IO 550 boost pump usage

[SixPapaCharlie]

I am getting a bit of conflicting advice on when to turn it off after landing. One source is telling me to shut it down as you exit the runway and pull up flaps so like after landing check list. The other source is telling me that it needs to be the very last thing I do before pulling the mixture to shut the engine down to prevent vapor lock.

How do you do it and why? I am too new with this engine to know which source to trust.

 

[Henning]

No need to taxi with a boost pump unless you are getting a vapor lock issue.

 

[Checkout_my_Six]

I am getting a bit of conflicting advice on when to turn it off after landing. One source is telling me to shut it down as you exit the runway and pull up flaps so like after landing check list. The other source is telling me that it needs to be the very last thing I do before pulling the mixture to shut the engine down to prevent vapor lock.

How do you do it and why? I am too new with this engine to know which source to trust.

the CMI engine has the boost pump to "prevent" vapor lock. If there is no risk of vapor lock....or engine pump failure, there is no need to run the pump.

I run my boost pump (on the low setting) after a hot start....to prevent vapor lock. All other times it's in the off position....even while in the pattern and on takeoff.

 

[Ted]

There's no risk in turning the boost pump off after you land. If the engine starts to run bad, turn it back on.

I turn the pump on low as part of my pre takeoff checklist. In the 310 that's recommended. Additionally it gains me about an extra 1 gph at climb power, which helps cooling during the climb. I turn it off when my CHTs are below 380F.

What does the airplane checklist say? Follow that. On some Twin Cessnas you're supposed to run the pumps on low all the time.

 

[SixPapaCharlie]

Checklist says turn it off.
CISP says leave it on.

 

[FastEddieB]

Checklist says turn it off.
CISP says leave it on.

While with the CSIP, I guess you have to do what he or she says. Or get another CSIP.

But the "S" in CSIP stands for "Standardized". As such, in general they should each be teaching the same thing, which is "by the book".

Again, have you joined COPA? You would get a lively debate going over there.

edited to add: I just checked the POH on my 2003. Fuel pump - OFF is actually on two checklists, both the After Landing and Shutdown. As an aside, if you miss it entirely the engine will probably keep running even with the mixture at idle cutoff.

 

[SixPapaCharlie]

While with the CSIP, I guess you have to do what he or she says. Or get another CSIP.

But the "S" in CSIP stands for "Standardized". As such, in general they should each be teaching the same thing, which is "by the book".

Again, have you joined COPA? You would get a lively debate going over there.

I will join soon.

 

[narchee]

I wouldn't ask that question here. You're going to get people piping up with answers even if they've never owned a SR22 or even that engine. Always best to get the answer from people who actually know

 

[Checkout_my_Six]

I wouldn't ask that question here. You're going to get people piping up with answers even if they've never owned a SR22 or even that engine. Always best to get the answer from people who actually know

yeah....yeah.....

 

[flyingron]

On my installation the boost pump never comes on prophylactically. You only engage it when you think you've got a fuel flow problem. I use it prime it briefly on a cold start, run it longer to cool the fuel on a hot start. Otherwise the only time I use it is occasionally switching to my tips needs a little run of the pump to purge the vapor but it's better to do this on the ground before flight (easier on my nerves than having the engine quit).

That being said a real hot engine sometimes doesn't idle well on landing once slowed down. A little shot of pump helps that.

 

[NoHeat]

As an aside, if you miss it entirely the engine will probably keep running even with the mixture at idle cutoff.

Yes.

Turning the engine off is pretty much not going to happen when the boost pump is on.

I'm not sure why you would really need to turn it off earlier, unless plug fouling is a concern due to a rich mixture when taxiing.

 

[schmookeeg]

I wouldn't ask that question here. You're going to get people piping up with answers even if they've never owned a SR22 or even that engine. Always best to get the answer from people who actually know

The quoted procedures in here seem not to apply to my IO-550B, so maybe some specificity is in order.

I only run the boost pump in my B for starting and then never run the thing again. From what I'm reading, that's now how the 550 in a Cirrus (550N?) operates.

Today I learned.

