EMERGENCY LANDING!!!!
I'm not sure if I already posted this, but it may be worth a review.
This vid is a few years old and gathering dust. I recall not really understanding what the cause of the engine stall was at the time when I made this vid. Then I forgot about the video altogether. There is some fast decision making happening here and that's the main lesson ... be ready for anything!
Turns out NOT to be the suspected fuel pump I mention in the video, but rather the old MGL fuel flow sending unit which restricted the gas through a 2mm fuel jet to supply the engine. (this was so the sending unit could function properly) This turned out to be a far to restricted fuel flow for the pump! This type of sending unit is VERY DANGEROUS and should be removed immediately if you have one installed on your trike. The new MGL red aluminum fuel flow sending unit is the replacement for this part. I had also installed the Racor 2 micron fuel filter and the Facet fuel pump depicted in the video- All of which added to the fuel flow restriction!
Funny thing was the trike work fine after this install (for quite a while I might add). It acted up on me several other times and I could not pin-point the problem cuz it was so intermittent. It wasn't like I installed the system and immediately had an issue. In fact, I had two other moments of lost power prior to this video both which resulted in emergency landings! (I may have video of those issues buried somewhere deep in the ttabs video archives as well). I even replaced the rotax fuel pump TWICE before finding out the real problem.
What was the fix? I replaced the Facet auxillary fuel pump with another identical unit but this time I located it next to the base of my fuel tank (so it wouldn't have to suck fuel up any distance to start pumping emergency fuel), I removed the 2 micron fuel filter and replaced it with a simple screen (visible type) filter, and added the new RED MGL fuel flow sending unit. I also replace all the fuel lines as well.
Lessons learned - THE OLD WHITE PLASTIC MGL FUEL FLOW SENDING UINT IS A WIDOW MAKER! If you have one, I would strongly recommend you replace it before your next flight! No need for a 2 micron filter - a screen filter works just fine. I now use a 'Mr Funnel' filter when refueling which is an absolutely awesome filter. I also carry one aboard my trike for remote fill ups. Check them out on youtube ....
Also my big lesson learned - before making random mods to your trike, CONSIDER THE POTENTIAL CONSEQUENCES. This was a real squirrelly problem that allowed me to fly over 3 different states and reared its ugly head at the most opportune times! I was LUCKY! It would fly fine for 5 or 6 flights and then BAM! I even had an engine light come on over Glacier National Park .... 40 miles from the nearest road!!!!
Food for thought during the off season.
Comments
Thanks for info Tt. I saw your video some years ago. About plastix funnel. Im using black classic plastic funnel with sifter. Plus Im putting into a filter papier when Im reuel. Im using "a big" transparent papier filter in an inclined position, to have a big surface area for fuel filtration. If in fuel is a water or smt else, it "bonding" filter under fuel level. Still the fuel level can goes up, where is next "big surface" of filter (because it is inclined).
Good landings! :)
I know that problem exactly. I followed the instructions on mine, and per instructions with the small white fuel flow meter, I added the smaller restrictor, but it didn't feel right, so I called MGL and Matt told me that it needed the larger one. It was a real booger to get the small one out, but I was able to do it. Larger restrictor was no problem. I ordered a new one when I got my new Tanarg adn I was given the Red version you mention above. Love the fuel flow meter and knowing how much fuel I'm burning real time. Thanks for the video Tom. Great job with the narration and a REALLY important topic.
Great video Tom and extremely important topic. I recall many years ago having a problem with a facet electric fuel pump that was responsible for my scariest engine out at 30 feet on takeoff. As it turns out the facet fuel pump does not permit adequate flow through the pump when not energized. Of course I was the one responsible for the problem because I had an intermittent ground issue after I had completed some rewiring work. The diaphragm pump on my carburetor was unable to pull enough fuel through the facet fuel pump when fuel demand was at its highest at wide open throttle. Needless to say I abandoned using the facet fuel pump that the previous owner of the trike had installed because the diaphragm pump was more than adequate to pull fuel up from the tank, never had that problem again. By the way in both engine out scenarios shown in the video you did a great job in putting it down where you needed to put it down. thanks for sharing.
