Is an airplane that's never pre-heated safe to fly?

MachFly

MachFly

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MachFly
I flew a rental Archer (Lycoming IO-360) with a buddy of mine a few weeks ago and now planning on going up with him again in the next few days. Today I found out that most people (including owners) who fly that plane never pre-heat it, regardless of the temperature, the airplane is not hangered. So I am trying to decide if the airplane is safe to fly, what do you guys think?

If I pre-heat it on my flight will it make the flight any safer considering that no one else ever pre-heats it?


Thanks

P.S. The local temperatures have been around -5C the past few days (and will be for the next week or so).
 
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If they get it started with out pre-heat there is no problem, the cold wear period is accelerated but as long as it is making the proper numbers it is OK to fly
 
Tom-D said:
If they get it started with out pre-heat there is no problem, the cold wear period is accelerated but as long as it is making the proper numbers it is OK to fly
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The airplane flies so I assume they get it started, probably not on the first attempt thought.


BTW I forgot to mention in the OP that recently the temps have been around -5C.
 
MachFly said:
The airplane flies so I assume they get it started, probably not on the first attempt thought.


BTW I forgot to mention in the OP that recently the temps have been around -5C.
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I'll bet at -5 you can't get it started with out pre-heat.
 
If it starts it will fly,tough on the engine. You also run the risk of frosting the plugs,which means you won't get it started without pre heating. Why would one not pre heat ?
 
If it's a rental from an FBO wouldn't it be in their best interest to have a line guy run out there to pre-heat it?
 
Some rental ops require preheat and either work with the FBO to provide preheat or have their own preheater. In either case, no additional cost to the renter pilot. The owners of the airplane are smart enough to know that proper preheats mean lower maintenance costs overall.

MOST rental places, however, charge for the preheats. And in those cases, a renter pilot has no incentive to pay for the preheat - it's not HIS money or asset that's being saved.
 
Just to make sure that I understood you guys right. I shouldn't be worried about losing an engine at 200ft just because the last 10 guys were too cheap to to pre-heat?
 
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And no, you don't really have to worry about catastrophic engine failure. You might need an overhaul sooner.
 
Okay thanks.
I don't want to refuse flying with someone claiming their plane is not safe based on false information.
 
MachFly said:
Okay thanks.
I don't want to refuse flying with someone claiming their plane is not safe based on false information.
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There is a way far off chance that it may spin a bearing and throw a rod if this is consistently done, but nothing I'd be particularly concerned about on takeoff, it would happen on descent.
 
Henning said:
There is a way far off chance that it may spin a bearing and throw a rod if this is consistently done, but nothing I'd be particularly concerned about on takeoff, it would happen on descent.
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Why descent?
 
MachFly said:
Why descent?
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Rod failures are most likely to happen in deceleration phases where the the engine is being driven by by external energy, ie prop driving the engine. Rods rarely fail under load. VERY minor odds regardless.
 
Henning said:
Rod failures are most likely to happen in deceleration phases where the the engine is being driven by by external energy, ie prop driving the engine. Rods rarely fail under load. VERY minor odds regardless.
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Got it
 
I've flown an Archer without pre-heat in similar weather. Yes, it will start.... with difficulty unless you primer the snot out of it and set the throttle just right. Nothing in the POH that I could find says you can't, nor could I find anything saying you need to warm it up before takeoff for whatever that's worth.

I advise a really good run-up, then on the runway power to 2000rpm with the brakes on momentarily before going to full power. I had an engine die on me once applying power too quickly.
 
cowman said:
I've flown an Archer without pre-heat in similar weather. Yes, it will start.... with difficulty unless you primer the snot out of it and set the throttle just right. Nothing in the POH that I could find says you can't, nor could I find anything saying you need to warm it up before takeoff for whatever that's worth.

I advise a really good run-up, then on the runway power to 2000rpm with the brakes on momentarily before going to full power. I had an engine die on me once applying power too quickly.
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I plan on pre-heating it, but just out of curiosity, how many times do you prime it to start in such conditions (without flooding it)?
 
MachFly said:
I plan on pre-heating it, but just out of curiosity, how many times do you prime it to start in such conditions (without flooding it)?
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If it has 4 primer tubes, I'd give it 2 squirts then let it sit for a minute, then give it 2-3 more squirts while cranking it with the throttle open and mags cold and let it sit for another minute. Set the throttle about 3/4" open, mags hot, start squirting and hit the starter.
 
Henning said:
If it has 4 primer tubes, I'd give it 2 squirts then let it sit for a minute, then give it 2-3 more squirts while cranking it with the throttle open and mags cold and let it sit for another minute. Set the throttle about 3/4" open, mags hot, start squirting and hit the starter.
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How do you crank it with the cold mags? It's got that key thing with the left/right/both/starter options. So I can't really crank it with cold mags (unless I physically disconnect them).
 
MachFly said:
How do you crank it with the cold mags? It's got that key thing with the left/right/both/starter options. So I can't really crank it with cold mags (unless I physically disconnect them).
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Bummer, I hate those switches. You'll just have to do the same thing with hot mags, it most likely won't catch anyway, but if it does, it's a good thing. even a chuff or two will give some heat to the head.
 
Henning said:
Bummer, I hate those switches. You'll just have to do the same thing with hot mags, it most likely won't catch anyway, but if it does, it's a good thing. even a chuff or two will give some heat to the head.
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I see.
Learn something new every day.
 
Someone may come along with a better procedure, all I can say is this worked for me. In cold weather- master on, fuel pump on, mixture full rich, 6-8 pumps of primer, throttle 1/4, attempt to start. If no start within about 5 seconds of cranking stop, prime 2-3 more pumps and try again.

When it starts it may run rough initially. If conditions are not terribly dirty/dusty I put carb heat on to help it warm up faster.

This has been my experience with my Archer. It loves it's primer and if it doesn't fire in the first couple of seconds, it won't in the next few... don't run the battery down trying.

Also when I did this the aircraft was not equipped with a pre-heater, it is now and I use it.
 
If it's super cold and heat simply isn't an option give it three or four primer squirts and try to start immediately. If that doesn't work then another two squirts and start cranking while cranking continue to prime. You may have to keep priming for the first ten seconds or so after it starts to keep it running. This requires about three hands.

In an Archer -- if the prop will spin you will get it started with the above sequence.

It will decrease the engines lifespan if done often but isn't going to make it more likely that you will have a catastrophic failure.
 
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You guys seem to know the start sequence for one of my snowblowers! Who told you?! ;)
 
cowman said:
Someone may come along with a better procedure, all I can say is this worked for me. In cold weather- master on, fuel pump on, mixture full rich, 6-8 pumps of primer, throttle 1/4, attempt to start. If no start within about 5 seconds of cranking stop, prime 2-3 more pumps and try again.

When it starts it may run rough initially. If conditions are not terribly dirty/dusty I put carb heat on to help it warm up faster.

This has been my experience with my Archer. It loves it's primer and if it doesn't fire in the first couple of seconds, it won't in the next few... don't run the battery down trying.

Also when I did this the aircraft was not equipped with a pre-heater, it is now and I use it.
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jesse said:
If it's super cold and heat simply isn't an option give it three or four primer squirts and try to start immediately. If that doesn't work then another two squirts and start cranking while cranking continue to prime. You may have to keep priming for the first ten seconds or so after it starts to keep it running. This requires about three hands.

In an Archer -- if the prop will spin you will get it started with the above sequence.

It will decrease the engines lifespan if done often but isn't going to make it more likely that you will have a catastrophic failure.
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Good to know.
Hopefully I won't need to use that method.
 
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