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Engine quit on takeoff

Flying Canuck

Well Known Member
Patron
Not that I really wanted to experience an engine failure on takeoff, or any other time, but that’s what happened this afternoon. Good ending, had lots of runway left and put it down safely.

I had just flown up to Hinton/Jasper CEC4 by way of going up the middle of the Rockies. Engine has been really rough taxiing when hot, and at low power. It was a bit rough as I pulled onto the runway. 5500’ density altitude but I went full mixture and pushed in the power for my flight home. Pretty much as soon as I pulled the nose up I had a really hard stumble with significant power loss. Immediately pulled the throttle and settled it down. It was airborne but not by much. Engine quit outright as I was stopping. Fuel pressure callouts the whole time. I managed to start it again with a bunch of fuel and a flooded start procedure. Ran terrible, good temps on #1, low on #2 and cold on #3/4. Nursed it to the apron and shut it down.

My engine builder thinks it’s the fuel servo, calibration or failure. He’s flying up tomorrow to get it fixed up, I’m settled safely in a hotel for the night. Very glad that this happened when it did, not very friendly area for off field landings.

Did I mention that the flight up was spectacular and that I nailed the landing in very sporty winds?
 
Low temps on 3/4 at the same time, wasted spark systems (most every EI) fire 1/2 & 3/4. Not sure how a servo could cause 2 cyl to quit.
 
Old fashioned magnetos and fuel injection. My mechanic thinks it’s fuel starvation, but hopefully we can get it figured out. Not looking forward to the fuel bill for his Baron, at least it’s only a 45 minute flight.
 
Not that I really wanted to experience an engine failure on takeoff, or any other time, but that’s what happened this afternoon. Good ending, had lots of runway left and put it down safely.

I had just flown up to Hinton/Jasper CEC4 by way of going up the middle of the Rockies. Engine has been really rough taxiing when hot, and at low power. It was a bit rough as I pulled onto the runway. 5500’ density altitude but I went full mixture and pushed in the power for my flight home. Pretty much as soon as I pulled the nose up I had a really hard stumble with significant power loss. Immediately pulled the throttle and settled it down. It was airborne but not by much. Engine quit outright as I was stopping. Fuel pressure callouts the whole time. I managed to start it again with a bunch of fuel and a flooded start procedure. Ran terrible, good temps on #1, low on #2 and cold on #3/4. Nursed it to the apron and shut it down.

My engine builder thinks it’s the fuel servo, calibration or failure. He’s flying up tomorrow to get it fixed up, I’m settled safely in a hotel for the night. Very glad that this happened when it did, not very friendly area for off field landings.

Did I mention that the flight up was spectacular and that I nailed the landing in very sporty winds?

Why did you takeoff mixture rich at 4000ft MSL airport? I used to be based at a 4300ft airport and always leaned for peak rpm during the run up. Not saying that’s your problem but it could be part of it.
 
I was told by my mechanic that the Bendix FI won’t deliver too much fuel and that all takeoffs should be full rich. Lean for smooth running during ground operations. Of course he told me that today so I can’t use that as an excuse for my takeoff today. It would have been one of my higher density altitude takeoffs, maybe leaned would have worked better, maybe it would have made the problem wait until I was in a pickle.
 
Why did you takeoff mixture rich at 4000ft MSL airport? I used to be based at a 4300ft airport and always leaned for peak rpm during the run up. Not saying that’s your problem but it could be part of it.

The Lycoming manual says to take off rich when you are under 5000 ft DA
 
I lived at 4,000 feet and on days like today our DA is 8K. I do a lean optimization on every run up, Summer or Winter. We can tell a pilot isn't from around here when they follow the factory check list and take off full rich. It's right up there with having 4 people in a Cessna 172 just passing through who top their tanks. Lots of those hulls down in the arroyo.

Jim
 
And I have never heard that the Bendix FI system can't run too rich and always go full rich for takeoff. That kind of advice could kill you at our airport. Maybe your mechanic was letting you down easy after a stressful day or doesn't understand the RSA fuel servo. But don't do that at high density altitudes.
 
Hindsight has a much larger field of vision than projection or speculation.

