. Anyway works great. Takes about 3 hrs to pre-heat. I just set a timer to turn the unit on, and when I arrive it's ready to go. I should say that my plane is in a T-Hangar...that's all that's available. Might take less time in a fully enclosed hangar.Preheating
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Hey George- I was going to let you know after reading your post on your pre-heater, I went to Home Depot and bought the components and rigged up a similar system. Just in time too, because Christmas week it got down into the 'teens here in Louisiana...that's bad for us. The governor almost declared a state of emergency . Anyway works great. Takes about 3 hrs to pre-heat. I just set a timer to turn the unit on, and when I arrive it's ready to go. I should say that my plane is in a T-Hangar...that's all that's available. Might take less time in a fully enclosed hangar.
. Anyway works great. Takes about 3 hrs to pre-heat. I just set a timer to turn the unit on, and when I arrive it's ready to go. I should say that my plane is in a T-Hangar...that's all that's available. Might take less time in a fully enclosed hangar.Jim Brown
N9753A
'49 C170A
N9753A
'49 C170A
Glad it works well for you. I usually begin mine the night before in order to thoroughly get the oil and internal engine parts warmed. Most pre-heaters, given insuficient time, will heat only the locallized area and fool one into believeing the thing is warmed when in actuality most internal parts are pretty chilled. It taikes a long time to warm a crankshaft/cam and all the oil in the sump. Dipstick heaters will cook the oil surrounding the dipstick, but allow the oil in the farthest passages to remain congealed, which makes for blockage during the critical start-up phase. Cylinder-head heaters do the same thing. (I'm not a fan of the Tanis system for the following reason: Cylinders, by deliberate design, dissipate heat rapidly/efficiently to atmosphere thru their cooling fins, therefore the Tanis Cylinder-head heater-probe is the most inefficient system available, in my opinion. Cylinder-base heaters are probably better in that they probably transfer more heat to the crankcase area, but still that's pretty locallized. Hot cylinder walls simply encourage whatever oil film remaining from the previous engine run to abandon the cylinders and drain down into the sump to join all that other (normally unheated) oil.
The oil sump heating pads are not my favorite either, because in hot weather they serve to insulate the sump from dissipating heat into the air flow. (After all, they ARE a glued-on blanket.)
The best system, in my view, is a system that heats the entire engine environment for sufficient time to make that engine believe it's in a temperate climate. That way the entire system, cylinders, crankcase, crank/cam, oil sump/contents, and accessories (including that carburetor which is critical for arctic starts without excessive priming) are all thoroughly warmed and ready for immediate service upon startup. (The excessive priming is legendary in C145/O30's, and is accompanied by a very real fire hazard. Keep a fire extinguisher handy in the hands of an observer outside the aircraft. By the time the pilot is aware of a cowling/carb fire, considerable damage/loss of the aircraft can occur. (Remember to instruct him to discharge the extinguisher up the cowl lower exit if the fire is external to the carb due to dripping fuel. Discharging it into the inlets is rarely useful.)
The drawback to my system is it's bulkiness and time requirement. But if the time requirement is a problem for an operator...then the other systems are even more limited. IMHO
The oil sump heating pads are not my favorite either, because in hot weather they serve to insulate the sump from dissipating heat into the air flow. (After all, they ARE a glued-on blanket.)
The best system, in my view, is a system that heats the entire engine environment for sufficient time to make that engine believe it's in a temperate climate. That way the entire system, cylinders, crankcase, crank/cam, oil sump/contents, and accessories (including that carburetor which is critical for arctic starts without excessive priming) are all thoroughly warmed and ready for immediate service upon startup. (The excessive priming is legendary in C145/O30's, and is accompanied by a very real fire hazard. Keep a fire extinguisher handy in the hands of an observer outside the aircraft. By the time the pilot is aware of a cowling/carb fire, considerable damage/loss of the aircraft can occur. (Remember to instruct him to discharge the extinguisher up the cowl lower exit if the fire is external to the carb due to dripping fuel. Discharging it into the inlets is rarely useful.)
The drawback to my system is it's bulkiness and time requirement. But if the time requirement is a problem for an operator...then the other systems are even more limited. IMHO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
George,
I agree that the most important thing is to ensure that the entire engine is more or less evenly heated. The best way to do this, however, regardless of the heat source, is to apply an insulated engine cover while heating.
The Tanis system does NOT just use cylinder probes for its heat source. It also incorporates an oil sump heat pad and two narrow heat pads that attach to the top of the engine case.
