What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Emergency landing this morning

airguy

Unrepentant fanboy
Sponsor
This happened to me this morning about 7am just after sunup, I'm still processing the details in my head, but here's the short version.

I was headed out to go see some friends up north, wheels up at first crack of dawn 6am this morning, and cruising along fat dumb and happy at 9500 on VFR flight following when I noticed that my AFR (air-fuel-ratio) was quite a bit leaner than I normally run it. I tweaked my mixture a bit to get it back where it should be, but my mixture control was significantly richer than it should have been for that condition. That made me take a good long look at the engine, specifically the fuel pressure - which normally runs 40-42 psi (SDS injected engine), and it was down around 29. I watched it for a few more minutes, 28. 27, 25. Definitely slowly dropping and my low fuel pressure alarm goes off. The engine starts to stumble, the AFR indicates 18 (way too lean), so I go full rich, AFR only comes up to mid-16's and my fuel pressure continues to drop. Of course I changed tanks, changed fuel pumps, changed injector boards, all the things you are supposed to do - and it didn't do anything.

That was enough, I kicked off the autopilot and keyed the radio, declaring an emergency with Center. I had a small short grass strip TE08 at my 2 o'clock and headed for that with the engine stumbling and bumbling and started descending. I was plenty close enough and high enough to deadstick it, so I pulled the throttle back to make a no-power approach - and the engine got happy again. Throttle back in, and it's not happy - back out and I get some power - about 10 seconds of this and I realize I've got about 30%-40% partial power - and that means I have options. I can almost maintain my current cruise altitude of 9500 on that.

I called Center and advised them I will be holding altitude with the partial power I have, and will attempt to overfly my known good grass strip in order to stretch my deadstick glide ring to include 77F, Winters Tx, with a paved runway and a least a fighting chance of some type of assistance. I would not have been able to do this if I was lower down - but at 9500 it was possible to include both airports in my deadstick range - so I made the decision to press on another dozen miles and try to milk the engine that far. This is exactly why I like to cruise high - it gives you time and options when things go bad.

It worked, I got within comfortable deadstick range of 77F, advised Center of my intentions, they gave me a number to call on landing and I switched to advisory. By the time I had copied down the number and gotten back on task, with the engine still happily making partial power, I was well high and had loads of energy to dissipate. I pulled the throttle all the way off (don't need it now - and can't trust it - so it no longer exists and I'm a glider) and made a few spacing turns, got into a good position for final on 17 with a 10 knot direct cross, declared intentions on the local frequency and used flaps to manage my energy for a delicious squeaker of a landing that, of course, nobody was around to see. Engine was still running so I taxied clear and shut down by the hangars.

First call was to Center on the number they gave me, advised them I was down safe, no injuries, no damage, and would have assistance on the way shortly and thanks very much. Zero drama there.

Next call was to my wife, you can pretty much guess how that one went. Next call was for help, and within 20 minutes I had a 172 loaded with tools airborne in my direction.

So - that was fun. Long story short, the cause was tracked down to a plugged 10-micron final fuel filter between my pumps and the injectors. My 50-micron pre-pump filters were dirty but not completely plugged - and the stuff in them was like muddy lint. Cleaned those out, reassembled, engine made excellent power and fuel system was doing its original thing again - so I took off and climbed in a circle over the field (with the 172 close by watching me) to about 7500 feet on my way to higher and then pointed it home. On arrival I pulled apart the entire fuel system and flushed the tanks - and found the smoking gun - which is why I'm sharing this here for you other guys that fuel yourself.

On my 125-gallon fuel transfer tank and pump, I have a 10-micron fuel filter prior to the hose, as most of us do - but I do not (yet) have any type of protection for the hose end - it is hung on a peg and open to the air. A mud-dauber had come in and started building a nest in the open hose end, and I didn't see it this morning when I was fueling my plane in the dark at 5:30, and pumped that nest into my left wing. On draining the wing tanks I ran the fuel into a filter funnel and found a fair bit of the evidence coming out of my left sump, so the chain of events is well established.