I'm grateful you shared your experience and keenly await your findings. I definitely want to learn from this!
 
Why did you takeoff mixture rich at 4000ft MSL airport? I used to be based at a 4300ft airport and always leaned for peak rpm during the run up. Not saying that’s your problem but it could be part of it.

FWIW, Im based at 6600 ft MSL. 9000 ft MSL DA is dead common in the summer. I never lean for takeoff. Got plenty of power and it helps keep CHTs below 400. Takeoff fuel flow is about 13.6 gph.
 
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Tom, I have been dealing with takeoff FF issues. Your takeoff fuel flow is probably just right for the altitude you are at but would be very low for a sea level airport. Most sources recommend you set up for sea level and lean for high altitude airports. Your engine should flow 17 to 18 GPH full rich.
G
 
Tom, I have been dealing with takeoff FF issues. Your takeoff fuel flow is probably just right for the altitude you are at but would be very low for a sea level airport. Most sources recommend you set up for sea level and lean for high altitude airports. Your engine should flow 17 to 18 GPH full rich.
G

Thank you so much for your comment on carb setup.

The majority of my takeoffs are at higher DA airports. When I do get out to the West Coast takeoff power and performance has been very impressive, but Ive been airborne so much more quickly that Ive not noticed the takeoff fuel flow. I haven’t touched the carb since buying the plane in mid-2017.

That said, last Thursday during a dawn takeoff out of Salida, CO (7500 ft MSL) the plane felt unexpectedly underpowered and only showed about 10.8 gph, which did not make for a comfortable initial climbout. EGTs were about 30-40F lower than usual. I’ve been planning to test the current takeoff fuel flow this week before flying it anywhere.
 
And I have never heard that the Bendix FI system can't run too rich and always go full rich for takeoff. That kind of advice could kill you at our airport. Maybe your mechanic was letting you down easy after a stressful day or doesn't understand the RSA fuel servo. But don't do that at high density altitudes.

Ummm....

Can't speak for Claude, but I do have some understanding the Bendix-style fuel control. It does indeed compensate for density, not perfectly, but well enough that full rich does not cause a really significant power loss, and certainly not the OP's power failure.

Consider the plot below, fuel flow plotted against standard air density while climbing from 2000 feet through 15,000 feet, running WOT, full rich, and 2700 rpm. It's my IO-390; the fuel control is an Airflow Performance FM-200. Density at 15,000 is 67% of the 2000 foot density (0.0481/0.0721), while fuel flow declines to 77% (13.7/17.8). The result is a small overall enrichment of fuel/air ratio, although it is nothing like the enrichment we would see if fuel flow remained constant.

How much richer? The answer can be derived from the mass calculations, or from exhaust gas temperature. Here the average EGT drop for the whole climb was approximately 200°F. The relationship of F/A ratio to EGT is known to be near linear in this part of the rich-of-peak operating region, so consulting Lycoming data says the ratio shift is a bit more than 0.02, here from 0.08 to roughly 0.10 F/A, or 12.5:1 to 10:1 air-fuel. A plot of peak power vs. mixture is fairly flat in this F/A range, so the power loss due to enrichment is less than 5% if the pilot does nothing. Again, that 5% assumes a 13,000 span, 2000 to 15,000 feet.

.
 

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Engine has been really rough taxiing when hot, and at low power. It was a bit rough as I pulled onto the runway. 5500’ density altitude but I went full mixture and pushed in the power for my flight home. Pretty much as soon as I pulled the nose up I had a really hard stumble with significant power loss. Immediately pulled the throttle and settled it down. It was airborne but not by much. Engine quit outright as I was stopping. Fuel pressure callouts the whole time. I managed to start it again with a bunch of fuel and a flooded start procedure. Ran terrible, good temps on #1, low on #2 and cold on #3/4. Nursed it to the apron and shut it down.

I've gotten allergic to long distance diagnosis, but if I had to call this one based on the above, I'd ask when the Bendix RSA-5's fuel inlet screen was last pulled and cleaned.

It's spring loaded to seal. It will compress the spring, raise off its seat, and allow fuel to bypass if clogged...typically at max fuel flow. When it does, some of the garbage can flush into the servo, divider, and nozzles.
 
