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Start up issues


Vlakvark

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Hi everyone

I pulled the plane out today for a quick flight. Was inside the hanger (temp60F). Had the mixture and power forward. Primed till FF. Back on the the mixture and power 1/8 open. Cranked the engine, advanced the mixture all in but the plane will not start. Never had this issue till after the anual. Took me 15min to get it going. Any suggestions?

JT

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My experience with K models is that if they don't start, they are not getting enough fuel

My technique is: Throttle full, Mixture full, High boost for 6 seconds, Prime for the length of time specified in the POH (3-4 seconds at 70 degrees, as much as 10 seconds when cold). Wait 15 seconds (for fuel to vaporize). Crank. If it starts and falters, prime some more.

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Don is right on, the technique you describe is for a Lycoming so I assume you formerly flew something like a Lyc IO-360. The Continentals have different procedures and need a number of seconds to prime. I use the same 6 sec that Don refers too above. A good review of your POH should be a big help.

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I'll echo Don and Paul, on the start up tech on tsio-360s.  You probably know this, but one small addition to Don's procedure; after priming and waiting, retard throttle to approx. 1/8" open then crank.

Note, sometimes a blip or three of the primer switch is needed at first start if it catches and stumbles a little.

 

William

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1 hour ago, WilliamR said:

I'll echo Don and Paul, on the start up tech on tsio-360s.  You probably know this, but one small addition to Don's procedure; after priming and waiting, retard throttle to approx. 1/8" open then crank.

Note, sometimes a blip or three of the primer switch is needed at first start if it catches and stumbles a little.

 

William

Oops, yes, absolutely. After pumping and priming, move throttle to 1/8th or so, leave mixture full rich, then crank.

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The primer switch went belly up. So they decided to run thr Hi-boost pump for the primer. I dont know if that makes a difference because I thought that both supply fuel for the start. Dont know if Im using to much boost...

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16 minutes ago, Vlakvark said:

The primer switch went belly up. So they decided to run thr Hi-boost pump for the primer. I dont know if that makes a difference because I thought that both supply fuel for the start. Dont know if Im using to much boost...

It is my understanding that the boost and primer use the same pump, but they pump fuel into different places in the intake.

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On 3/9/2017 at 11:15 PM, DonMuncy said:

My experience with K models is that if they don't start, they are not getting enough fuel

My technique is: Throttle full, Mixture full, High boost for 6 seconds, Prime for the length of time specified in the POH (3-4 seconds at 70 degrees, as much as 10 seconds when cold). Wait 15 seconds (for fuel to vaporize). Crank. If it starts and falters, prime some more.

+1.  Same technique I use.  If you leave the safety cover on the high boost you can push the top of the switch and it won't go into the detent, so it will shut off as soon as you release it.  

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Low boost and high boost run different rates of fuel flow using the same pump and two different switches.  Electrically it delivers a higher pump speed.

1) you can hear the difference between the two.

2) you can see the difference on the FF gauge.

3) the POH has instructions to use one or the other with associated time with the switch on. three mississippis or six mississippis or whatever the number of seconds is based on the OAT.

4) did you say one of your switches isn't working?

5) you would at least need to know if the pump is only working on the high setting or the low setting.

6) if you deliver too much it will be difficult to start.

7) if you deliver too little it will be difficult to start.

8) if you only get Lo boost. What will you do in the event of a mechanical fuel pump issue?

9) if you only get Hi boost.  How will you keep the engine running during the early stages of a cold start?

10) This is a long way of saying you want both switches working properly so you can get the fuel you want delivered to the engine when you need it.

Of all the airplane engines available, Continental has the easiest written start technique to follow, and the best priming system available.

Have your mechanic explain what they changed when the switch didn't work.  Which switch is the dead one? Now which one is connected.

See my confusion?

Best regards,

-a-

 

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With temps in the 60s it is a good place to start...:)

read your POH for specific instructions.  Follow exactly as they say...

Some things can be easily missed...

My IO550 POH says.

1) throttle in full

2) mixture in full

3) prime for X seconds. ( Lo boost for Y seconds, Hi boost for Z seconds )

4) throttle back to 1/8"

5) count off ten more seconds to allow for vaporization (don't rush vaporization can take more time when it is colder)

 

6) If you don't put the throttle all the way in, the amount of boost will have changed from what is being asked for.