So - a good fuel system flush, another cleaning of the filters, another load of good fuel in the plane, and it's happy again. All's well that ends well - but the message here to you guys that fuel yourself with a home-brew fuel setup - PROTECT your stuff against insects. Those little buggers can kill you dead.
 
Last edited:
Busy day. Glad you found the cause. Hate it when you solve the symptom but never knew the source.
 
Great informative post! Thanks for sharing. I never thought much about why those rubbery caps were there on the fuel nozzles at airports. Now I know.
 
Really have to question the judgement of mud daubers that would build a nest in a fuel-dispensing valve and/or hose. Must be fairly recent fuel residue, and smell. Now if they were in California, they would have seen the Prop 65 warning on the hose and stayed away.

Seriously -- I can understand pitot tubes, and fuel vent tubes that almost never get any fuel in them. But a fuel dispenser? Probably still wet from the last time it was used? Why would they want to do that?

I guess I'll be more careful looking at the end of the hose when I fuel at out-of-the-way places that don't have the rubber cap but instead stick the whole valve/dispenser in a slot on the side of the pump, like an old gas station pump.
 
Greg===just goes to show that when you know your plane and its systems, you can determine whats manageable.
Excellent job my friend.
Tom
 
Thanks for sharing. How many hours do you think you had on your 10 micron filter before it plugged up?

I also have a 10 micron filter. I cleaned it out at the annual and it also looked like fine lint, but it wasnt bad enough to cause fuel problems.
 
Great story and great outcome! Sneaky little pests, those mud daubers.

Yes, altitude is your friend...and mine. When I lost my mechanical fuel pump I was at about 5500' and made the decision to fly 25 miles back to the home drome on the boost pump. I played connect-the-dots with en route airports and other good emergency landing sites and got back without too much drama.

It's chilling to work the throttle and mixture levers and have nothing happen!
 
10 micron is really fine, perhaps a larger filter with more surface area would be prudent or a pre-filter should be installed.

A typical FI system like the Bendix or AFP uses a 74 micron in the servo with a large pre-filter from 74-125 micron before the electric pump.

If I was using a 10 micron filter it would be really large as its easily plugged, as you found out.

I also wonder why the filter doesn't have a bypass of some sort (most filter are spring loaded so they will be forced open if they clog).
 
Last edited:
10 micron is really fine, perhaps a larger filter with more surface area would be prudent or a pre-filter should be installed.

A typical FI system like the Bendix or AFP uses a 74 micron in the servo with a large pre-filter from 74-125 micron before the electric pump.

If I was using a 10 micron filter it would be really large as its easily plugged, as you found out.

I also wonder why the filter doesn't have a bypass of some sort (most filter are spring loaded so they will be forced open if they clog).

He's running (as am I) EFI, so a 10 Micron filter is very normal. Personally, I have a 150 Micron Pre-Filter in each wing root, and a large 10 Micron after the pumps. My last airplane had AFP and yes, it did use a much coarser filter, however the injection orifice in a manual fuel injection vs electronic is night and day.

I have not seen a fuel filter with a built in bypass. While I'm not opposed to the idea, I would like to know if the bypass is being utilized.

Lastly, I'd love to know how large the filter was that clogged. The one I'm using is advertised at over 60 sq inches, I have not cut one yet to check but the idea was to get as much filter area as possible.
 
I’ve read a story similar to this in the past- only it was frogs in the dispenser nozzle. They found them in their tank after the dead stick. My S.O.P. since I read that is squirting .50c worth of gas next to the fuel pump before I put the nozzle near my plane. I do this everywhere I gas up. This just solidified my decision.
 
I’ve read a story similar to this in the past- only it was frogs in the dispenser nozzle. They found them in their tank after the dead stick. My S.O.P. since I read that is squirting .50c worth of gas next to the fuel pump before I put the nozzle near my plane. I do this everywhere I gas up. This just solidified my decision.