Dan and others, thanks for your insight. After seeing the responses here and mulling over the incident most of the night I have arrived at the following.
  • Leaning at full power may have been the better choice
  • Full rich may have contributed to some power loss
  • 5500’ density altitude is high, but not Colorado high
  • I have taken off at full rich every time, even in Colorado
  • My roughness to this point was always in a low power state, taxi, approach
  • None of these points explain the massive loss of power and engine quitting

My conclusion here is that my technique, while perhaps questionable, did not cause the failure and that there is an issue that needs to resolved before further flight. While there is a temptation to at least do a start and full power run up and lean, I will wait for my mechanic. Last thing I want is to damage something or find myself wrapped up in the trees that surround this place.
 
While you are waiting you might read a recent thread titled "Stank Idle"
the conclusion was here

"THE FIX WAS, a 4 psi spring in the flow divider. The Bendix flow divider has either a 2 psi spring or a 4 psi spring. The spring effectively raises the boiling point of the fuel in the stainless lines to the injectors. There is also a lycoming service instruction for rough idles when hot. Instruction 1489C can be found here. https://www.lycoming.com/sites/defau... (1).pdf The spring part number is Precision P/N 2577011. For grins if anyone wants the phenolic spacer, it is Superior part # 73161. I have been battling this issue for what seems like a year. The battle has been won. I am finally comfortable with my plane."

Link to the thread here:http://https://vansairforce.com/community/showthread.php?t=184493



I think there is high probability of Dan's fuel servo inlet screen hypothesis being the main issue. It is also really quick and easy to check that. After you remove the inlet finger strainer, have a sheet of white paper and surface to lightly tap downward on the open end of the screen and you might be surprised how much fine material falls out. It might take a lot of repeat rinsing in gasoline or solvent and compressed air until you can see sunlight on the inside of the finger screen.

It takes a lot more time and TLC to check and clean the divider and injectors.

When the cowl is off for all of that, it is really easy to put in new spark plugs.


In my experience I would not even try to take off from CEC4 full rich in hot thin summer air.
Full power is always 100 deg F rich of peak EGT.
 
"THE FIX WAS, a 4 psi spring in the flow divider. The Bendix flow divider has either a 2 psi spring or a 4 psi spring. The spring effectively raises the boiling point of the fuel in the stainless lines to the injectors.

Actually, raises the pressure in the line between the fuel control and the divider, as well as in the core of the divider. It really just increases the minimum pressure needed to raise the flow divider piston. Basic principle illustrated below.

I think there is high probability of Dan's fuel servo inlet screen hypothesis being the main issue. It is also really quick and easy to check that. After you remove the inlet finger strainer, have a sheet of white paper and surface to lightly tap downward on the open end of the screen and you might be surprised how much fine material falls out. It might take a lot of repeat rinsing in gasoline or solvent and compressed air until you can see sunlight on the inside of the finger screen.

It takes a lot more time and TLC to check and clean the divider and injectors.

IF my guess is correct, you're going to find trash in the divider and the nozzle restrictors, notably the cyls reported as cold, #'s 3/4. I'd go straight to those restrictors first. You can see through them if you hold them up to the light, or just use a 10x magnifier. The nozzle passage is larger than the restrictor bore, so no real need to remove the nozzles from the cylinder head unless you want to do a bottle check. Just unscrew the little nut on the end of the stainless line, bend the line very slightly to the side, and remove the restrictor from the top of the nozzle.
 

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back home

Long day here. My mechanic showed up with a 200HP fuel servo and we changed it out in the 30-32C sun. Before pulling the servo, we did a fuel flow test at the servo inlet. No issues. Then he pulled the line downstream from the servo going up to the divider - completely dry. Looks like the servo was the main culprit. Start test was poor, 1/3 not running at all, quit passing 1100 rpm. He then pulled and checked the divider line and injector ports. All appeared clean but after blowing them out the engine ran better at first and then worked up to much better.

