pumps with 912iS engine installed in a Zenith within the first 50hrs flight time, after the 3rd pump failure I ordered the EFII pump assembly and installed this when the 4th pump failed.
Customer has been flying over 70 hours since without any issues and a experiences much quieter pumps.
Need to say that all the OEM Rotax pumps were replaced quickly by Lockwood for warranty but labor and shipping still costs my customer hundreds of dollars.
 
RV12iS Low pressure before engine start

I have not yet flown the plane. I have had the (2) pumps replaced by Rotax per the Bulletin.

Each pump only puts out ~ 22PSI individually (per Dynon screen) and about 23 PSI when running together and engine not running.

When running the engine it is a bit higher, I'm guessing due to increased voltage. Engine runs very smooth @ 4000RPM

Thoughts on what I can check and/or what is wrong ?
 
Double check that your fuel sensor is set for the 150 psi DIFFERENTIAL sensor. The fact you’re readings are about half of what they should be seems to point to sensor configuration. The fuel pressure sensor was changed from a 75 to a150 psi sensor, so if the sensor was upgraded but the sensor selection wasn’t you’ll get 50% readings.
 
Building EAB due to ULPower 350iS engine and decided to do a different fuel system. Have to work on the mount a bit for the fuel pump, but does fit.

were you able to use the 3/8" tubing for the 350IS? I am looking to possibly put the same engine in my IS RV12, and have plumbed for the Rotax (which I might not be getting)
 
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