 

[Tarheelpilot]

Follow the procedure in the aircraft manual. I have flown the 550 one three different airframes and in all three the pump was for start priming, vapor lock issues as necessary and emergency procedures. I can't every remember having the pump running other than for priming before start. Have only flown a cirrus once and it didn't have a 550 so there may be something unique about that installation.

 

[SixPapaCharlie]

My boost pump has "prime" and "boost" so 2 settings.
For starting we run in prime for 10-60 seconds

Then for critical phases of flight, we set it on boost which is what I have usually done on low wing planes. However, I have always turned the pump off once said critical phase was complete.

The POH says this too but the CISP disagrees. He disagrees with a lot of things though so I am trying to filter personal preference from real recommended procedures.

 

[Clark1961]

The POH says this too but the CISP disagrees. He disagrees with a lot of things though so I am trying to filter personal preference from real recommended procedures.

Maybe sit down with the CSIP and the POH to discuss the fuel system. Draw the fuel system so that it is clear how the system operates and what the boost pump is doing. The thing here is that vapor locking after landing is unlikely in the extreme. The engine has been operating at low power with good cooling airflow therefore it's about as cool as it's going to get. The fuel has been at altitude so it will be cool. About the only time vapor locking will be an issue is hot starts and rapid climbs with hot fuel.

I had to do this with my CFII and DPE after some pointed criticism they both made which turned out to be a misunderstanding/misrepresentation on their part. Maybe the book/POH is wrong, maybe it's right but following the book is a good idea until a full examination of the situation is made.

 

[hook_dupin]

The other source is telling me that it needs to be the very last thing I do before pulling the mixture to shut the engine down to prevent vapor lock.

Vapor lock on a hot start seems to be more pernicious on the SR-22 than other IO-550 aircraft I've flown. I could see keeping the boost pump on as a technique to make starts easier if you're quickly cycling the airplane.

Does your CSIP give constant SR-22 instruction or does he work for an air taxi company that does numerous restarts?

 

[FastEddieB]

I'm not sure why you would really need to turn it off earlier, unless plug fouling is a concern due to a rich mixture when taxiing.

Even that can be countered by aggressive leaning on the ground.

Many Cirrus pilots have determined which letter in M-I-X-T-U-R-E the mixture control can be pulled back to for satifactorily lean ground running, either with or without the boost pump on.

 

[FastEddieB]

The POH says this too but the CISP disagrees. He disagrees with a lot of things though so I am trying to filter personal preference from real recommended procedures.

Again, sounds like he may have missed the whole concept behind having a "Standardized" training program.

One reason the airlines are so safe is standardized training and procedures. That was what Cirrus was attempting to do when it instituted it's training to combat what was at the time an unacceptably high accident rate. I think it was, for the most part, a well intentioned and well conceived plan.

Just my take, but you should not constantly be forced to operate outside the POH to please a particular CSIP.

 

[Henning]

Vapor lock on a hot start seems to be more pernicious on the SR-22 than other IO-550 aircraft I've flown. I could see keeping the boost pump on as a technique to make starts easier if you're quickly cycling the airplane.

Does your CSIP give constant SR-22 instruction or does he work for an air taxi company that does numerous restarts?

Except that it wouldn't be effective. When the engine shuts down and the latent heat soaks the fuel system under the hood, that is when it boils all the fuel out. Put the pump on high with the mixture and throttle open, wait for the fuel flow to show full flow, count to 3 and shut it off, mixture back to idle and the throttle cracked and it will be cleared, primed, and starts within 2-3 blades.

 

[weilke]

Not understanding the different setups with fuel pumps in conti engines has killed a number of people over the years. Read your POH, understand how things work. Dont listen to anonymous people on the internet :wink2: .

 

[flyingron]

Except that it wouldn't be effective. When the engine shuts down and the latent heat soaks the fuel system under the hood, that is when it boils all the fuel out. Put the pump on high with the mixture and throttle open, wait for the fuel flow to show full flow, count to 3 and shut it off, mixture back to idle and the throttle cracked and it will be cleared, primed, and starts within 2-3 blades.