I misunderstood my mechanic's comments yesterday, he wasn't saying to not lean, but rather that it should make only a small difference with the Bendix system. I took off after a full throttle best power mixture set and it behaved up to about 6000' where it started to get rough again. I leveled off and leaned a little more and once I found the sweet spot, resumed my climb to 7500'. This mixture got me home,the long way - overhead climb, IFR (I follow roads). The troubling part was that I had absolutely no wiggle room in the mixture and my FF was reading the equivalent of 10.4 gph. In the same conditions I am typically 7.8. Anyways, I nursed it home, took about 25 minutes longer than direct, but steered me away for the open wilderness.

My servo is on its way to get serviced tomorrow.

DanH, where is this filter that you spoke of? Only filter I have upstream of the servo are the gascolator and the boost pump filter. My plane is still relatively low time - 145 hours and 2 years - so I wouldn't expect much to happen yet. But indeed stuff happens.

Anyways, thanks for reading this far. This is great place to expose myself in the interest of becoming a better pilot flying a safer plane.


ADDENDUM - I had a look at my logs for this 47 second adventure. I was making 86% power at the point of failure (well above the trigger for leaning of 75%), 14 seconds into my takeoff roll. At that point I had peak 2608 RPM, 26.1" MP, 12GPH and peak EGT. In the next second, I lost 485 RPM - this is what I reacted to. I was still advancing throttle to 26.4, I pulled it out to about 17" 3 seconds after incident, by that time RPM had fallen to 1087 (really! low for 17" MP). I appear to have pushed in the power again trying to save the flailing engine as the RPMs decayed below 1000. The engine did not respond and it quit outright 25 seconds after the initial incident. EGTs, led by #3 fell quickly at that 14 second mark, as did fuel flow and Pct Power. I traveled 500 ft to the failure, showed about 55KIAS and was just pulling the nose up. I stopped in 1275' with 1000' of runway left.
 
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A video can be seen here: https://youtu.be/jmiEnqNh12A

The inlet finger screen is located directly under the AN-6 / JIC-6 fuel fitting where the fuel enters the servo. The screen can be accessed/ removed from this side by loosening and threading out the AN-6 fitting- ( the clean non contaminating method). Normally the O Rings get replaced every annual inspection, however if you are careful they can almost always be re used in a field situation after a dirty load of fuel has ruined your day. The bypass spring preloads the finger screen against the fuel inlet fitting.

The finger screen can also be removed via the large hex cap on the side opposite, (not recommended as it will spill contamination as it is drawn through the servo.)

Dan will no doubt post photos or a link to some.

On a side note, I am of the opinion this should be mandatory knowledge for anybody flying any Bendix FI
engine.
Most of us however, don’t learn about the lawn mower carb until it stops working.
 
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"THE FIX WAS, a 4 psi spring in the flow divider. The Bendix flow divider has either a 2 psi spring or a 4 psi spring. The spring effectively raises the boiling point of the fuel in the stainless lines to the injectors.

As DanH mentions above, this only raises the pressure (and boiling point) of the fuel between the servo and the divider. The only way to raise the pressure in the lines between the servo and injectors is to put a smaller orifice in the injector body itself, which gives more pressure differential across the injector.

Stock IO360 injectors carry a .028" orifice, I eventually worked my way down to .022" restrictors on my airplane and this allowed me to run 91E10 fuel in hot west Texas summertime temps without issues. One critical point to keep in mind is that with smaller orifices, you must boost the pressure you are feeding to the servo, because it will take more pressure to flow takeoff power fuel through those smaller orifices - I ended up at 40-42 psi feeding the RSA-5 servo, which is right at the top of its rated pressure window.

Additionally - if you install the smaller orifices in the injectors, there is no need to install a 4# spring in the divider - the orifices solve both problems.
 

Thanks for this link.

I am actually running a Precision Airmotive Silver Hawk EX (5VA1 I think) system. The internal filter is specifically noted to not require inspection unless contamination is suspected. From the manual

The airplane’s fuel filter needs to be maintained to ensure that the servo gets clean fuel.
The fuel filter inside the servo is a last chance filter. This filter does not need to be checked
or cleaned unless it is suspected that contaminates have entered the fuel line after the
aircraft’s fuel filter.

