Cold Operations and Misc

[dkenney1]

As a fairly new to me Taylorcraft owner, I have learned enough to have a few questions. N95938 is a 1946 BC-12D that during restoration has a C-85-12 installed. This spring and summer at between 2100-2300 rpm it trued and confirmed with GPS runs between 92 and 100 mph burning between 4.2 and 5 gallons per hour, so I think that's pretty good.

Sunday it was 27 degrees in the Buffalo area, severe clear, light crosswind and after two months of night flying the plane was calling me (11 year old son was calling my cell saying "Fly Taylor!!!). I installed the winter plate on the cowl and inflated tires.... first question what tire pressure, my POH, if can call it one is silent. They let me keep the plane in the museum part of the hanger, so very secure water tight and maintain 40-45 degree minimum temperature and it was 44 in there so I figured pre-heat not necessary, oil dripped as always. Once outside I spent more time than would have liked getting tail tied and wheels chaulked, and people talking and admiring my 8th coat of wax on it (son degreases and waxes the bottom every other flight). I'm new to handpropping so I am VERY scared I mean respectful of it. When starting my son is nervous too and asks for my cell, has 911 typed in and thumb above send when I get in front of the prop.

The plane that always starts the first time with one shot of prime took me an hour to get started. Maybe armstrong starters don't work as well in the winter? Is there any pointers for cold weather starts? I thought it needed more prime, mags off, one more shot and pulled blades through few times, but noticed small wet spot of fuel under the cowl, so it had fuel. Then figured I flooded it, so mags off, full throttle and pull prop through a million times until no more fuel dripping out (per the manual). Finally annoyed disgusted and fighting to keep blue words in my mouth, I told Ethan one last try or I'm putting this pig away. Of course that must be the trick because it fired up, instantly running smooth at 300 rpm and he yelled oil pressure 15 Dad.

I learned cold weather makes a big difference in flying qualities. I was having trouble staying below the 105 mph max level cruise speed even at 2100 rpm. Tail came up before had throttle all the way in and within two runway stripes was airborne and climbing strong with 18 gallons and 230 lbs of pilot/passenger meat. One thing I noticed was no matter what, I could not get the oil temp past the 130-135 degree range. Is that normal and more important okay? It seems low. Oil pressure entire flight stayed pegged at 32 psi.

I also learned about not having a mixture control can make cold weather operation something to think about. With throttle retarded and carb heat on the engine likes to stutter or even quit if advance the throttle, but pull back to idle it starts again. So winter flying for me means higher than normal approaches and judicious use of forward slip

At any rate we had a great time going from airport to airport getting used to cross wind landings on pavement (grass not an option with 2' of snow). The Tcraft is much more forgiving in a crosswind I think than the Champ I did my TW endorsement in, but I think the big Scott Tailwheel helps with that when you plant it.

Bored yet? My questions:
1. Cold weather start procedure?
2. Is 130 degree oil temp okay and if not what should I do to correct it? (other than go to Arizona of something I've read those threads LOL)
3. Tire Pressure?
4. Anyone have POH data that gives landing and takeoff data? Mine doesn't even say what best glide speed is

Thanks for the help/advice and for enduring my enthusiasm for the Taylorcraft.

Darrin

[M Towsley]

Re: Cold Operations and Misc

Hi Darrin,

Lot of your questions have already been posted over many years. Just use the search button and you may get a quicker answer.

I use two shots prime, (mine is an A-65), four blades and starts every time. Not sure what the problem with yours is but I am sure others will chime in.

Mixture on the Stromberg does not really take effect until you are about 5,000 feet and above. Your idle mixture is probably off. Colder air means more oxygen, less fuel so you may have to bump up the idle mixture 1/4-1/2 turn. Each engine seems to like different settings. What fuel, mogas or 100LL? Mogas seems a little more susceptible to cold issues.

Tire pressure is 20 psi, but you will have folks talk about the merits of lower pressure, higher pressure, etc. This is for the stock sized tires.

I can barely get my engine to 170 in the summer. In winter I block off the lower cooling intake as you did. I am experimenting with slightly taping my main air cooling grills. The Alaska guys seem to do this with no problem, it makes me nervous so I am only taping a little off.