Henning's procedure is exactly what I use on hot starts. The worst starting condition is about the time it takes to shutdown, fuel the aircraft, go inside and pay and use the bathroom, and get back in the plane (30 minutes or so). Gives time for the fuel to cook in the lines. I've seen other Navion pilots open the cowling doors to try to alleviate that but I'm not sure it does anything.

 

[Henning]

Henning's procedure is exactly what I use on hot starts. The worst starting condition is about the time it takes to shutdown, fuel the aircraft, go inside and pay and use the bathroom, and get back in the plane (30 minutes or so). Gives time for the fuel to cook in the lines. I've seen other Navion pilots open the cowling doors to try to alleviate that but I'm not sure it does anything.

It'll do something, whether it's enough... Just flushing fresh fuel for three seconds is what I use hot or cold down to 50°, then I add a little more fuel as it gets colder. Makes every Continental FI engine fire right off.

 

[FastEddieB]

Makes every Continental FI engine fire right off.

Can we assume that means you've tried it on every Continental FI engine?

 

[Checkout_my_Six]

Can we assume that means you've tried it on every Continental FI engine?

I can, with confidence, tell ya.....it wouldn't work for mine.


he'd have it flooded in a NY minute.....

 

[Clark1961]

he'd have it flooded in a NY minute.....

That's where I'm at with a TSIO-360. When the engine is hot, I'll run the pump in low for a minute with the throttle open and mixture closed, then shut off the pump, crank the starter and slowly open the mixture until it starts. Takes a little cranking but it works every time. Ya also kinda need three hands to crank the starter, open the mixture and close the throttle.

 

[Checkout_my_Six]

That's where I'm at with a TSIO-360. When the engine is hot, I'll run the pump in low for a minute with the throttle open and mixture closed, then shut off the pump, crank the starter and slowly open the mixture until it starts. Takes a little cranking but it works every time. Ya also kinda need three hands to crank the starter, open the mixture and close the throttle.

that works with most CMI FI engines....but mine is a little different in that the fuel doesn't all "return".....and it will flood.

 

[Henning]

Can we assume that means you've tried it on every Continental FI engine?

IO-240, IO-360, IO-470, IO-520, IO-550 as well as the TSIO versions of the 360 & 520. That pretty much covers most of the FI Continentals, I can't think of a reasons those not on the list would act differently since they have the same FI system. Always works well. Lycomings are a PITA hot, but Continentals are easy.

 

[Checkout_my_Six]

not for all TSIO versions.....that won't work for mine.

 

[FastEddieB]

On reflection, I think that maybe this problem is endemic to ALL FI systems.

For instance, our Jeep, our Element and our Flex are all fuel injected and each requires its own particular technique for a successful start without flooding, especially when hot.

Oh, wait...

...they don't! You just turn the key and they start.

There's another thread about what's happening to GA. This thread may be part of the problem.

We may pride ourselves in mastering the technique for starting our engines, but in 2015 the vast majority of folks out there are used to things just starting. To paraphrase Steve Jobs, "It should just start!"

I'll bet this level of technique and mastery just to get an engine to start and run is off-putting to many. Its really quite inexcusable.

Oh, well, so it goes...

 

[N801BH]

On reflection, I think that maybe this problem is endemic to ALL FI systems.

For instance, our Jeep, our Element and our Flex are all fuel injected and each requires its own particular technique for a successful start without flooding, especially when hot.

Oh, wait...

...they don't! You just turn the key and they start.

There's another thread about what's happening to GA. This thread may be part of the problem.

We may pride ourselves in mastering the technique for starting our engines, but in 2015 the vast majority of folks out there are used to things just starting. To paraphrase Steve Jobs, "It should just start!"

I'll bet this level of technique and mastery just to get an engine to start and run is off-putting to many. Its really quite inexcusable.

Oh, well, so it goes...

Well played sir.....

 

[SixPapaCharlie]

I do find it odd that a 10 year old $10k car will start by turning the key but a brand new whatever price plane requires a bit of luck, the right finesse, a prayer, specific weather, etc and then that still may not do it.

