Cold starts.

[Scottishflyer182]

Hi , I own a new cessna 182. Wanted to go flying today.

Clear skies, but very cold. If fact so cold my lovely plane did'nt want to start. I eventually flattened the batt.

Is this normal>? surely not.

What am I not doing or doing incorrectly??

Cheers

[llanfairpg]

Most likely under use of the primer--have a look at the POH

[M609]

Define "very cold"

Getting a Cessna to start without a engine heater can be a bit of a b****.

...but I gather my very cold is a bit colder than your very cold. :O

Be careful not no get too carried away with the primer though, I've seen a couple of carb fires on cold start due to that.

[fireflybob]

Read and follow the advice given in the aircraft Pilots Operating Handbook and/or Flight Manual. Some of the so called checklists that are on the market are pretty hopeless when it comes to starting the engine in different circumstances.

[172driver]

What is 'very cold' ? I have found that a C182 (old one with 12v system) starts easily in just above zero deg weather if you pull the prop through a couple of times before starting. However, beware! and see this thread (http://www.pprune.org/forums/showthread.php?t=298991) for caveats !

In my particular case, no primer at all needed, just a few quick squirts with the throttle while engaging the starter. That said, all engines are set a bit differently, so you may have to experiment a bit.

[Scottishflyer182]

I should have said that its fuel injected ( no caberators). Followed the POH but no luck.

Its now at the engineers so I will let you know what he says and hopefully what the problem was or is.

Cheers

[stiknruda]

SF182 - what engine/injector do you have?
The aircraft type is prety irrelevant!

[IFMU]

As a new pilot I caught a C172 on fire once. Scared the *rap out of me. It was hard starting, I made the critical error of getting too much fuel in the induction system. Did this by pumping the throttle in my failed gyrations while cranking. I put it out right quick with the fire extinquisher, no damage done. Had the A&P come out and look it over.

Since this event I've had a keen interest on the right thing to do, as I had already figured out the wrong thing. One bit of advice I have been given, which seems to work for me, is to prime the engine before you start the preflight walkaround. Fuel puddled anywhere won't burn. Fuel in vapor will. When it is cold give the fuel more time to become vapor before you crank the engine. This seems to work for me.

-- IFMU

[Pilot DAR]

An effort to preheat the engine the engine will be well worth it both in easy, safe starting, and long term engine life. Just think of your really expensive crankshaft, camshaft and lifters running with little or no lubrication for the first 30 seconds, while that thick oil is being warmed up enough to flow to where it is needed. If you have any doubt, watch how much longer it takes to get an oil pressure indication after a very cold start. That's how long the engine is running with very little lubrication.

It's easy to get the engine running and be so pleased with yourself, that the damage just done to the engine is forgotten - until "making metal" time.

If you just have to fly, with the aforementioned care around propellers considered, prime it and pull in through 5 to 10 times, and then prime and repeat, prime and repeat, until you've pulled it through 30 to 50 times. If you still want to go flying after that, it should start fairly easily. The oil will have started to warm a little and flow, and the priming will have introduced a little bit of oil dilution into the cylinders to reduce the friction and stiffness. This has worked for me numerous times in the cold Canadian winters.

Cheers, Pilot DAR

[SNS3Guppy]

I have found that a C182 (old one with 12v system) starts easily in just above zero deg weather if you pull the prop through a couple of times before starting.


Pulling it through doesn't accomplish anyting that improves starting...no limbering oil up, no forcing oil through system, no making the engine easier to turn...the only thing you might be accomplishing is turning the propeller until the engine is on the impulse coupling before cranking.

In my particular case, no primer at all needed, just a few quick squirts with the throttle while engaging the starter.


The throttle is nothing more than an air valve. Some throttle systems use accelerator pumps. These are not for priming. The accelerator pump is designed to aid in engine acceleration during rapid throttle movements. The primer is for...priming.

If you just have to fly, with the aforementioned care around propellers considered, prime it and pull in through 5 to 10 times, and then prime and repeat, prime and repeat, until you've pulled it through 30 to 50 times. If you still want to go flying after that, it should start fairly easily. The oil will have started to warm a little and flow, and the priming will have introduced a little bit of oil dilution into the cylinders to reduce the friction and stiffness.


You're not diluting anything by doing that. What you are doing is removing any oil on the cylinder walls and drastically increasing wear, as well as increasing your liklihood of having a fire.

Preheat, preheat, preheat. Pulling that prop through isn't limbering anything up.

Oil dilution is an older system included as a factory option going back to the second world war, in which fuel was introduced directly into the oil on shutdown. The benifits were found to be nil, and it's been history for a long time now. You're not going to dilute the oil using the prime...in fact, you're not diluting anything. What you are doing is moving parts without adequate lubrication, when it's needed most Most wear occurs on engine start, and you're increasing the wear by a considerable margin.