I use 65 mph for best glide, but each airplane is different.

I am sure others will chime in. Good luck!

Oh, and one other thing. It seems you have a healthy respect to hand-propping, nothing wrong with that. You will be more comfortable as time goes on. Instead of having 911 ready to dial, make sure your son knows how to stop the engine and/or throttle back in case the throttle is set too high. Can he reach the brakes, show him how to apply and hold them. At startup I only have a little throttle applied, this seems important with my particular engine, and for that matter the other two A-65's in my other two T-Crafts. Hand propping is making sure you do the same thing EVERY time. Miss a step and it could be bad. Make sure you do it the same every time. Tie the tail, or chock, set brakes, mags off, throttle closed, prime, four blades, mags on, throttle slightly opened, check aircraft movement/brakes set, prop. Some people leave the fuel off, I find that not helpful as there is enough fuel to get the aircraft quite far enough to run into something and if you forget to turn the fuel back on it will die and you will be back at step one.

[crispy critter]

Re: Cold Operations and Misc

I agree with Marty on all he said. I use 18-20lbs psi in the tires. Seems to work well for all taylorcrafts with standard 600x6 tires. Fuel drip is normal newrly anytime you prime a 4 cyl continental. Just don't over do it.
Most of these old brids are a bit cold natured, especially in cold weather. Sometimes they will start and die and few times before getting enough heat in them to stay running unless ya do a high idle start which I never recommend no matter the circumstances. However there is one thing you said that I think might be an issue....you said it was idling smooth at 300rpms, that's a little on the low side. You should be idling around 500rpms(+/- 100rpms). Ya might wanna pick the idle up slightly.

Also, a very big DIDO on teaching the kid how to shut down the mags and how to work the brakes just in case.

[paulnuss]

Re: Cold Operations and Misc

I'll agree with all said so far, and add the use of carburetor heat to be necessary to keep the intake temperatures up when throttled back even a little bit. On the little Continentals, that carburetor is down in the cold air, and evaporating gasoline, a significant cooling process, and chilling the whole intake system, to the point that the fuel condenses out of the fuel-air mixture and mostly air is getting to the cylinders when the air temperatures are quite cold. The gasoline has condensed out onto the intake tubes and is dripping downwards. The engine can lean out and quit with small throttle opening. I'll pull carb heat on when still at cruise, while exhaust pipes are hot, to warm the whole intake up some. I still keep extra throttle on the approach, keep close enough to the runway to land even if the engine quits, and add drag by slipping as necessary to keep the chosen glide path. The extra momentum of a heavier metal prop helps keep the engine spinning; I have experienced the engine stopping completely with a wood prop. The Alaska tribe members can probably add to all this. I wouldn't worry about the "maximum level-flight cruising speed", as long as the air is smooth. My limitations have always been being able to board the airplane when wearing enough clothes to keep from freezing in the cockpit when it's really cold out!

[M Towsley]

Re: Cold Operations and Misc

As a side note, I recently picked up a 1947 copy of the Operator's Handbook for A and C series 4 cylinder engines. One page has a lot of good information.

Along with telling you how to start it there is a good section on warm-up. It states to not allow the engine to operate at more than 800 rpm for the first 60 seconds after starting. Especially important during cold weather as the lubricating oil will be slow in circulating. Then after two or three minutes running at 800 rpm increase throttle gradually until rpm is between 1200-1500 and allow to run for 3 to 5 minutes depending on atmospheric temperature. This time may be used in taxing, (sp), to point of take-off.

I did not note your engine idle rpm, that is very low as pointed out. Some guys like them low but never that low. Usually you would be clicking the impulses if you have them. My oil pressure is more like 30 on start-up and during cruise is around 35 psi. I would think your cold oil pressure should be higher than 15 psi, just a thought.

