Winter warm ups

[EricJ]

1 hour ago, steingar said:

Car engines haven't got a lot of aluminum in them because it's expensive.  No differential cooling, so things still fit in the cold.  There are other issues like oil viscosity, but you can't break a car engine starting it in the cold.

Cars have had aluminum heads and/or aluminum blocks for a long time.   Anything from little four-bangers to big V8s.   They start in the cold just fine.  

 

[ArtVandelay]

From what I have read, the "piston to cylinder clearance" problem is much worse on an air cooled engine than a water cooled. Thus the need for preheat. Maybe someone else can elucidate.

I’ve read that engines that are run WOT requires greater clearances as do air cooled engines due to uneven cooling. But it seems to me that greater clearances means no worries on cold starts. Tight clearances would require preheating.


Tom

[carusoam]

The biggest temp variation challenge occurs at the pistons and cylinders.... after start...

Jamming the piston crowns into the cylinder choke sounds like a possibility...

The gap is so big, we get a yellow and green range on the CHT gauge to keep us from messing things up.

 

A reminder to use caution when starting... don’t for get the throttle.   

Accidental High power, high rpm, during start-up is a technique to avoid...

PP thoughts only, not an engine designer...

Best regards,

-a-

[EricJ]

1 hour ago, ArtVandelay said:

I’ve read that engines that are run WOT requires greater clearances as do air cooled engines due to uneven cooling. But it seems to me that greater clearances means no worries on cold starts. Tight clearances would require preheating.


Tom

The clearances in the Formula 1 internal combustion engines these days are tight enough to require heating to around 180F before a start is attempted.

https://formulaoneinsights.com/2-formula-1-engine-start-up-procedure/

Air-cooled boxers don't seem to have that kind of trouble.

 

[M20F]

6 hours ago, ArtVandelay said:

I never preheated my car when I use to live up north, if traveling and you flew the previous day or two, do you really need to preheat?

 

 

Tom

The viscosity of car oil (low) and airplane oil (high) is the primary difference.  

[Ragsf15e]

7 hours ago, ArtVandelay said:

I think almost every modern automobile engine today is aluminum (block & pistons)to save weight and improve fuel mileage, even trucks and diesels use aluminum. I’m wondering if this isn’t more urban mythology. I’m not talking severe cold ( less than 20°F) and as I said, been recently flown.

 

Tom

 

That ain’t severe.  That ain’t even cold!  

I use a SIM card enabled socket to start a cheapo electric space heater set on low.  Heater has a dryer vent attached and shoved into the cowl flap.  Generally run it from bedtime the night before flying.  Blanket on top the cowl.

Go out to start the airplane at 10deg f and the oil, cylinders, etc is at 60 deg +.

Lycoming recommends preheating below 20deg f, I do it anytime below 40.  It doesn’t hurt anything and it starts easier/smoother.

[Sandman993]

On 12/13/2019 at 1:45 PM, ArtVandelay said:

I think almost every modern automobile engine today is aluminum (block & pistons)to save weight and improve fuel mileage, even trucks and diesels use aluminum. I’m wondering if this isn’t more urban mythology. I’m not talking severe cold ( less than 20°F) and as I said, been recently flown.

 

Tom

 

I think it’s the steel barrels in the cylinders with aluminum pistons rubbing against them. Mike Bush says it’s almost criminal to start an aircraft engine below 40f. 

[Sandman993]

I too purchased a sportsman generator for away trips, to warm up a bit on a cold ramp where electricity wasn’t available.

Typically, I run it once a month at the hangar just to keep it, well, runnable.

somehow, it’s stopped fueling and I can’t get it going. Full disclosure, I put av gas in it. Anyone have an idea what I can do to to get it going again? The bulb pumps up fine. The spark plug fires but is dry. 
 

I was hoping someone else may have run into this and could offer a solution.

thanks in advance 

 

[neilpilot]

29 minutes ago, Sandman993 said:

somehow, it’s stopped fueling and I can’t get it going.