Sorry, but there is no way that the (rather small) heat pad is going to have any significant effect on cooling the oil during hot weather.
I prefer the Reiff pre heat system, for an installed system, to the Tanis, though I've used the Tanis as well for years, and they work fine. I prefer the Reiff for two reasons:
1) Its cheaper than the Tanis
2) It uses cylinder base bands instead of occupying the cylinder's CHT probe holes for heat to the cylinders. The Tanis system basically precludes the use of multi probe CHT's, which I am a fan of. I know, George, if Cessna had thought it was necessary for a pilot to know the temperature of every cylinder, they'd have installed it at the factory.
The simplest heat source, for occasional use is to get hold of one of the small ceramic fan forced heaters, stick it inside your cowl, and cover the works with an old sleeping bag. At 15 degrees or so, it'll be ready to go in an hour to an hour and a half, and its safe.
Mike Vivion
I agree that the most important thing is to ensure that the entire engine is more or less evenly heated. The best way to do this, however, regardless of the heat source, is to apply an insulated engine cover while heating.
The Tanis system does NOT just use cylinder probes for its heat source. It also incorporates an oil sump heat pad and two narrow heat pads that attach to the top of the engine case.
Sorry, but there is no way that the (rather small) heat pad is going to have any significant effect on cooling the oil during hot weather.
I prefer the Reiff pre heat system, for an installed system, to the Tanis, though I've used the Tanis as well for years, and they work fine. I prefer the Reiff for two reasons:
1) Its cheaper than the Tanis
2) It uses cylinder base bands instead of occupying the cylinder's CHT probe holes for heat to the cylinders. The Tanis system basically precludes the use of multi probe CHT's, which I am a fan of. I know, George, if Cessna had thought it was necessary for a pilot to know the temperature of every cylinder, they'd have installed it at the factory.
The simplest heat source, for occasional use is to get hold of one of the small ceramic fan forced heaters, stick it inside your cowl, and cover the works with an old sleeping bag. At 15 degrees or so, it'll be ready to go in an hour to an hour and a half, and its safe.
Mike Vivion
Knowing me as most of you do by now,....I'd caution against assuming you know what I think.mvivion wrote: I know, George, if Cessna had thought it was necessary for a pilot to know the temperature of every cylinder, they'd have installed it at the factory.
Mike Vivion
I do not concur.
In airplanes of this price-category, Cessna did not spend any more money that they felt absolutely necessary regarding auxillary systems. The FAA (CAA actually) did not require CHT intrumentation at all. (CHT instrumentation is only required by certification rules on aircraft with moveable cowl flaps.) Since the 170 has a fixed cowl flap no CHT gauge was required. It was offered as an option.
IN ANY CASE --- The C145/O300 engine does not have provisions for CHT probes, so consideration of that system is pointless for that engine. (Note: Some aftermarket cyls do have such provisions.)
(The only system available to our original engines is the spark-plug gasket type, and it can be appied to multiple cylinders without penalty (other than to the pocketbook.) If only one cylinder is sampled, the recommendation is to sample #2.)
The cylinder-base bands still have to deal with the fact that so much of their heat is dissipated because of the design of the cooling fins. On the other hand, application of hot air into the cowl will actually be facilitated by the cylinder fins, in my opinion, as they will help absorb the heat.
I guess this revolves around whether or not an installed system is better than a forced-air heat system, and I believe it is not.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
George wrote:
A picture of these cylinders at their website––
http://www.eci2fly.com/Tech_Ref/titan/2 ... atures.htm
––shows the threaded CHT Probe Boss.
Gordon Sandy
1948 Ragwing (with an 0-300 from a C170B with two overhauled TCM cylinders circa 1954, one TCM cylinder circa 1993, one ECI "Classic Cast" cylinder circa 1999, and two ECI "Titan" cylinders circa 2004)
Given my propensity to talk about ECI cylinders, it must sound like I'm a salesman for the company. I assure you, that is not the case. But, ECI's 0200/0300 Titan cylinders do have provisions for CHT probes.IN ANY CASE --- The C145/O300 engine does not have provisions for CHT probes, so consideration of that system is pointless for that engine.
A picture of these cylinders at their website––
http://www.eci2fly.com/Tech_Ref/titan/2 ... atures.htm
––shows the threaded CHT Probe Boss.
