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I am having a hell of a time starting the engine in my 201.  Recently overhauled IO-360.  Normal procedure is Bob Kromer's.  Throttle closed, prop forward, mixture full rich, boot on for 6-7 seconds, then off.  Throttle open 1", mixture cut-off.  Crank and advance mixture when firing.  Doesn't work.

 

I have also tried the POH method of throttle closed, pitch fine, mixture cutoff.  Boot pump on 5-6 seconds then off.  Advance the mixture to full rich, then back to idle cut-off.  (I assume this injects the pressurized fuel into the cylinders.)  Same result.

 

The engine will usually start but only after 4-5 tries.  Once started, everything is fine.

 

The one thing that worries me is the boost pump will only get to 15 lbs maybe of pressure.  Is that low?

 

I attached a link to a movie of me starting it.

 

Does anything stand out as unusual?

 

https://www.dropbox.com/s/w86qpq61a9pkaya/IMG_1262.MOV?dl=0

 

 

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I have a J with a quadrant as well.

Three remarks :

I have the throttle at what would be 1200 RPM so about 1 in open (rather than closed.)

My fuel pressure builts up a lot more progressively than yours seems to do

Seems like your battery may be weak based on how the prop sounds when you start

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I have the same J.

First of all my boost pump pressure is 25 lbs.

My starting procedure is:

 

Mixture OFF / Idle

Prop FULL Froward

Throttle at the Position after last cut off engine ( 1300 - 1400 RPM) that is about 3/4" I guess.

Master ON

Boost pump ON ( 25 lbs pressure in split second)

Mixture FULL ( 6 seconds work for me)

Mixture CLOSED

Boost pump OFF

Crank the engine. When the engine is cold it starts immediately after 1/2 of the prop turn. When the engine is preheated it takes 3-4 turns to start.

 

Hot engine start: Assuming the throttle is in the last cut off position ( 1300-1400 RPM). Don't touch anything. Just crank the engine. It takes more turns ( probably 6-7) to start. If it didn't start I prime it for 2-3 seconds ( open mixture and boost pump) and try again. Usually works fine.

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So assuming you have enough fuel in the cylinders and not to much....wonder about impulse cupping (mag) issues. As others said something wrong with starting system almost sounds like starter is going bad??? Should crank faster.

Try boost pumping longer?

To test boost pump mix idle cut off then boost on....no fuel goes in cylinders but I bet it will go right up to 25ish...try that.

Also I didn't see fuel flow gauge but you can build the pressure up with boost on idle cut off them go mix rich and look for fuel flow. Once you see fuel flow 5 sec should do it. Return to idle cut off let boost pump run for a few sec to make sure the pressure is up 22-25ish. Boost off.

That away when it fires and you shove the mix forward it will have fuel right away.

I never did like the starting instructions, but I think u got something else wrong. I'd start with battery-starter-mags....mags make a hell of a difference!

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Doesn't act like it's primed enough. Try this.

Throttle full, boost pump on, then mixture full rich for 4-6 seconds, then ICO, then pump off. Try that.

Your starter sounds like a normal Prestolite which is a heavy but durable starter. 20 seconds of cranking on a lightweight Kelly starter and the brushes melt out of the housing.

Fuel pump sounds normal too. With the mixture at ICO it should make ~25 PSI. The mixture forward it's a little less.

If none of that fixes it then look at mags and fuel injection.

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My M20E (IO360A1A) cold start procedure is that I see most often recommended and makes sense 

 

  1. throttle and mixture full forward;
  2. boost pump on 5 seconds (plus another 2 or 3 sec if air is cold) fuel pressure should peak plus a sec or two;
  3. boost off
  4. pull throttle back to 1000-1100 position,
  5. pull mixture back to (near) cut off position;
  6. crank engine while being ready to advance mixture when engine fires. 

From my checklist:

 

MIXTURE/THROTTLE/PROP:COLDSTART:ALLFULLFORWARD

MASTER:ON

VACUUM:CHECK

CLOCK/TIMER:SET

JPI:SET

FUELBOOSTPUMP:5SEC.(COLD)

MIXTURE:CUTOFF

THROTTLE 1/4”

PROP:“CLEAR”

STARTER:ENGAGE

MIXTURE:ADVANCE

THROTTLE:1100RPM

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I would make sure the Mags are timed correctly and the plugs gaps are good.  I had a 100 hours on my IO-360 overhauled at Lycoming and ran into the same issues my timing was off and plug gaps were out of tolerance.  Re timed and re gapped and all has been well.

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The Lycoming IO360 is always flooded. I never run the boost pump before starting unless the plane has been sitting more then a week. If it doesn't get pressure after a couple of blades I turn it on while cranking just to speed things up.

If you do run the pump before starting do it with throttle and mixture at cutoff. If the mixture is advanced with the pump on it just pumps fuel into the cylinders, floods the engine and fouls the plugs.

I just cold start with the throttle open about 3/4 inch and mixture full rich. It starts as soon as it gets fuel pressure. Actually, it starts instantly then dies. Then starts for real when it gets fuel pressure. Usually in less then 5 seconds.

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U live where it's hot....(and nice this time of year) but up north it's tough to prime it to much. Seems like if it doesn't start or even fire I always wonder if it's flooded or not enough fuel....Ya, know cause is if it's flooded and prime it more = really screwed....

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I may well be completely wrong on this or not have read closely enough, but if you have the throttle off during priming, no fuel is getting to the engine.

 

I have experienced similar starting problems when I shortly realized to myself..."you idiot, you have the throttle off."

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I used to live in Denver and regularly flew in sub zero weather. I have flown to airports where there was no preheat available and successfully started the engine when it was -20 F. It never needed to be primed. It just makes it worse.

 

Fuel sprayed into a moving stream of air will vaporize better then a pool of fuel sitting on your bottom plugs!

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My procedure on my 201 is slightly different.  Throttle 1/4 - 1/2", prop full, mixture closed.  Boost pump on for 5 sec, Fuel press = 25, boost off.  mixture full rich (fuel pressure falls, of course), then crank.  After starting adjust mixture for ground ops.  Never have starting problems with this procedure.  I also have the Concorde battery

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I went through this with my J. Tried nearly everything. Try this: firewall everything, boost 3-4 seconds or until fuel pressure needle maxes out, throttle cut off and advance 1", mixture cutoff. Now here's the important part, wait about 15 seconds. Get your seatbelt on, etc. This gives the fuel time to vaporize. Now, light it and bring the mixture in when it fires. Sometimes if it doesn't fire right away I bring the mixture in early just a hair. For what it's worth, I eventually broke down and installed the electroair electronic ignition and that pretty well solved my problem. Try this first. Good luck!

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Fuel, air and sparks.

Think of most of the planes we learned to fly in, most had a hand fuel primer.

With the throttle and mixture closed and at ICO, no fuel will get to the cylinders. The fuel pressure pick up is off the servo finger screen not the flow divider, so fuel pressure indication does not mean fuel to the flow divider and nozzles.

I would suggest putting everything to the stops turn on the pump to raise the fuel pressure, turn off the pump, leave the mixture rich, retardation the throttle to idle, start the engine.

Clarence

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Hey guys, I'm new to Mooneyspace. I'm learning so much. I'd like to echo what kevinw said. In my old skyhawk (320 carb.) I would prime and then listen to the ATIS. This gave the fuel a chance to vaporize and much more likely to ignite. It really made a difference.

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