I know this is obvious, but are you sure your switching the Sportsman's ignition switch on the electrical panel ON? 

[Sandman993]

1 hour ago, neilpilot said:

I know this is obvious, but are you sure your switching the Sportsman's ignition switch on the electrical panel ON? 

Yessir... fuel vent to on, pump bulb, power on at the panel and the little knob next to the pull rope to on. Have started it a couple dozen times just to cycle it and typically run a fan or whatever for 15 to 30 minutes.

I checked for spark- ok

pulled plug, it looks great but dry. After a dozen pulls with the choke, you’d think it would be soaked.

was thinking perhaps the av gas may have damaged the diaphragm. Was hoping someone would have encountered this issue. The pump gas we buy has a short life span and I’m always afraid of it in components that don’t get used daily.

[PT20J]

 

2 hours ago, Sandman993 said:

Yessir... fuel vent to on, pump bulb, power on at the panel and the little knob next to the pull rope to on. Have started it a couple dozen times just to cycle it and typically run a fan or whatever for 15 to 30 minutes.

I checked for spark- ok

pulled plug, it looks great but dry. After a dozen pulls with the choke, you’d think it would be soaked.

was thinking perhaps the av gas may have damaged the diaphragm. Was hoping someone would have encountered this issue. The pump gas we buy has a short life span and I’m always afraid of it in components that don’t get used daily.

I doubt avgas is the problem. It’s the ethanol in mogas that’s hard on the diaphragms and nowadays most small engine carburetors have been designed to accommodate that. If it has compression and spark, then all that’s left is fuel. Some of these engines are easy to flood. I have had the cheap carburetors they use go bad, but usually after years of service. When I can’t get one to start, I try squirting some starting fluid into the carb air intake. It will usually run a couple of seconds on that charge and sometimes that’s all it takes to get things cleared out.

Some of these engines have oil level sensors and cut off the ignition if the level gets too low. But, in your case you said you had spark. 

Are you certain the choke is working properly? I had a linkage come loose on one once.

Skip

[carusoam]

What was the OAT?

If really cold... expect to use more fuel to prime than usual...

Once started with the choke full on... slowly adjust the choke towards being off...

It will take being warmed before the choke can be completely turned off may take a minute or two....

This came from our last operation of the leaf blower, and first operation of the snow blower for the year...

Leaf blowers used on snow are funny... they make great snow blowers... literally.   It’s also a nice way to run the tank out.

 

PP thoughts only, not a small motor mechanic...

Best regards,

-a-

[Sandman993]

14 minutes ago, carusoam said:

What was the OAT?

If really cold... expect to use more fuel to prime than usual...

Once started with the choke full on... slowly adjust the choke towards being off...

It will take being warmed before the choke can be completely turned off may take a minute or two....

This came from our last operation of the leaf blower, and first operation of the snow blower for the year...

Leaf blowers used on snow are funny... they make great snow blowers... literally.   It’s also a nice way to run the tank out.

 

PP thoughts only, not a small motor mechanic...

Best regards,

-a-

It was in the low 60’s... I’ve only seen pictures of snow. Just kidding, it snowed here briefly about 5 yrs ago.

I choked the puddin out of this thing. That’s why I pulled the spark plug... figured I drowned it. Seems to have good compression too. It probably doesn’t have 3hrs ttsn.

I’ll get into it and come back with a report. Was certain someone else would have had this encounter. 
 

I was going to take notes and write as fast as I can.

[carusoam]

There were a bunch of people buying portable generators a while back...

There has got to be some experience to be shared...

See if anything stands out from this list...

https://mooneyspace.com/search/?q=Portable generator&updated_after=any&sortby=relevancy&search_and_or=and

See who we can invite to the discussion...

Best regards,

-a-

[Hank]

7 minutes ago, Sandman993 said:

It was in the low 60’s... I’ve only seen pictures of snow. Just kidding, it snowed here briefly about 5 yrs ago.