My gascolator is the last filter upstream and I've never seen anything in it - last inspected in my annual last month. I'm not saying that there isn't contamination, there may well be. My maintenance procedures didn't miss anything in the servo as they aren't indicated for the model I have. I guess we'll see what Progressive Air has to say when they inspect the unit. I don't think there's much question that fuel starvation was the cause of the engine power loss or that the servo was the root of that starvation.
 
I operate my RV-7 with a Lyc IO-375 (Titan) on hot SoCal days mostly at S.L.
A few hours ago, I was having one heck of a time hot starting my engine. When it finally started, it would run rough on the taxi out - - sometimes requiring me to run the elec F.P. to keep it running. Never had a problem developing full take-off power. BUT on climb out leaving around 3,000 ft she starts to slightly "chug" with very minor oscillations on the MP gauge. It almost feels like the prop is out of balance. Once level at cruise it slowly goes away. After landing, there is never a problem taxiing to parking - - engine runs very smooth. This "chug" occurrence ONLY happens on the second leg of my flight - - NEVER on the first flight even when the OAT is warm. My oil temp usually runs in the 225* range with CHT's around 380*.

My mechanic sent the mags out and they were off 20* internally. We also sent out the fuel servo but that checked fine. I also had a Showplanes oil cooler mod installed which really dropped my oil temp. I haven't flown a "2 leg" flight yet to see if this cured my "chug" problem. I'm hoping it did.

Anyone have any theories on why this happens ONLY on the second leg?
 
Additionally - if you install the smaller orifices in the injectors, there is no need to install a 4# spring in the divider - the orifices solve both problems.

Actually it doesn't. The smaller restrictors will help increase the pressure at mid-RPMs and up, but it does nothing to help increase pressure at idle level fuel flow rates. Only the spider will do that.

If you could create enough restriction at the injector to up the pressure by 2 #'s at 2 GPH, it would need a lot more than 25 PSI to push 18 GPH through them. This is why you have a spider; It increases the backpressure at idle level fuel flows. These injectors don't have the range to support that type of spread.

I have 022's on my 320 and the 4# spring still made a significant difference at idle in hot ambients.

Larry
 
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Precision 2577011 4 psi Spring Source?

I am having a similar idle issue on my new IO-360-M1B. Engine runs fine at flight power and after landing, but after hot start it runs very rough.

I will double check the fuel screens and filters.

I am having difficulty finding the 4 psi spring, tried all of the usual AC supply houses. Does anyone know where I can buy this spring?

Thanks,
Frank
 
Thanks for this link.

I am actually running a Precision Airmotive Silver Hawk EX (5VA1 I think) system. The internal filter is specifically noted to not require inspection unless contamination is suspected. From the manual

Silver Hawk eh? Ahh, the joys of long distance diagnosis.

The Silver Hawk is unique in that it requires a 32 micron fine filter prior to the servo.

Put another way, that low maintenance last chance internal filter assumes small diameter filtration upstream. Your gascolator is unlikely to meet the requirement.
 
I am having a similar idle issue on my new IO-360-M1B. Engine runs fine at flight power and after landing, but after hot start it runs very rough.

I will double check the fuel screens and filters.

I am having difficulty finding the 4 psi spring, tried all of the usual AC supply houses. Does anyone know where I can buy this spring?

Thanks,
Frank

Airflow Performance. This will not help much with rough running after a good heat soak though. Best approach for that is a purge valve. After shut down, the engine area gets very hot and all the fuel in the under cowl area gets hotter than the fuels boiling point. The spring will help a bit in this scenario but won't likely eliminate it.

Larry
 
On my rocket I was experiencing some roughness at high power settings. My mechanic suggested this inlet screen and in fact it was partially plugged. As it turns out I was using TSC fuel transfer pump and the supplied hose was of dubious quality. It was replaced with a proper hose and all issues went away.
However, after following this thread I will start using a cap on the supply hose!
 
Silver Hawk eh? Ahh, the joys of long distance diagnosis.

The Silver Hawk is unique in that it requires a 32 micron fine filter prior to the servo.

Put another way, that low maintenance last chance internal filter assumes small diameter filtration upstream. Your gascolator is unlikely to meet the requirement.