Same here. Great story, good job on the decision-making and pilot skills!

The old expression "Airspeed is the savior, but altitude is God" comes to mind :)
 
Happy ending

Thanks for sharing the story Greg. It's always great to read them when they have a happy ending and we can all learn something from the experience.
 
Partial engine failure is so hard to resist flying to a better landing spot, that is better than the nearest adequate field.
I hope I would have resisted the temptation to overfly the nearer “good grass strip”.
Greg is an experienced and excellent operator I am sure, but I remember reading a number of accident reports of partial engine failure that had a bad outcome when nearest reasonable landing place was not used.
 
glide range

Partial engine failure is so hard to resist flying to a better landing spot, that is better than the nearest adequate field.
I hope I would have resisted the temptation to overfly the nearer “good grass strip”.
Greg is an experienced and excellent operator I am sure, but I remember reading a number of accident reports of partial engine failure that had a bad outcome when nearest reasonable landing place was not used.

If I understand what he wrote here, I think he was in gliding range of the larger airport:


... at 9500 it was possible to include both airports in my deadstick range - so I made the decision to press on another dozen miles and try to milk the engine that far. ...
 
Thanks for posting, Greg! I've noticed you seem to have more or less the same setup I'm going to have (dual SDS EFI, Tuckey tanks, etc) so this was even more interesting to me. I'll be filing this one away for future reference...
 
Orifices

On my -8 during build and hangar storage, all orifices are sealed with plastic wrap and a rubber band (also good masking for the painting).

On the flying Champ, if post flight forgets the pitot cover or cowl plugs, I've made a mistake and moved an ounce from the cup of luck to the cup of experience.
 
I have not seen a fuel filter with a built in bypass. While I'm not opposed to the idea, I would like to know if the bypass is being utilized.

Practically every filter I've seen has a relief spring to bypass a clogged filter.
 

Attachments

  • fuel filter.JPG
    fuel filter.JPG
    79.3 KB · Views: 222
Bugs and frogs are dangerous

I’ve read a story similar to this in the past- only it was frogs in the dispenser nozzle. They found them in their tank after the dead stick. My S.O.P. since I read that is squirting .50c worth of gas next to the fuel pump before I put the nozzle near my plane. I do this everywhere I gas up. This just solidified my decision.

We fished 6-8 (small) frogs out of the fuel tank of our soaring club tow plane (a Pawnee). They found the (quickly dry) warm fuel nozzle a good place to spend the day apparently. Fortunately the fuel flow restriction was noticed on the ground during run up.

You never know what might kill you .... be careful out there.

Peter
 
Thanks!

Practically every filter I've seen has a relief spring to bypass a clogged filter.

Thanks Walt! I had no idea that was a relief spring (Learn something new every day). So if I understand correctly, the fuel pressure builds up due to the clogged filter and the dark metal portion gets pushed back against the spring which allows that hole in front to be revealed...thus re-establishing fuel flow. Is that right?

Ingenious.

If this occurs, I assume that the pilot would not know it until the next condition inspection.

Thanks again.
 
Not sure if you have seen this, but

The glider club at Zephyrhills, FL (KZPH) has a tow plane, Piper Pawnee. Pilots started reporting engine stumbling at high angle of attack. Nothing could be found, on the ground. After one close-call (nearly complete engine stoppage), the airplane fuel system was examined. Inside the fuel tank, approximately 12 tree frogs were found floating around (well preserved).

The fuel farm for the club used the typical fuel nozzle, with an open end. I seems that a frog would crawl in there and be dispensed with the next load of fuel. Apparently it took at least 12 fuelings before the frogs started plugging the tank outlet screen.

Yes, nature cannot be fooled!

Ron
 
In industry, its common practice for critical filters to be equipped with internal bypasses which will open at a set "cracking pressure". A 10 micron filter is very fine as far as liquid filters go, and is prone to plugging. You might consider installing a fuel filter with internal bypass set at a specific, repeatable differential pressure and then install a differential pressure switch at, say, 75% of said cracking DP connected to an alarm in your panel.