Also, please go to this thread about cold weather ops, look for the pdf. I posted: http://vb.taylorcraft.org/showthread...ental+bulletin

[astjp2]

Re: Cold Operations and Misc

5-6 shots of primer to start with, you may need more, 160 oil temp minimum for 1 hour to clear out the moisture from inside the engine, tire pressure is enough to keep the tires round, I run 12 psi but have tundra tires, no such thing as a POH, they use placards. This is no Cessna so don't have the same assumptions or expectations as you would with this airplane....as a 150. Listen to what the experienced people have to say and you will do good to stay safe. Tim

[dkenney1]

Re: Cold Operations and Misc

Thank you everyone for the information and advice. My son definitely knows how to close the throttle and switch the mags off and we have practiced. He's short but can stand on brakes, however I have all wheels chalked and the tail tied. He also knows NOT to get out if the engine is running, and as soon as a prop the engine and step away I go to where he can see me. That way if engine starts and he doesn't see me he shuts it down. He also knows how to tune the handheld radio to emergency and rochester approach if needed, hold heading and altitude. On calm day and grass runway he has 3 point landed quite nicely with only minimal assistance from me on rudder pedals once on the ground. He definitely would not have bent anything. I'm fortunate my wife likes to fly too (she actually bought the plane) but doesn't desire to take the controls.

As for temps, it was also recommended that I block maybe half the vents I have at the bottom of the cowl for exit air. I don't know if standard or not, but I have 6 rows the width of the bottom cowl of louver type vents plus the 2" tall opening at the back of cowl where it meets the firewall. I was advised by my A&P/AI to be careful taping the front grill since want to keep the cylinders with cooling air

Thanks again,

Darrin

[Robert Lees]

Re: Cold Operations and Misc

Your kid sounds quite switched on. Good for you, and him.

Rob

[n6346m]

Re: Cold Operations and Misc

Darrin,
I'm sure by now you have read previous posts about these subjects. It seems like every time an old subject is brought up some new information surfaces. I understand your concern about low oil temperatures in the winter. I have an open-cowl L2 where half the engine is sticking out in the breeze. I have read all I could about getting the engine oil to run warmer in this forum the J3 forum and any other place that I can find. Here is what I have done:
I have had an oil tank cover made out of good insulating material (like the new high-tech thin engine covers not the thin cheapies you get at Wag-Aero). I use a wood prop. I made a plate to partially block the air coming OUT of what passes as cowling between it and the boot cowl. I think it may help keep some of the warm air inside the cowling (kind of like a poor man's cowl flaps) and avoid some of the hotspots created by blocking the INLET. I have blocked off the oil tank cooling air where it comes in from the nose piece.
Having done all that, I can say that the last time that I usually see the oil temp gauge come off its lower peg (100F) is sometime in September and the next time I see it move will be sometime in May. Yes, the gauge has been checked out.
The good news is that with all that still in place during the summer, I have seen the temperature reach a whopping 170 degrees. The best I can do is to try to mitigate the effects of moisture in the oil by changing the oil frequently, using oil with good anti-rust properties, and adding a treatment of Camguard.
As far as hand propping, there are probably as many techniques as there are hand-proppers. For one thing each airplane is a little different. I have always been a firm believer in starting the engine with the fuel valve turned OFF. There are two reasons why. The only reason you tell the person in the cockpit to hold the brakes and show them how to kill the engine is in case something goes wrong. If your airplane starts normally and is idling it's not going anywhere, even if it's not chocked or tied down. I agree with Marty that the engine will run a long time at idle (about 30 seconds) but at higher power settings it will use up that gas pretty quickly. I have heard of more than one airplane going flying without its pilot after hand-propping. Even if you normally start on a crowded ramp or between hangars its a good habit to get into because you don't always have the luxury of starting from home base. I heard a story (don't know if it's true) about a guy who started an engine that had been flooded and got distracted and forgot to pull back the throttle to idle after clearing the engine. Once it fired he got out of the way and was able to grab his right wing strut and it went around in circles until the carb bowl ran dry. He was glad he didn't have to hang on for 12 gallons worth. If you're on floats and skis you really want to get into the habit of turning off the fuel valve because it can be a long way to swim if you don't.
The other reason why I always turn off the fuel valve is that I am blessed with a Stromberg carburetor that sometimes it decides it wants to drip and sometimes it doesn't. In both my old 65 and my upgraded 90 I could NEVER get the engine started as long as fuel was dripping out of the carb air box. Turning off the fuel valve prevents the fuel bowl from overfilling and flooding the engine.

