Scary moment today

[par]

So after a month in the shop, I got my mooney back yesterday. It was in the shop for several small issues that were resolved. The temp was about 46 degrees yesterday and I figured it was good enough to skip preheat. I tried to start it myself with the standard procedure of 3 pumps to prime the engine but did not have any luck after several attempts. So I ended up calling the mechanic over and he recommended I pump the throttle a couple time as the engine is cranking. Sure enough, it worked and the engine came to life. We ended up taking her out for a quick flight and all was well when I landed.

Then came today with a planned trip up to NY. The temp today was 26 degrees when we arrived at the airport. My plan was to have the FBO preheat the engine since I do not own a preheater myself. It turned out the FBO has no capability to preheat. So, against my better judgment, I decided to go ahead and try a cold start. I followed the same procedure as yesterday by priming it 3 times and pumping the throttle some as the engine cranked. Once again I tried several times and the engine would fire but not start. After having no luck, I decided to put the plane back in the hangar. When I got out, I noticed there was fuel dripping on the front tire from a small drain in the cowling. I figured it was overflow from the carb from trying so many times. Before pushing the plane back in, I though let's try just one more time. Apparently this was a bad idea. I tried once again but I had no luck. I then got out and as I walked to the front of the plane, I noticed smoke coming from the air filter. Soon after that I saw flames under the cowling in between the nose gear doors. I immediately called 911, grabbed a fire extinguisher(empty) and called the FBO guys over to help. The fire must have lasted for about a minute but extinguished itself.

So, now I am trying to figure out what I did wrong. I must admit I have very little experience with carbureted piston engines so I was following the advice of the shop. Obviously I will not be flying it until they look and see what needs repair. However, I do want to know if it should be this difficult to start in the cold. If so, how in the world do you take this plane anywhere when you can't event count on the engine to start if the temps drop below 40. I kind of wish I had a fuel injected mooney right now. I am definitely got to get a preheater as well before I fly again. It was a very scary situation that luckily did not go south.

[Hank]

I hope there was minimal damage from the fire!

 

This is what my Owner's Manual says about cranking my C.

 

Good luck with your. Hope the rest of your ownership experience is more pleasant. I have an oil sump heater and carry an extension cord with me to plug in when I travel, but it's not always possible. Only takes about an hour, but I leave it plugged in overnight when I can.

[Marauder]

So after a month in the shop, I got my mooney back yesterday. It was in the shop for several small issues that were resolved. The temp was about 46 degrees yesterday and I figured it was good enough to skip preheat. I tried to start it myself with the standard procedure of 3 pumps to prime the engine but did not have any luck after several attempts. So I ended up calling the mechanic over and he recommended I pump the throttle a couple time as the engine is cranking. Sure enough, it worked and the engine came to life. We ended up taking her out for a quick flight and all was well when I landed.

Then came today with a planned trip up to NY. The temp today was 26 degrees when we arrived at the airport. My plan was to have the FBO preheat the engine since I do not own a preheater myself. It turned out the FBO has no capability to preheat. So, against my better judgment, I decided to go ahead and try a cold start. I followed the same procedure as yesterday by priming it 3 times and pumping the throttle some as the engine cranked. Once again I tried several times and the engine would fire but not start. After having no luck, I decided to put the plane back in the hangar. When I got out, I noticed there was fuel dripping on the front tire from a small drain in the cowling. I figured it was overflow from the carb from trying so many times. Before pushing the plane back in, I though let's try just one more time. Apparently this was a bad idea. I tried once again but I had no luck. I then got out and as I walked to the front of the plane, I noticed smoke coming from the air filter. Soon after that I saw flames under the cowling in between the nose gear doors. I immediately called 911, grabbed a fire extinguisher(empty) and called the FBO guys over to help. The fire must have lasted for about a minute but extinguished itself.

So, now I am trying to figure out what I did wrong. I must admit I have very little experience with carbureted piston engines so I was following the advice of the shop. Obviously I will not be flying it until they look and see what needs repair. However, I do want to know if it should be this difficult to start in the cold. If so, how in the world do you take this plane anywhere when you can't event count on the engine to start if the temps drop below 40. I kind of wish I had a fuel injected mooney right now. I am definitely got to get a preheater as well before I fly again. It was a very scary situation that luckily did not go south.