Wouldn't surprise me if there are small filters on the market incorporating the above features ready for wiring back to the panel.
 
Good job getting down! I hate that you missed the party! Why not run 10 microns on the tanks too? Then maybe if one tank is contaminated, the other would still be usable.....Now excuse me while I go check my fuel nozzel to make sure the cap is on it! :eek:
 
Good job getting down! I hate that you missed the party! Why not run 10 microns on the tanks too? Then maybe if one tank is contaminated, the other would still be usable.....Now excuse me while I go check my fuel nozzel to make sure the cap is on it! :eek:

Pushing thru 10 microns is a lot easier than trying to suck thru 10 microns........
 
Being "Great" when it counts

This happened to me this morning about 7am just after sunup, I'm still processing the details in my head, but here's the short version.

I was headed out to go see some friends up north, wheels up at first crack of dawn 6am this morning, and cruising along fat dumb and happy at 9500 on VFR flight following when I noticed that my AFR (air-fuel-ratio) was quite a bit leaner than I normally run it. I tweaked my mixture a bit to get it back where it should be, but my mixture control was significantly richer than it should have been for that condition. That made me take a good long look at the engine, specifically the fuel pressure - which normally runs 40-42 psi (SDS injected engine), and it was down around 29. I watched it for a few more minutes, 28. 27, 25. Definitely slowly dropping and my low fuel pressure alarm goes off. The engine starts to stumble, the AFR indicates 18 (way too lean), so I go full rich, AFR only comes up to mid-16's and my fuel pressure continues to drop. Of course I changed tanks, changed fuel pumps, changed injector boards, all the things you are supposed to do - and it didn't do anything.

That was enough, I kicked off the autopilot and keyed the radio, declaring an emergency with Center. I had a small short grass strip TE08 at my 2 o'clock and headed for that with the engine stumbling and bumbling and started descending. I was plenty close enough and high enough to deadstick it, so I pulled the throttle back to make a no-power approach - and the engine got happy again. Throttle back in, and it's not happy - back out and I get some power - about 10 seconds of this and I realize I've got about 30%-40% partial power - and that means I have options. I can almost maintain my current cruise altitude of 9500 on that.

I called Center and advised them I will be holding altitude with the partial power I have, and will attempt to overfly my known good grass strip in order to stretch my deadstick glide ring to include 77F, Winters Tx, with a paved runway and a least a fighting chance of some type of assistance. I would not have been able to do this if I was lower down - but at 9500 it was possible to include both airports in my deadstick range - so I made the decision to press on another dozen miles and try to milk the engine that far. This is exactly why I like to cruise high - it gives you time and options when things go bad.

It worked, I got within comfortable deadstick range of 77F, advised Center of my intentions, they gave me a number to call on landing and I switched to advisory. By the time I had copied down the number and gotten back on task, with the engine still happily making partial power, I was well high and had loads of energy to dissipate. I pulled the throttle all the way off (don't need it now - and can't trust it - so it no longer exists and I'm a glider) and made a few spacing turns, got into a good position for final on 17 with a 10 knot direct cross, declared intentions on the local frequency and used flaps to manage my energy for a delicious squeaker of a landing that, of course, nobody was around to see. Engine was still running so I taxied clear and shut down by the hangars.

First call was to Center on the number they gave me, advised them I was down safe, no injuries, no damage, and would have assistance on the way shortly and thanks very much. Zero drama there.

Next call was to my wife, you can pretty much guess how that one went. Next call was for help, and within 20 minutes I had a 172 loaded with tools airborne in my direction.

