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Starting my M20F


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Just a quick verification...does anyone start the O360 like this?

-    Advance throttle 1/4 total travel 
-    Turn the fuel pump on
-    Advance the mixture and watch for a good rise on FF
-    Pull mixture back to cut off
-    Fuel pump off
-    Engage starter 
-    When engine fires steadily advance mixture
 

It's a bit different from my POH (mainly the fuel pump operations...) but the engine starts much better...

Thanks!

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Just about exactly what I do for a normal start; I do open the throttle all the way and mixture all the way and hold the fuel pump for about 5-6 seconds. Return throttle to 1/2 inch open and mixture to ICO. Crank and advance mixture, when it fires smoothly, quickly advance mixture until it runs smoothly. I think it is a bout the same. BTW, don't you have an IO360A1A in your F rather than an O360??

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2 minutes ago, Stephen said:

Just about exactly what I do for a normal start; I do open the throttle all the way and mixture all the way and hold the fuel pump for about 5-6 seconds. Return throttle to 1/2 inch open and mixture to ICO. Crank and advance mixture, when it fires smoothly, quickly advance mixture until it runs smoothly. I think it is a bout the same. BTW, don't you have an IO360A1A in your F rather than an O360??

Yes, I have a IO360A1A...I was sparing some typing!

Do you turn the fuel pump back on for the runup and TO?

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Just a quick verification...does anyone start the O360 like this?
-    Advance throttle 1/4 total travel 
-    Turn the fuel pump on
-    Advance the mixture and watch for a good rise on FF
-    Pull mixture back to cut off
-    Fuel pump off
-    Engage starter 
-    When engine fires steadily advance mixture
 
It's a bit different from my POH (mainly the fuel pump operations...) but the engine starts much better...
Thanks!


I don’t recall what the POH says, the procedure I use is to do everything you do but I start with the mixture full forward. Boost on until pressure reaches peak, idle cutoff and then start.


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There is often confusion when saving typing.... or printing (OMs and POHs)

...1/4...

1/4 of Throttle travel, or 1/4” of throttle travel...

The 60s owner’s manuals left a lot flexibility like this on purpose?

 

There is a purpose for every step in the procedure. Even if you made up the procedure yourself... you might share why you did each step, what it does... the logic you use...

 

starting procedure is very temperature dependent.  Fuel evaporation rates make this happen.

 

it is helpful to include the OAT and the engine temp in your statements...

As for the mixture being pulled all the way out for starting?  Makes sense for a hot start... because a few bubbles in the fuel system can push a lot of liquid fuel towards the engine...

For a regular start, not so sensible...? Extra steps, limits the needed fuel delivery...

its all about getting the right amount of fuel to the engine...  

There are a few different ways of getting the right amount... so pick what works for you...

The worst that can happen, you flood the engine and then follow the flooded engine start procedure...

Summer temps, easy to start...

temps below 40°F, things start to get finicky...

below 20°F, things get terrible... think pre-heat...

if the engine doesn’t start within a half dozen blades going by... this a sign of opportunity...  room for improvement in the procedure... or something mechanical is wearing... SOS, or mag timing, or...

So... what was the advantage of beginning the regular cold starting procedure with the mixture all the way out?

PP thoughts only, not a mechanic...

Best regards,

-a-

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COLD, I do the procedure from your original post except I leave the mixture rich or close to full rich after priming (fuel pump on, 5”, off), then engage starter.  After she fires I adjust for 1000rpm and lean as far as possible until it almost quits.

Now HOT, is a totally different approach.  Don’t touch anything from shutdown... throttle ~1/4, mixture cutoff, NO prime (no fuel pump).  Crank.  Be prepared to add mixture when she fires.  Will take 10-15 blades if normal start is 5.  There are 100 other feasible ways to hot start.

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2 hours ago, FastTex said:

Just a quick verification...does anyone start the O360 like this?

-    Advance throttle 1/4 total travel 
-    Turn the fuel pump on
-    Advance the mixture and watch for a good rise on FF
-    Pull mixture back to cut off
-    Fuel pump off
-    Engage starter 
-    When engine fires steadily advance mixture
 

It's a bit different from my POH (mainly the fuel pump operations...) but the engine starts much better...