Not a good situation, but hopefully nothing burnt. Even fuel injected planes can be hard to start and will flood. A few years ago after a cold start, the guys on the Unicom said I gave them a great flame show. As I was starting, it backfired once and then started. Apparently that backfire was a fireball that came out the exhaust and I found soot on the area above the exhaust pipe and on the cowl flap.

Pre-heating helps a lot. Anytime I am below 40, I find my cold starts much easier when I pre-heat.

[cloud116]

Like Maurader, my cutoff for cold starts is 40f. I fly in cold weather quite frequently and, as you point out, it is extremely frustrating to have to always make sure you have access to either an outlet or an FBO with pre-heat capability (and I hate the cost of the FBO option). After dealing with that for a couple years, I bought a Honda 2000 generator and it is worth the $900 and 50lbs. The unit has a great fuel ap that can be sealed, and I have never had an issue smelling fuel. It runs my tanis engine heater and my cabin heater. It does not take long and I climb into a warm cabin and start a warm engine. Love it.

[HRM]

If so, how in the world do you take this plane anywhere when you can't event count on the engine to start if the temps drop below 40. I kind of wish I had a fuel injected mooney right now. I am definitely got to get a preheater as well before I fly again. It was a very scary situation that luckily did not go south.

 

It's the engine, not the Mooney. I would not be surprised if these issues exist in other planes using the same power plant. Not to rub salt in the wound, but my E started today in less than a blade--in fact, it started so quick it gave me pause. Of course, come the heat of the summer you will see the fuel injected guys posting as they try to find that magic sequence that gets a hot E to start before the battery is toast 

[Seanhoya]

Par,

 

I echo the previous comments, and BTW - I am in the DC area, so I am dealing with the same weather issues right now you are.  I preheat to 40 degrees in my carbuerated 1968 M20G.  My technique on a really cold day is four pumps of the throttle without the fuel pump on, then turn on the fuel pump and crank to engine.  Sometimes, you have to lean the mixture as it starts to turn over.  

 

I don't rely on FBOs to know the slightest thing about preheating.  I have an oil sump pad and carry a 100' extension cord.  Usually an hour is all it takes to bring up the temp to 40 degrees.  I worry more about engine wear and tear than actually getting it started in the cold.  

 

Oh - one more thing.  Technique only.  Make sure the master power is off and the front wheel chocked, and hand-crank the prop three times.  I do this religiously now, even in warm weather.  Anecdotally, it "loosens up" the oil and engine parts.  In practice, I have no idea why this helps start the engine, but it does!

 

Clear Skies!

 

Sean

[rbuck]

+1 for Sean's suggestion. I do the same.

[par]

I had always heard that carbureted engines are hard to start in the winter but I never imagined it would be this hard. I picked this plane up in Portland, ME on a 26 degree day but they had preheat available and it started without much trouble. I also remember flying Cessna 172's years ago and starting them in similar temps outside where they were normally parked and never had an issue. 

 

I have been scouring the internet today to find the correct technique and I have found many. Until I can find one that works for mine, i'm going to be on edge each time I attempt to start it. What do you guys recommend for an electric sump heater? Is this something that can be easily(cheaply) installed? When operating from home, I plan to use another self-engineered heater but it will not be practical away from home.

[par]

Par,

 

I echo the previous comments, and BTW - I am in the DC area, so I am dealing with the same weather issues right now you are.  I preheat to 40 degrees in my carbuerated 1968 M20G.  My technique on a really cold day is four pumps of the throttle without the fuel pump on, then turn on the fuel pump and crank to engine.  Sometimes, you have to lean the mixture as it starts to turn over.  

 

I don't rely on FBOs to know the slightest thing about preheating.  I have an oil sump pad and carry a 100' extension cord.  Usually an hour is all it takes to bring up the temp to 40 degrees.  I worry more about engine wear and tear than actually getting it started in the cold.  