So - that was fun. Long story short, the cause was tracked down to a plugged 10-micron final fuel filter between my pumps and the injectors. My 30-micron pre-pump filters were dirty but not completely plugged - and the stuff in them was like muddy lint. Cleaned those out, reassembled, engine made excellent power and fuel system was doing its original thing again - so I took off and climbed in a circle over the field (with the 172 close by watching me) to about 7500 feet on my way to higher and then pointed it home. On arrival I pulled apart the entire fuel system and flushed the tanks - and found the smoking gun - which is why I'm sharing this here for you other guys that fuel yourself.

On my 125-gallon fuel transfer tank and pump, I have a 10-micron fuel filter prior to the hose, as most of us do - but I do not (yet) have any type of protection for the hose end - it is hung on a peg and open to the air. A mud-dauber had come in and started building a nest in the open hose end, and I didn't see it this morning when I was fueling my plane in the dark at 5:30, and pumped that nest into my left wing. On draining the wing tanks I ran the fuel into a filter funnel and found a fair bit of the evidence coming out of my left sump, so the chain of events is well established.

So - a good fuel system flush, another cleaning of the filters, another load of good fuel in the plane, and it's happy again. All's well that ends well - but the message here to you guys that fuel yourself with a home-brew fuel setup - PROTECT your stuff against insects. Those little buggers can kill you dead.

Way to go on your handling of your emergency. Good decisions all around.
Thanks for sharing.
Daddyman
 
In industry, its common practice for critical filters to be equipped with internal bypasses which will open at a set "cracking pressure". A 10 micron filter is very fine as far as liquid filters go, and is prone to plugging. You might consider installing a fuel filter with internal bypass set at a specific, repeatable differential pressure and then install a differential pressure switch at, say, 75% of said cracking DP connected to an alarm in your panel.

Wouldn't surprise me if there are small filters on the market incorporating the above features ready for wiring back to the panel.

an interesting dilemma. I would ask Ross what size debris it takes to clog an injector. Having a relief spring only allows the debris to get to the next orifice to clog. In the OP's case, it would seem that a relief spring in the fine filter would have just allowed the debris to move forward and clog the injectors. It is also possible that the injectors could pass the fine debris passed by the coarse filter and the 10 micron caused a problem that didn't have to happen, assuming the 10 was causing the bulk of the blockage.

It would seem that larger filters or a cascading system with more layers between the coarsest to finest filter may be a better answer.

Larry
 
This happened after reading this interesting post,,

Went flying yesterday, left relatively early in the AM.
Needed fuel, so I taxied over to the self-serve,
Grounded the RV, punched in my numbers & CC,,
Turned on the pump,,

Grabbed the nozzle, extended the hose to one of my tank fillers,,

Thinking about this thread, I looked at the pump nozzle and wondered, “Am I the first fueler for the day?”
Then proceeded to unscrew the hand-tight nozzle from the nozzle body, looked at the screen (it was clean), and peered down the nozzle.

I think I will incorporate this in all of my refuels, if I suspect I am the first after a period of time. No idea what the definition of “period of time” is,
But my top-off checklist just grew by one!
 
Last edited:
never say never but it is surprising that the dirt found its way so fast to the last filter and in an amount that plugged it. do you think the filter was clean before this?
 
Congrats on a great outcome. Sounds like you made some great decisions and did some excellent aviating.

I suggest sending this story to AOPA Pilot and Flying Mag for their regular "I learned something here" columns. This is a story that anyone with a home built fuel system should hear.
 
Answers to a few of the questions raised here by others...

- Yes, I did make the choice to overfly a perfectly good grass strip runway, but I want to emphasize that I never flew beyond deadstick glide range of that runway, before I was within deadstick glide range of the paved runway I wanted to get to. From my altitude, starting at 9500 and slowly decaying to around 8900 with partial power, I was able to include BOTH airports within my deadstick range and was never outside of gliding range of a suitable airport. This was a judgement call on my part, if my engine had canned itself completely at ANY point I still had a viable runway beneath me at all times. With the engine continuing to produce partial power I elected to try to make a more airplane-friendly paved runway rather than an unknown condition grass runway that was only 2000' long and in poor light - it was just barely after sunrise and I did not have a visual on the runway, just the Dynon airport information about it - for all I knew it might not even exist anymore. Anyone that would choose differently, I promise not to criticize you for your decision. I would ask the same courtesy of mine.