I choked the puddin out of this thing. That’s why I pulled the spark plug... figured I drowned it. Seems to have good compression too. It probably doesn’t have 3hrs ttsn.

I’ll get into it and come back with a report. Was certain someone else would have had this encounter. 
 

I was going to take notes and write as fast as I can.

Hmmm . . . How long ago did you fill the tank? My generator wouldn't start last fall--drained and refilled, no problemo.

[AIREMATT]

44 minutes ago, Sandman993 said:

I choked the puddin out of this thing. That’s why I pulled the spark plug... figured I drowned it. Seems to have good compression too. It probably doesn’t have 3hrs ttsn.

Have you pulled the plug and squirted a little gas into the cylinder to see if it fires? That usually will pull anything through and get it going if it fires. Might have to do it a couple times before it runs steady but it should fire up until the squirt of gas burns up at the very least.

[Sandman993]

32 minutes ago, AIREMATT said:

Have you pulled the plug and squirted a little gas into the cylinder to see if it fires? That usually will pull anything through and get it going if it fires. Might have to do it a couple times before it runs steady but it should fire up until the squirt of gas burns up at the very least.

Sound like something to try before I pull the carb apart.

dunno what draining the gas would do... it’s probably 70/30 av gas

[PeteMc]

Okay....  So what does leaded fuel do to a fuel system that's not designed for leaded fuel?  Are there any additives common to leaded fuels that can gum up the system?  And does the generator really have a Carb. or is it injected.  Some small engines these days are injected.

 

[PT20J]

2 hours ago, PeteMc said:

Okay....  So what does leaded fuel do to a fuel system that's not designed for leaded fuel?  Are there any additives common to leaded fuels that can gum up the system?  And does the generator really have a Carb. or is it injected.  Some small engines these days are injected.

 

Engine/carbs don’t care about lead — same as your airplane. Autos engines will run fine on leaded gas. The lead kills the catalytic converter, not the engine. Lots of us run avgas in tug engines.

[carusoam]

Check the owners manual...

They may have one online...

There may be a list of common issues...

Including things like the vent got closed/blocked... and air can’t get in the tank...

For lead to be a problem, it would need to evaporate in the same place, a lot, over time...  not just one tank drying up...

The nice thing about 100LL... it is very stable, and doesn’t evaporate very quickly... under most conditions...

 

-a-

[Sandman993]

9 hours ago, PeteMc said:

Okay....  So what does leaded fuel do to a fuel system that's not designed for leaded fuel?  Are there any additives common to leaded fuels that can gum up the system?  And does the generator really have a Carb. or is it injected.  Some small engines these days are injected.

 

I’m told the av gas dries out the gaskets. It’s not the lead... 

there are old pilots round here that say av gas will eventually screw up the carb gaskets and or o rings. They even older than I am.

I did recently rebuild part of my tug carb... it developed  a mystery leak and yes, I use av gas.

[N201MKTurbo]

So, avgas is an almost pure substance (alkylate) while Mogas is a witches brew of stuff. If you let avgas sit it just looses volume over time due to evaporation. Mogas evaporates unequally and changes composition over time. That is why car gas goes bad if you let it sit, not so much with avgas. It would be best if you ran your little generators on avgas or drained them after use. And refilled the supply can every season.

Edited January 24, 2021 by N201MKTurbo

[PeteMc]

Not the lead I was asking about....   Are there any ADDITIVES in 100LL that may be an issue? 

I doubt there are.  But I really don't know and was curious if there is something in 100LL that a little engine designed for modern auto gas wouldn't like.  Especially after some storage time.

 

[carusoam]

The LL and blue dye... when allowed to dry in the same place like in the carburetor, or in the tubes after the carburetor...

Has a tendency to leave behind a thick layer of blue goo...

The same stuff that appears at a fuel leak... often appears brown after a while...

Ever clean out the intake tubes on an O360?

Lots of fuel needs to evaporate for any amount of goo to appear...

PP thoughts only...

Best regards,