[n6346m]

Re: Cold Operations and Misc

Sorry OOPS double post

[dkenney1]

Re: Cold Operations and Misc

Your kid sounds quite switched on. Good for you, and him.

Rob

I'm old school, I don't think "child labor" a bad thing. LOL

[c tudor]

Re: Cold Operations and Misc

Further question on cold starting. ( well cold for UK at around 35* F, not Alaska cold).

Today we had a flour bombing event at the local field. A few A65's started and then died after a few seconds, as Kevin says, until warm enough to run properly and were then fine.

A couple of C 85's didn't want to play at all though. Discussion broke out. Some say it's lack of fuel, as it condenses out before it gets to the cylinders, others that once the plugs are wet with fuel you have no chance until they dry. At least a hot flooded engine will dry out better than a cold one as the fuel will evaporate easier.

Usual flooded technique didn't work, that's for sure. One eventually started after being sworn at and the left in disgust for a few hours.

My money is on wet plugs. Certainly seemed that if you didn't get it just right first time you were in for a sore arm.

Any thoughts and suggestions?

Happy Chistmas,

Chris.

[c tudor]

Re: Cold Operations and Misc

Further question on cold starting. ( well cold for UK at around 35* F, not Alaska cold).

Today we had a flour bombing event at the local field. A few A65's started and then died after a few seconds, as Kevin says, until warm enough to run properly and were then fine.

A couple of C 85's didn't want to play at all though. Discussion broke out. Some say it's lack of fuel, as it condenses out before it gets to the cylinders, others that once the plugs are wet with fuel you have no chance until they dry. At least a hot flooded engine will dry out better than a cold one as the fuel will evaporate easier.

Usual flooded technique didn't work, that's for sure. One eventually started after being sworn at and the left in disgust for a few hours.

My money is on wet plugs. Certainly seemed that if you didn't get it just right first time you were in for a sore arm.

Any thoughts and suggestions?

Happy Chistmas,

Chris.

[Scott]

Re: Cold Operations and Misc

Couple of things I can think of:
as the temperature drops air becomes more dense which tends to lean the air-fuel ratio all else being equal. If the idle mixture is set on a hot day, the engine may not idle on a cold day, especially at initial start when the engine generally needs a bit richer mixture anyway. So... if the engine fires and then dies in the cold, it may be too lean. One way to get past this is to give an extra shot of prime after the engine starts.

I suspect the engine wasn't flooded, but if it was, one option to clear the combustion chambers is to turn it over backward (mags off of course). I used to hand prop a turbocharged Pitts S1. Injected lycomings are not the easiest to start at the best of times and hand proping an injected engine can be work to say the least. Pulling the prop through backward was really the only way of clearing a flooded situation.

Sounds odd but basically once an engine is flooded, the combustion chamber and most of the intake system will be soaked in fuel. Each time you turn the engine over in the correct direction, more fuel gets drawn into the combustion chambers.... to much fuel + no enough air = no fire. When you pull the engine over backward, air is drawn from the exhaust and you end up with a combustible mixture in the combustion chamber. Then mags on and go for the start. You may find it fires but then quits again immediately, this is because more over rich mixture has been drawn into the combustion chamber and snuffed out the fire. Repeat the backward clearing process and try again. With the Pitts it wasn't unusual to have to do this 3 or 4 times to get it going. With the small continentals it should be much easier. If the motor doesn't at least fire after pulling it through backward, it's probably not flooded.

another thing that can happen in the "right" conditions (you probably weren't cold enough), engine fires enough to condense moisture in the combustion chamber, which then freezes/shorts the spark plugs. Time and heat is what's needed now.

[Pearson]

Re: Cold Operations and Misc

Chris,

AS you probably already know, these little Continentals all start differently. Also, during cold weather many operators turn the idle mixture screw OUT about a 1/4 of a turn, and then turn it back in when the weather warms up in the spring.

During cold weather starts instead of cracking the throttle open an eighth of an inch, pull it ALL THE WAY closed. When it fires, IMMEDIATELY bump it in about a SIXTEENTH of an inch. Let it idle for a minute before you try to add throttle. Another trick I have used on a FEW engines is to start with the carb heat on. I am not sure of how or why it works, but I have seen it make a difference on some engines. After it idles for a minute, turn the carb heat off.