 

Oh - one more thing.  Technique only.  Make sure the master power is off and the front wheel chocked, and hand-crank the prop three times.  I do this religiously now, even in warm weather.  Anecdotally, it "loosens up" the oil and engine parts.  In practice, I have no idea why this helps start the engine, but it does!

 

Clear Skies!

 

Sean

 

Sean, 

 

How much do you lean by? I will def hand turn the prop a few times. I have read that on several other forums as well.

[bonal]

Lots of advise on best way to start a cold Mooney in fact my searches on Google on how to better start my mooney on a cold day was what led me to Mooneyspace. Here is what works for me on the below 40 degree days. Like others I always pull the prop through a few times even on hot days. When really cold mixture forward boost pump on note pressure 4 full pumps throttle boost pump off let sit at least 30 seconds crack throttle crank starts on 2 or 3 blades every time. Before I got the hang of it I too was very frustrated You will find your technique and this will be a distant memory

[yvesg]

This is what I use to pre-heat. 35 000 BTUs. I never assume the FBO where I park or where I go will have the equipment I need to pre-heat. This way I am always OK.

Yves

[Hank]

In cold weather, regardless of preheat:

- turn prop a couple of revolutions, stop on compression stroke

- fuel pump on until fuel pressure stabilizes, then pump off

- mixture rich, pump throttle 3-5 times

- plug in headset, wind & set clock, kill 30/45 seconds while the cold fuel slowly vaporizes in the carb

- turn key and push.

This will usually fire in 2 or 3 revs, but may take several to catch.

The colder the weather, the more throttle pumps and longer wait time. The engine heater only heats the engine, not the fuel tanks; mine only heats the oil sump, but in a hangar the whole engine compartment will be warm.

[par]

Hopefully someone will chime in but I think the fire may have started inside the air box as a result of backfire. The reason why I think this is due to the smoke coming directly out of the air filter. Hopefully I can get an answer next week of what may have happened but this is what I am suspecting at this point.

[aaronk25]

On a carb carb automobile when you pump the gas the spray of fuel goes down the manifold.....On a plane the carb is upside down on the bottom of the engine and if pumped without cranking the engine the fuel runs out of the carb down inside the airbox/carb.

The easy way to stay a carb plane and be darn sure it's not flooded is to never get it flooded. Just crank the starter (at this point it lean and no fuel is present then pump the gas while cranking once enough fuel reaches the cylinders it will fire and there is no chance of it getting flooded.

I keep pumping the damn throttle until it starts. It's next to impossible to flood a engine from pumping/priming while there engine is cranking.

Hope that helps. But never ever EVER EVER pump the throttle on a plane without cranking the engine while doing so. All that has to happen is have the engine backfire out the carb and your on fire if fuel is laying in airbox/cowl dripped all over tire!

[Hank]

Sorry, Aaron, but my Owners Manual specifically says to pump the throttle before turning the key. Once or twice for Normal starts, 3-5 times for Cold starts. I trust Mooney, who wrote the instructions, more than I trust your fuel-injected wisdom for starting my carbureted engine. Thanks anyway, though!

[larryb]

Reiff pre heater and a cell switch!

Sent from my iPad using Tapatalk

[Hank]

Reiff pre heater and a cell switch!

Sent from my iPad using Tapatalk

That helps a lot! I have one of Philip's, and love it. But you still need the cold start procedure, as only (part) of the engine is warm. The fuel is certainly c-o-l-d. Give it time to vaporize before turning the key. This worked well for me living on the Ohio River for seven years, and it still works for me in the Deep South, it's just not as cold or snowy.

[HRM]

 

...and hand-crank the prop three times.  I do this religiously now, even in warm weather.  Anecdotally, it "loosens up" the oil and engine parts.  In practice, I have no idea why this helps start the engine, but it does!

 

 

After an engine, or any other kind of mechanical device (gear boxes, mechanisms, etc.) sit for a bit the parts develop what is called stiction, which is:

 

the friction that tends to prevent stationary surfaces from being set in motion.

 

This is exacerbated by the oil, which has cooled and become almost glue-like. A nice, slow turn, relatively speaking against the speed of engine normal operation, releases the stiction and gets the oil flowing a bit. Especially good when the machine is cold, still a good practice when weather is warm.