Thanks!

It doesn't matter whether you turn on the pump or advance the mixture first, nor does it matter whether you then turn the pump off or pull the mixture to cutoff first.  As long as both the pump is on AND mixture full rich for about 5 seconds, you're good.

I used to think that maybe pulling the mixture to cutoff before turning off the pump was better because it leaves more pressure in the fuel system during cranking, but I tried both ways and it seemed to make no difference at all.

And FWIW, I no longer advance the mixture to full rich after the engine catches, I just advance it half way or so.  It seems to start fine that way, and no sense dumping more fuel than necessary out the exhaust.

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11 hours ago, FastTex said:

Just a quick verification...does anyone start the O360 like this?

-    Advance throttle 1/4 total travel  -   I was told 1" of throttle lever open
-    Turn the fuel pump on - Start counting to 6 seconds
-    Advance the mixture and watch for a good rise on FF
-    Pull mixture back to cut off - After reaching 6 second count
-    Fuel pump off
-    Engage starter
-    When engine fires steadily advance mixture - to about 1/3 in summer, 1/2 in winter.   Adjust down to minimum idle
Doing the two handed dance bring the RPMs to between 1100-1200   When sitting always be between 1100 and 1200-  reduce for taxi to save the brakes.

It's a bit different from my POH (mainly the fuel pump operations...) but the engine starts much better...

Thanks!

Hot start.

Shut down at 1100 RMP with mixture

Get back in and Crank

Slowly add mixture to above settings

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15 hours ago, carusoam said:

There is often confusion when saving typing.... or printing (OMs and POHs)

...1/4...

1/4 of Throttle travel, or 1/4” of throttle travel...

The 60s owner’s manuals left a lot flexibility like this on purpose?

 

There is a purpose for every step in the procedure. Even if you made up the procedure yourself... you might share why you did each step, what it does... the logic you use...

 

starting procedure is very temperature dependent.  Fuel evaporation rates make this happen.

 

it is helpful to include the OAT and the engine temp in your statements...

As for the mixture being pulled all the way out for starting?  Makes sense for a hot start... because a few bubbles in the fuel system can push a lot of liquid fuel towards the engine...

For a regular start, not so sensible...? Extra steps, limits the needed fuel delivery...

its all about getting the right amount of fuel to the engine...  

There are a few different ways of getting the right amount... so pick what works for you...

The worst that can happen, you flood the engine and then follow the flooded engine start procedure...

Summer temps, easy to start...

temps below 40°F, things start to get finicky...

below 20°F, things get terrible... think pre-heat...

if the engine doesn’t start within a half dozen blades going by... this a sign of opportunity...  room for improvement in the procedure... or something mechanical is wearing... SOS, or mag timing, or...

So... what was the advantage of beginning the regular cold starting procedure with the mixture all the way out?

PP thoughts only, not a mechanic...

Best regards,

-a-

Always love your analysis @carusoam , very helpful to summarize and organize 

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Mine fires on first or second blade if do this:

mixture full rich, throttle open halfway, boost pump on for 5 seconds, pump off, mixture cut off, throttle pulled.   Wait 5-10 seconds, sometimes wait longer in winter time.   Crack throttle 1/8”- 1/4”, crank and push mixture rich at the same time.   

I find that the key to immediate start is waiting for fuel to vaporize/atomize after priming.  Especially in winter.  

I’ve started it different ways in the past, but this way seems to work best for me. ;)

I used to start cranking right after the boost turned on for 3-5 seconds, but I usually saw a few more blades before firing.  Letting the fuel sit in the cylinders for a few moments seems to help.  

Edited by Browncbr1
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There are a lot of complicated procedures out there.  Mine are very simple.  I run the engine to 1000 - 1200 RPM and shut down with mix.  

Cold start: don't touch throttle, mix full rich, fuel pump on (3-5 seconds summer, 5-7 seconds winter), crank, fires on 1st or 2nd blade.  

Hot start:  don't touch anything, crank, fires on 5-6 blades, slowly advance mix

I will say it was a lot different before the A&P properly adjusted my idle mixture.

Edited by skydvrboy
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