Tom,
Was the white MGL fuel flow sender downstream of the facet fuel pump?
I have had a white MGL fuel flow sender upstream of my fuel pump for nearly 12 years and have never had a problem. The fuel is sucked past the sender at low pressure.
Jeff
Ok! I'm reading intently as I'm buying parts to do some of these mods right now. Ttabs, I've read and looked at your pictures in great detail to duplicate some of your mods and I'm so happy you posted this. I don't want to get myself in trouble here. #1 I'm confused on which Facet to buy, I run a 912 UL (80hp) that I plan to mod to a Zipper 912 (100hp) someday, I use the K&N (PN 81-0261) paper filter with the smaller opening cut off. Right now I only have the Rotax mech pump at the RGB. I would like a backup Facet pump on a switch at my dash. I will use it primarily for prime of carbs to cut back on starter turns after she's sat for a couple of weeks to a month. Yeah, yeah, my work and hanger location keep me grounded quite often! So reading this, I need what Facet, what size fittings for it, and where do I locate that sucker (also orientation? Vert or Horz flow?). I plan to skip the Racor but it's a nice piece of kit. I currently have the small white MGL fuel flow sender but I planed to just ditch the whole thing... I have the old 2006 Flycom (German) EFI on my Tanarg and it works fine so I don't have MGL avionics. Not sure if the red one will talk right to Flycom but my white one seldom does. That's mostly why I'm ditching it. Any help guys? I don't want to make it complicated or screw up my fuel restrictions. Many thanks.
The Facet pump in the video was located just past both the fuel filter and sending unit. When I disected the pump, I found it to be a very simple design and the valves inside looked to be in great shape. So I ruled out it being a problem. You can review all the facet pumps available at Aircraft Spruce :
https://www.aircraftspruce.com/catalog/eppages/facetpumps.php?clickkey=14306
In doing the fix, I believe I purchased the 40105 (your fuel pressure for Rotax should be around 2-6 psi) as it has a 12" lift and fits the window of PSI required. I ran a new fuel line out of the tank and installed the pump right there at about the same level as the base of the tank so it would be always primed. It then goes to a SCREEN type clear plastic fuel filter. I was warned not to use a paper filter. Fuel should pass from the outside in through the screen so you can see any dibris on your preflight. The type I purchased (I bought 4 of them) has a yellow large screen and I'll have to go see what type they are ... if anyone's interested.
From the filter it goes to the MGL sending unit and on to the Rotax pump. Since this little episode, I've had no issues what so ever with fuel. I deleted all the lines associated with the fuel shut off valve on the Tanarg. In other words, I have no fuel shut off valve.
And of course, I upgraded to the new Rotax fuel pump as required by Rotax.
We blamed the white MGL sending unit as the 2mm jet installed was way too restrictive. It places way too much stress on the pump.
Thanks for posting the video. As a student pilot I'm always looking for ways to be safer. I have a Facet fuel pump on order for my Airborne. My plan is to use it to prime the fuel system to make it easier to start. The Airborne is a bear to start after it has sat for a week or two. But I have found that if you prime the fuel system it fires right up. The plan is to plumb it in parallel so the engine driven pump doesn't have to pull fuel through it.
I tried that sending unit on my Geo. I haven't thought of it again until your vid. I already had a working level sender in my tank, but wanted to see consumption and use the EFIS fully. It wouldn't let the engine run above idle and never gave an accurate reading. I figured it was somthing to do with my setup. I was lucky, and found out on the ground.
Oh, and I never fill up without Mr funnel. I had a clear plastic pre pump filter that stayed completely clean for 2 years due to it. I finally replaced it and cut the filter open to inspect it, it could have stayed in service it was so clean. My second washable pre injector filter has never had anything in its screen either.
Before using Mr Funnel, I would inspect the carb bowls and discover a fine brown dust floating in the bottom. I could pick it all up with a magnetic screwdriver. It's Iron residue from fuel tanks that passed through the filters at the gas station! Since using the funnels, no iron dust what so ever.