Well, that's something definitely wrong with my fuel system. I had not caught this requirement, which reads
The fuel supplied to the servo shall be filtered to 32 micron nominal. This filtration may occur prior to the engine driven pump, but all other pumps
and valves shall be upstream of the filter.

My current fuel system downstream from the selector valve is:

90 micron prefilter
FlyEFII boost pump
Andair Gas325 Gascolator - 70 micron
engine driven fuel pump
Red Cube fuel flow transducer
Silver Hawk EX servo

Looks like I should try to get a 32 micron filter between the Red Cube and the Silver Hawk. (maybe between the engine driven fuel pump and the gascolator would meet the requirement) I'm very curious to hear what they find in that last chance filter.

Now identifying a suitable fuel filter might be a challange. Searching ACS didn't identify much other than a cheap plastic one with barb connectors and a 10 micron one (MICRON 10 FUEL FILTER). The 10 is a bit spendy, not terrible, it seems to support 15.3 gpm so the finer filter should be ok. Anyone have thoughts on that particular filter?

Thanks for looking that up Dan.
 
If you go with 10 micron, make sure it's big. 10 micron will capture almost everything and plug quickly.

We specify 40 for our EFI systems, both pre and post pump. 70-90 is too big for proper pump and injector protection IMO.
 
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That might fit the bill perfectly. That other 10 micron filter is really small with a note saying it need to be inspected frequently. I don't image a blocked filter would do much for sustaining fuel flow and keeping the fan at the front running.
 
Claude, back up just a bit.

First, before doing anything, see what the overhaul shop finds in your inlet filter...you know, confirm the problem before chasing a solution.

Ok, assume they find garbage. Remember, a Silver Hawk is pretty much a RSA-5 cut from billet. They use the same type of inlet filter, which is 75 micron in the RSA-5. I don't know why Precision wants 32 micron pre-filtration, but I suspect it has more to do with CYA than engineering....and it explains how they can recommend not checking/cleaning the inlet filter. One approach might be to ignore the manual's remarks and simply clean the Silver Hawk's inlet filter on a regular basis.
 
Claude, back up just a bit.

First, before doing anything, see what the overhaul shop finds in your inlet filter...you know, confirm the problem before chasing a solution.

Ok, assume they find garbage. Remember, a Silver Hawk is pretty much a RSA-5 cut from billet. They use the same type of inlet filter, which is 75 micron in the RSA-5. I don't know why Precision wants 32 micron pre-filtration, but I suspect it has more to do with CYA than engineering....and it explains how they can recommend not checking/cleaning the inlet filter. One approach might be to ignore the manual's remarks and simply clean the Silver Hawk's inlet filter on a regular basis.

Good sound advise there Dan. If that's only a 75 micron filter, it shouldn't catch anything behind my gascolator at 70. Not really all that "last chance" is it.
 
Paper/cellulose elements and water

Take care to ensure that whatever filter you use it can flow fuel with a bit of water - most paper/cellulose elements struggle with that.
 
I contacted Precision Airmotive during my build regarding filtration for their Silver Hawk EX-5VA1 servo. They indicated that a 40-50 micron filter in leu of the 32 in their installation specs would be OK.

I have a valve, Airflow Performance 125 micron filter, boost pump, 70 micron Andair gascolator, mech pump, 70 micron in servo filter arrangement.

The 70 micron filter in the servo seems kind of useless when they spec a 32 micron supply to it.

In 3 condition inspections. I have never found anything in the AP 125 micron filter or the 70 micron gascolator. I have neglected to pull the in servo filter but will do so next time I have the cowl off and every CI after. I don't expect to find anything in the servo filter though since I have never found anything in the gascolator.

I have contacted Andair to see if a 32, 40 or 50 micron filter is available for their GAS375 gascolator.

This thread has got me reevaluating my fuel system and to look at airport fuel delivery systems (especially nozzles) more carefully. Thank you.
 
Servo back from overhaul

My failed servo is back now. The only notes I got from the shop was that they completed an overhaul with a new bearing kit. They had lost the notes that came with with the servo explaining the problem and serviced it without any history, from just the examination of it. I presume this means that they found a problem with the bearing.