 

[Bill]

I do find it odd that a 10 year old $10k car will start by turning the key but a brand new whatever price plane requires a bit of luck, the right finesse, a prayer, specific weather, etc and then that still may not do it.

Don't forget sacrificing the chicken.......definitely need the chicken. At least that works hot starting the Mooney on really hot days.

 

[FastEddieB]

I do find it odd that a 10 year old $10k car will start by turning the key but a brand new whatever price plane requires a bit of luck, the right finesse, a prayer, specific weather, etc and then that still may not do it.

To be fair, my SR22 started pretty easily.

But to be even more fair, I often had to "jockey" the power lever back and forth a bit to keep it running.

One hint: on hot days open the oil door as soon as you deplane. It lets the under-cowl heat escape much faster and makes hot starts less problematical.

 

[jesse]

I am getting a bit of conflicting advice on when to turn it off after landing. One source is telling me to shut it down as you exit the runway and pull up flaps so like after landing check list. The other source is telling me that it needs to be the very last thing I do before pulling the mixture to shut the engine down to prevent vapor lock.

How do you do it and why? I am too new with this engine to know which source to trust.

The TSIO-550 I sometimes fly has a bad habit of the engine quitting when you taxi after you land. If you leave the low boost pump on it doesn't help the problem at all. However if you bump the low boost pump on the split second it starts to quit then leave it on for a few seconds you'll stay running.

It's least likely to happen on it if you land and taxi with the mixture full rich and avoid letting the RPM get too low.

Personally I'd leave the low boost pump off unless you have problems with the engine quitting at which point I'd experiment with turning it on.

 

[Clark1961]

Don't forget sacrificing the chicken.......definitely need the chicken. At least that works hot starting the Mooney on really hot days.

I thought they only sacrificed the chicken to start those big radials...and they did that 'cause the flight engineer wuz gonna be hungry after finally getting the thing to start...

 

[N801BH]

I thought they only sacrificed the chicken to start those big radials...and they did that 'cause the flight engineer wuz gonna be hungry after finally getting the thing to start...

With the 3350's and 4360's you needed sheep... Chickens didn't provide enough food for the FE and the ground fire crew........

Ben ( had to throw in the sheep thing) Haas...

 

[Henning]

On reflection, I think that maybe this problem is endemic to ALL FI systems.

For instance, our Jeep, our Element and our Flex are all fuel injected and each requires its own particular technique for a successful start without flooding, especially when hot.

Oh, wait...

...they don't! You just turn the key and they start.

There's another thread about what's happening to GA. This thread may be part of the problem.

We may pride ourselves in mastering the technique for starting our engines, but in 2015 the vast majority of folks out there are used to things just starting. To paraphrase Steve Jobs, "It should just start!"

I'll bet this level of technique and mastery just to get an engine to start and run is off-putting to many. Its really quite inexcusable.

Oh, well, so it goes...

Well, in your car, you have injector nozzles that turn on and off to regulate fuel flow, and a high pressure pump to supply the fuel that runs full time. The moment you turn the key on, the system self bleeds. In our antiquated mechanical FI systems, you have to do that yourself, but since the nozzles are full time flow, you can spray too much fuel.

If you have a Continental, you can spend $60k and replace it with a FADEC engine and get all those feature you are used to with your car.

 

[narchee]

The most stressful time for me when flying is starting the damn thing. Usually the more people you have watching the harder it is to start. And why is it that if you try to start and fail that everyone on the ramp who was NOT looking at you now LOOKS at you. And you can see it in their faces what they're thinking "Oh look that shmuck didn't prime properly" or "What a doofus he flooded it!"

 

[Bill]

"Oh look that shmuck didn't prime properly" or "What a doofus he flooded it!"

Even better if you're taking up a new pax. "Damn, guy can't even start the engine, I'm not flying with him"

 

[SixPapaCharlie]

Even better if you're taking up a new pax. "Damn, guy can't even start the engine, I'm not flying with him"

Oh I hate that feeling.
I feel like they are going "Um, I didn't realize this was a junker"