7) If you don't reset the throttle, you are going to have some disappointed neighbors...

8) fear of leaving the throttle in gets in the way of the proper procedure.

9) have your feet on the brakes for starting.  It will happen the first time you get distracted... it takes a second or two to realize your feet not on the brakes and the plane does start moving quicker in a second or two...

10) if you try this a few times and you know that you have flooded it. Follow the flooded Start procedure also in the POH.

You do have the PoH right?

If you need one, they can be ordered through the MSC network...

See if somebody had posted a POH for your plane.

Best regards,

-a-

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V,

I looked up primer timing in my checklists this morning....  for IO550

i have one reference where there can be either Hi or Lo used.  It indicates using high for 5 seconds, or Lo for 15 seconds.  This gives a hint to a flow rate for one being 3X the other...

When temps are below 40°F the Lo is used continuously for and after start...

Check your E-procedures.  See if it references using Hi boost for a fuel pump failure.

Check your climb procedures to see if it references a fuel pump setting on/off.  The IO550 has the pump on during FT automatically.

You can probably search the Internet to find the manual that is written by the engine manufacturer for your engine.  It gives a slightly different perspective than the airframe manufacturer one.  (Interesting read)

This comes from the checklist for my IO550, your engine may be completely different.  PP thoughts only, not a CFI or mechanic...

Best regards,

-a-

 

Edited by carusoam
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Yes you read it correct. The broken part sits on top the engine with fuel lines that is a sealled unit. That unit is done. I dont know the name of the unit but I can get a picture. They by-pass that unit to use the hi-boost and now I'm heaving trouble cause a new unit is 2500 bucks without the US-CAN conversion. 

 

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On March 13, 2017 at 0:33 AM, Vlakvark said:

They removed the prime switch. I am only left with hi-boost and low-boost. Both work but Im having trouble get the right amount fuel to engine. 

Most Continental engine don't have the priming solenoid valve, it seems to be a TSIO360 thing.  Most are primed with the throttle wide open, mixture full rich then boost pump on high until there is good flow indication.

Clarence

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Ok. I am confused. Went out to go fly. Tried the Hi-boostpump. No joy starting the plane. I though....mmm. Let's try the primer switch( I was under the impression that the switch will not work due to the fuel solenoid been removed). Pushed the primer and wholla. She, primed and no issues. Here is a picture of what the mechanic removed. Did I missed something??

IMG_2286.JPG

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There needs to be a clear understandable statement of what the mechanic did and why...

Having parts of my fuel system removed and not replaced would make me unable to fly.

A solenoid valve has two parts that can fail, the electronic part and the valve part.  It is often the electronic part that gets swapped out in about 10 minutes. 

What was put in the valve's place?

---------------------

I am probably mis understanding something....

Realistically this doesn't sound right.  

Mechanics can't decide to swap or leave out parts on a certified aircraft like a Mooney.  They are supposed to remove and replace using the same or equivalent parts...using proper procedures and documenting the change in the log book.  When this can't be done, it becomes an air worthiness challenge.  The plane won't conform to its original design with the wrong parts or without the right parts.

If your plane is supposed to have a hi and low boost it is because both are needed functions.  It sounds like you might be missing one function.

See if you can find out what really was done on the plane.  Talk with the mechanic, read the log entry.

you know?

PP thoughts, not a mechanic...

Best regards,

-a-

Edited by carusoam
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You need someone more knowledgeable than me to properly explain it, but my understanding is that the electric boost pump is used to furnish fuel during the starting process, and feeds both the "primer" and the "boost function". The pump pushes the fuel to the diverter valve. Electric power is furnished to the diverter valve and when activated, it "directs" the fuel to one spot in the induction system. When not activated, it goes to a different area. (I don't know which is which, nor where exactly these two areas are.) So in theory, if the diverter valve was removed, it would have to be plumbed to push fuel to one or the other "places". I presume it would be directed to the area ordinarily serviced by the boost function. (since the primer is only used to aid in starting). I further assume that if this was plumbed correctly, it would have no effect on the functioning of the engine during flight. And I think the Continental engines start pretty well during hot, cold and normal times, so the lack of priming would not be a terribly bad situation.

This priming system is not used on most planes using this engine, and in the K manual, it notes:  The priming system is optional on the E, F, KB and LTSIO-360-E. Standard equipment on the TSIO-360F model engine.  

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