 

Also, think about the starter. You want to turn the engine just past the compression point. This makes it easier for the starter to overcome the initial rotary inertia that makes it's job much easier and reduces start-up stresses significantly.

 

Be at one with your aircraft, feel what it feels, spend the time to treat it as if it were alive. The joy of flight awaits.

[bonal]

Sorry, Aaron, but my Owners Manual specifically says to pump the throttle before turning the key. Once or twice for Normal starts, 3-5 times for Cold starts. I trust Mooney, who wrote the instructions, more than I trust your fuel-injected wisdom for starting my carbureted engine. Thanks anyway, though!

Agreed

[carusoam]

Summary of what works...

(1) fuel needs to evaporate. Warmth and time are required. Less warmth, more time. Excess pumps is a bad substitute for no warmth.

(2) 100LL needs temps above 20°F.

(2.5) Between 20 and 30°F it is possible to pump enough fuel to possibly get it started with increased risk.

(3) the colder it is, the more pumps it takes. More pumps to give the same vapor equals excess fuel down the drain...

(4) pre-heat is magic. Get a version of one. Heat the oil, heat the air intakes...

(5) throttle pumps without turning the engine begin to drain onto the tire.

(6) turning the engine doesn't allow time for the fuel to evaporate.

(7) in a C, the intake tubes run through the oil sump for a reason.

(8) pre-heating the oil is a nice way to preheat the intake tubes.

(9) warm air preheat, nicely heats the intake tubes.

(10) fuel draining on the tire is a dangerous situation.

(11) from your initial training, in the event of a fire, continue to start the engine.... (Nice advice for the type of fire the OP had)

(12) over priming an FI engine has the same drain hole that leads to a similar danger of fuel everywhere....

These are ideas that I came up with from having my C outdoors for a decade...

By the time I saved enough money to buy a personal propane preheater I bought a different plane...

Go electric preheat if you can. The ability to call on the cell phone for pre-heat is magical.

Try not to complain about carb'd engines... The guys in Wisconsin are dealing this in there everyday modern automobiles. Ever have to go start your car at lunch time to warm it up so it will start at the end of the day?

Preheat, pump, wait, start...

Best regards,

-a-

[aaronk25]

Sorry, Aaron, but my Owners Manual specifically says to pump the throttle before turning the key. Once or twice for Normal starts, 3-5 times for Cold starts. I trust Mooney, who wrote the instructions, more than I trust your fuel-injected wisdom for starting my carbureted engine. Thanks anyway, though!

Hey Hank, your 50 year old manual is wrong. Good way to catch on fire. I think the OP proved that. Like many on this forum I've spent my share of time in archers and 172s and 182s....with "upside down carbs. Pumping then without cranking leads to fuel in places where Fire isn't wanted.

So I respect you, and mooney but let's see if we can come up with a way of starting these old engines that doesn't result in starting on fire if primed excessively....

I also live in MN...got my share of cold starts......

[Guest]

It's not the engines fault, its the airframe. Mooney never installed a primer system like almost all other manufactures did. Pre-heating certainly will improve starting, as will a warm battery.

Starting with cold cylinders leads to scuffed piston skirts

Clarence

[Hank]

My Mooney cranks like my old truck--step on the gas a couple of times then turn the key. This won't work on fuel injected trucks or Mooneys.

The OPs situation was unfortunate AND unusual. It may be more common in Cessnas and Pipers, I don't know, but their induction systems are different from ours (par's and my own; injected Mooneys are a completely different animal).

Without pumping the throttle, we will be cranking an engine with no fuel, a losing proposition. No primer, remember?

[Yetti]

One thing my dad always told me was (After working and racing high horsepower ski boats)   If you see fire, keep cranking.   Hopefully it will suck the fire into the carb

[Mooneymite]

One thing my dad always told me was (After working and racing high horsepower ski boats)   If you see fire, keep cranking.   Hopefully it will suck the fire into the carb

If you become aware of an intake, or stack fire during start:

Continue cranking. If the engine starts, let it run.

If fire doesn't go out quickly:

Mixture cutoff.

Continue cranking.

If fire still doesn't go out:

Evacuate, evacuate, evacuate.