- Sumping the fuel - yes, I regularly sump my tanks, but I'm usually looking for water and could very easily have missed a little muddy color in the poor light when I was fueling. It's also entirely possible the mud had not fully dissolved in the tank and spread yet - gasoline is a fairly poor solvent compared to water for soil agglomerations. At the point where I first noticed the problem, I had been airborne for about 40-45 minutes, I'll have to go check the datalog to be sure but it was roughly there. I started the flight on my right tank, and changed to my left about 25-30 minutes later, and it was maybe 15 minutes after changing tanks that the problem manifested. Of course at that point changing tanks back did not help - because both tanks feed the pumps which combine to a single final fuel filter, which was now plugged.

- The fuel filter is a 10-micron filter as recommended and supplied by Ross Farnham with SDS, fairly substantial but I don't know the cross-sectional area of the pleated design, and the fuel pumps are his fuel pump module as well. The spring bypass is something to think about and perhaps test - but I know that during this event I had both pumps operating and was still only getting 9 psi out at one point, after the filter. I don't know what the pumps are capable of pressurizing to (I shall test and find out) or whether the filter will spring bypass on its own (I shall test and find out) or needs something to act as a bypass around it. I like the idea that was offered for a pressure switch upstream of the final filter to indicate a plugged condition - I'll think more on that. The SDS and EFII32 fuel injection systems (maybe others out there too, I'm not excluding them on purpose, just unaware of them) use an automotive-style electronic injector that has a much smaller orifice than aviation-standard mechanical injection, and requires a finer filter.

- The filter that got plugged was installed new in March of this year when I converted my fuel/ignition system to the SDS product with a Bosch oxygen sensor/AFR input to the SDS programmer. At the time of the problem Saturday morning I had 105 hours on the system. My fuel pressure has remained remarkably stable all this time until Saturday morning - I have no reason to believe this was a slow oncoming chronic event - I believe it to be acute. I am very highly tuned into my engine and aircraft, being a tinkerer and gearhead at heart, and normally keep a very close eye on operating parameters. I first noticed my AFR becoming lean in flight before noticing a low fuel pressure or engine stumble, and from that point to declaring a mayday with essentially no engine power and fuel pressure less than a quarter of normal was just under 2 minutes - this was not a slowly developing situation. The first 15-20 seconds of that time period, by the way, were spent in "denial and reptile-brain mode" - that's a very real phenomenon, you can't avoid it, it will happen to you - YES YOU - and all you can really do about when it happens is take a couple deep breaths and engage your inner Gene Kranz. "Calm down people, let's not make the problem worse by guessing. Think, and work the problem!"

Oh, and one clarification - I was actually on frequency with Abilene Approach at the time, not Center as I stated earlier. I realize now thinking back on it that I called them Center when I was declaring the Mayday, and they had the good common sense to ask how they could help rather than correct my label for them - I had enough on my plate at the moment.
 
Last edited:
Greg,

First, I’m glad it worked out!

Second, Thanks for sharing your experience with detail. And answering other’s questions in detail including your mindset & decision making process.

Sincerely,
 
<reads the story, scribbles down notes>

Great story and outcome.

Have added bits of this to my notes for when I teach Primary students about ground ops, re-fueling and things to look for.
 
Glad this turned out ok Greg. Good decisions and good job getting down safely.

We specify and supply 40 micron filters on all our systems. We feel that 10 micron ones have the possibility to plug up with very fine debris quicker.

Assuming there are filters before the pumps, the debris can only come from the pumps themselves making metal. Do you note any difference in noise from the pumps when you power them up?
 
Last edited:
Glad this turned out ok Greg. Good decisions and good job getting down safely.

We specify and supply 40 micron filters on all our systems. We feel that 10 micron ones have the possibility to plug up with very fine debris quicker.