It's back on the plane now, just waiting on final adjustment and I'll go out and see how it works. Definitely low time (143.5 hours air time) for a failure, I was not charged for the overhaul.

I put the temporary 200hp Mooney servo through a bit of work, 19.5 hours air time. Got to know it fairly well, I had to since most of the starts were hot. It did seem to be burning more fuel, it was pickier to lean out. I think my red cube was reading a bit higher than usual too (in addition to the known extra fuel burn). I did learn that I could do absolutely nothing after the pre-start boost pump run with mixture at full rich. It was just too much fuel for any situation.

Hope to have everything return to normal with my original servo. I'll post my findings after a few flights.
 
Claude,
A little Monday morning quarter-backing going on here, and lots of technical help. You’ll have to decide what part of that help is valid, and it looks like you already have. I hope you have corrected the error and can enjoy a trouble free engine.

When I read a post like this, that requires quick decision making by the pilot, I am interested in what happened from a pilot’s perspective, in the heat of the moment. In my opinion, the bottom line is -
. Was anybody hurt?
. Did you bend any metal?
. Was there any property damage on the ground?

If the answer to these questions is no, I don’t care what procedures, checklists, etc were followed - the outcome was a complete success. You did the right thing, and you did it like a professional. Your response was immediate, even though your throttle response was 3 seconds. In human factor terms, this is very fast. The fact that you may have increased the throttle after this decision was made is most likely attributed to a rapidly decaying airspeed and substantial pitch change likely to be needed in that phase of flight. The outcome was good, so you are good. Way to go Claude. You could have become a statistic if you hadn’t responded in the way you did and I mean the mental decision to take control of the situation while you still can. That’s my takeaway from this incident, and what I hope I can do when confronted with a similar situation.
 
I'm quite pleased with my response to this incident, there is nothing that I would have changed in my reaction. The fact that wasn't completely clear at the time was that there was no flight involved here, my nose wheel was barely off the ground, my mains were still firmly planted.

If I were to write down my thought processes as this was happening it would go like this.

- Airspeed crossing 55 kt, apply back pressure to start lifting off.
- Instant engine sound change indicating significant power loss
- Immediate response is abort takeoff, first action is to reduce the back pressure that I had just applied
- second response, pull throttle back as I bring the rolling speed down
- after several seconds have passed, it is clear that by engine is struggling to stay running so I ease power back up for the sole purpose of keeping it running. Not at any time was this intended to allow a continuation of the takeoff. I just didn't want the engine to stop.
- I assessed that I had plenty of runway left so I used only a little braking to come to a stop. The actual engine quit was simultaneous with the complete stop.

At no time during this short incident did I have any concerns about the outcome, there was no panic, no concern for my own safety. I knew in that instant that I was not off the ground much if at all and that I had lots of runway. There was of course concern about the engine, hence the effort to keep it running. I don't think my pulse even went up, there was no danger response. Later there was a realization that this couldn't have happened at a better time in the takeoff roll (other than earlier) and that had this power loss occurred after I was airborne and just past the end of the runway, the local area would have left me with very few options that would have saved the plane or the pilot.

I was a little anxious to get the plane off of the runway, I rolled to the right edge to give me an easier time pushing it off if I needed to. My restart attempt wasn't done with great confidence, but I needed to try to get it off the runway. First start attempt was clearly starving for fuel, so I did a flooded start - boost pump on for a few seconds, crank with WOT and ICO until I picked up some interest in turning over, then throttle back to half and coax the start with the mixture. When the engine started and was running extremely rough, I had a choice - taxi it back to the apron or shut down and deal with the issue on the runway. I decided to try a taxi back, at this point I didn't know if this would damage anything but I considered my situation as being a significant engine issue that I wasn't going to be fixing on the runway so I taxied back.

It's been close to 2 months now, I haven't second guessed my actions at all, at least not from the point of the initial power loss. If my experience helps someone other than myself, that's a great bonus, but I'd like to think that nothing that I did was anything more than immediate instinctive reaction that any pilot would have had. In fact, if a pilot didn't respond like this, I question the wisdom of ever being in control of an airplane.
 
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