[Saab Dastard]

watch how much longer it takes to get an oil pressure indication after a very cold start

This interests me - on my car, I notice that the oil pressure remains at max until the oil has warmed up and has "thinned". Only then does the oil pressure reduce at lower revs.

I guess it depends on how and where the pressure is measured.

SD

[denhamflyer]

I have had my fuel injected 182 for a couple of years. I find that if it is very cold then double prime. i.e. fuel pump on, full fuel, watch fuel flow,shut off, pump off then repeat - works everytime.

You may also have the thottle too open or closed. I find more open for hot start and slightly less for cold. But all in all it is very tolerant.

[flyme273]

Quote:
watch how much longer it takes to get an oil pressure indication after a very cold start
unquote

Something wrong here. Oil pressure should rise within 30 secs.

The concern in cold weather is excessive pressure as warned by Lycoming, wait for longer time for oil to warm at low rpm's (lean engine to avoid plug fouling). At power checks watch the oil pressure when increasing throttle - do not allow it into the red sector. Excessive pressure will cause damage.

Also in car, drive at low rpm until warm.

[172driver]

The concern in cold weather is excessive pressure as warned by Lycoming, wait for longer time for oil to warm at low rpm's (lean engine to avoid plug fouling). At power checks watch the oil pressure when increasing throttle - do not allow it into the red sector.

My experience entirely. After a cold start, it takes a while for the oil pressure to decrease while the oil warms up.

[RatherBeFlying]

I flew into Sudbury, Ontario one fine March day in Toronto. Taxiing in, I noticed that every airplane parked outside in the snow had an engine blanket and an extension cord running to an outlet:uhoh:

Came back a couple days later and applied preheat for half an hour -20C.

Remember you're using low density air to warm high density metal.

After my first abortive attempt, the mechanic worked the prime and the apprentice pulled the prop through exactly as described by PilotDAR.

The people I rent from keep their a/c in the hangar and put on engine blankets immediately after shutdown.

[LowNSlow]

flyme273 I think the point is that cold straight (multigrade is better) oil is much more viscous when cold and is slower to reach the bearings etc down convoluted passageways than hot oil. This exposes the wearing surfaces to greater friction at initial start up.

[sternone]

I find more open for hot start and slightly less for cold

This is strange, for me in the C152 it's the opposite! When the engine is hot i start with trottle closed and when it fires up i open it slightly, works for me all the time.

[Crosshair]

Your aircraft is obviously defective. Best sell it now for whatever price you can get. I have a 1991 Toyota to offer in trade. PM me to arrange the swap!

[toolowtoofast]

I would recommend an oil or engine warmer - there are dipstick elements available, however an engine blanket is probably better, as it warmes the whole engine, not just the oil. Have a timer on it, or just turn it on the night before you want to go flying. Even a small bathroom-type fan heater will make a difference!

As for starting cold - easy to overlook is having the mixture closed during fuel pump prime (no fuel!) I fly an injected 550 C185, and it starts within 3 to 5 blades even when it's below zero ambient, with a 4-5 second prime (that's 4-5 seconds of positive fuel px).

[SNS3Guppy]

There's no substitute for a proper preheat in cold weather. Not just the oil; the entire powerplant.

[Scottishflyer182]

Update. Tried it this morning with the Engineer at my side. Started no prob,

I must have flooded the engine.

:ugh::ugh::ugh::ugh:

[Floppy Link]

Now I've got my SEP IR back you'll have to take me up and show me what all those buttons and screens do!
Russell

[Scottishflyer182]

Hi Russell,

I'll have to learn to start it first.

Your welcome to come up any time. What would be an idea ......... a couple of ILS procedures at DND.

Swap seats and do a couple each.

colin

[yoohoo748]

In Northern Canada we rarely attempted to start anything without the engine being nice and warm with either a 'tanis' type heater or an electric car heater fan placed in the enging cowling. Engines were always covered with a blanket. I do remember once trying to start the islander when temp was a WARM 0 degrees C, and no luck what so ever. Put a blanket on it and a car heater inside the cowling, and we were in business.

Oil temp is an issue for obvious reasons. Another reason that was explained to me (not sure if true or not, but makes sense) was that Moisture is a natural byproduct of combustion, and any moisture that was left in the cylinder would turn to frost on the cylinder walls (causing wear) and most importantly for starting, on the spark plugs fouling the plugs, and thus not giving you any spark. Your best bet would be to be sure the engine is nice and warm (above 0c) before setting out for your adventures. Flying in the winter is great... Much greater performance at -30c then at +30c!!!

Have fun.

Yoohoo