We'll need to discuss that offline, then - I'm with you that they have the possibility to plug, and it only needs to protect the injector orifice, no more than that.
 
The injectors also have very fine screens inside them as the last tier in protection.

I would think it would take a lot of metal to plug the downstream filter to this degree and would be surprised if the pump(s) wasn't noisy by now.

Let me know what you find in the downstream filter.
 
Last edited:
One of our customers had a similar situation a few years back in the P-85 (like a Rocket, with V8 power). He did see a drop in fuel pressure at WOT in flight, throttled back and landed.

He had even larger filters and noticed nothing unusual during the previous flight. Found a bunch of goo in the inlet filter. Source unknown...
 
fuel

...
He had even larger filters and noticed nothing unusual during the previous flight. Found a bunch of goo in the inlet filter. Source unknown...
Had an aviation fuel expert present at one of our chapter meetings, and it was enlightening. Definitely convinced me that you need to be very careful with your fuel supplier, whether at an airport or at the mogas pump.

I'm just glad we're not running diesel, as the challenges there are even greater, with the whole fungus issue.
 
Fuel flow is only as good as the weakest link.

I could have sworn that final filter was 10-mcron, but I could be mistaken - it's the one you supplied in the kit. I'll have to review that at the hangar.

The fuel pump module that I got from you has quite a few more hours on it, because I used it with my Bendix RSA-5 setup when my original AFP fuel pumps began causing trouble and one eventually failed. I installed your fuel pump module with the Borla regulator in August 2018 and it has 375 hours on it so far, does not make any sounds I would consider unusual. What is the normal life limit of those pumps?
 
Fuel flow is only as good as the weakest link.

I could have sworn that final filter was 10-mcron, but I could be mistaken - it's the one you supplied in the kit. I'll have to review that at the hangar.

The fuel pump module that I got from you has quite a few more hours on it, because I used it with my Bendix RSA-5 setup when my original AFP fuel pumps began causing trouble and one eventually failed. I installed your fuel pump module with the Borla regulator in August 2018 and it has 375 hours on it so far, does not make any sounds I would consider unusual. What is the normal life limit of those pumps?

We have several customers with over 2000 flight hours on these pumps and our shop car had over 5000 on its Walbro pump. Have sold something over 800 of these pumps. We recommend changing them out at 2000 hours if you have twin pumps and alternate them each flight or 1000 hours on single pumps.

Have seen one failure at about 20 hours on a local install here. I could find no issue when disassembled. Motor ran fine but did not pump any fuel.

2 other quick failures (less than 10 hours each) when the guy installed them vertically high up on the firewall with the inlet facing up. (his bad idea). The pumps were processing air and fuel which destroys them quickly.
 
2 other quick failures (less than 10 hours each) when the guy installed them vertically high up on the firewall with the inlet facing up. (his bad idea). The pumps were processing air and fuel which destroys them quickly.

Yes, I'm familiar with that - that's how I killed one of the AFP fuel pumps two years ago. I missed changing out one of the natural rubber O-rings I had on an inlet fuel filter and my E10 fuel started chewing on it and it deteriorated badly. I was starting to notice a whiff of fuel smell when first opening the cockpit, and hadn't traced it down to a source yet when I noticed the fuel pump started yowling and howling - and connected the dots. The filter was leaking air into the suction side of the pump, and the pump was not happy about that.

My original plumbing setup with the dual AFP pumps left something to be desired - and you had that beautiful dual pump module out and available by then, so it was a natural choice.
 
Nozzle cover

I have a tank with a pump and filter that I use to fuel my plane. I keep it in my garage but I never thought about something getting in the nozzle. This post has encouraged me to get some kind of cover for the nozzle.

Thanks for sharing. This post may save a life
 
Every liter of fuel that goes in to my RV8 tanks goes thru a duel filtered funnel.
I used to work for an oil Co years ago, never again!
"Mr Funnel" to the rescue:)
 
Back
Top