Gordon Sandy
1948 Ragwing (with an 0-300 from a C170B with two overhauled TCM cylinders circa 1954, one TCM cylinder circa 1993, one ECI "Classic Cast" cylinder circa 1999, and two ECI "Titan" cylinders circa 2004)
In the olden days when I was in Alaska, we knights of the air (when we weren't setting young female hearts aflutter) used to pre heat with an engine tent and a gasoline fired plumbers fire pot. On my Stinson L-5, I drained the oil into a three gallon can with an asbestos shield on the bottom. The can was placed on top of the fire pot and heated as the engine was warmed. The hot oil was poured into the engine just before starting.
My uncle,Sam, to whom I was in indentured servitude, had about two hundred Herman Nelson heaters in my squadron but I was never able to figure how to get one out the main gate on the base if I managed to liberate it from government servitude. I would have been king of Weeks Field, the Fairbanks Municipal Airport.
My uncle,Sam, to whom I was in indentured servitude, had about two hundred Herman Nelson heaters in my squadron but I was never able to figure how to get one out the main gate on the base if I managed to liberate it from government servitude. I would have been king of Weeks Field, the Fairbanks Municipal Airport.
BL
George,
I think before you pontificate on the best way to preheat an engine, you should perhaps move to Fairbanks for a few winters
Remember, I said that an engine heater of any kind will only accomplish what you are assuring is the best way to heat an engine (ie: a normalized engine heat condition) if the engine is contained in an insulated blanket.
Note that even if you heat the case, that heat then dissipates via the cylinders, albeit slower.
On the other hand, if you cover the engine with a blanket, anywhere the heat is applied radiates into the contained space within the cowling cover, and evenly heats the WHOLE ENGINE, which is the point.
You might note that cooling cylinders work both ways, incidentally, which is why folks worry so much about shock cooling. So, cylinders can not only radiate heat to the atmosphere, but absorb heat from it as well.
Again, I can tell you that at the temperatures most folks operate, a simple ceramic fan heater will work fine, with an engine blanket to normalize the heat throughout the engine.
If you live in actually cold country, you really need to buy one of the installed type units, if you have access to electricity. They work well, they have no moving parts, and they will last well past the TBO of the engine.
If you don't have electricity, there are many other ways to pre-heat an engine, none of them pretty,
Mike Vivion
I think before you pontificate on the best way to preheat an engine, you should perhaps move to Fairbanks for a few winters
Remember, I said that an engine heater of any kind will only accomplish what you are assuring is the best way to heat an engine (ie: a normalized engine heat condition) if the engine is contained in an insulated blanket.
Note that even if you heat the case, that heat then dissipates via the cylinders, albeit slower.
On the other hand, if you cover the engine with a blanket, anywhere the heat is applied radiates into the contained space within the cowling cover, and evenly heats the WHOLE ENGINE, which is the point.
You might note that cooling cylinders work both ways, incidentally, which is why folks worry so much about shock cooling. So, cylinders can not only radiate heat to the atmosphere, but absorb heat from it as well.
Again, I can tell you that at the temperatures most folks operate, a simple ceramic fan heater will work fine, with an engine blanket to normalize the heat throughout the engine.
If you live in actually cold country, you really need to buy one of the installed type units, if you have access to electricity. They work well, they have no moving parts, and they will last well past the TBO of the engine.
If you don't have electricity, there are many other ways to pre-heat an engine, none of them pretty,
Mike Vivion
What is it about volunteerism that attracts criticism? Try to help, and you set yourself up as a target.
I do not appreciate your choice of words, Mike. Smiley faces do not change your intent.
As a volunteer at TIC170A I am asked to offer the best advice I can, and I attempt to offer complete expanations of my opinions in an effort to provide an underlying understanding of the issue. It is not "pontification" to explain in detail to those who seek the info. You weren't forced to read it, and you don't have to use it.
You seem to think I disagree about the use of a blanket. I have no idea why you believe that, as I said nothing to detract from that. In other message postings I have made the same suggestion if you wish to research it. I've also recommended propellor covers because a prop is an excellent heat-sink to steal heat away from an engine.
Just because you happen to be in AK does not mean you have a monopoly on cold. There are other places in the world that know something about it. A 35 year career flying over much of that world, including Canada, Greenland, Iceland, and northern Europe has given me a modicum of exposure to methods to preheat engines. You don't have to use my recommendations, and neither do you have to defend the methods you use, Mike. Just because a different method than your own is suggested/described doesn't mean you're being accused of stupidity. It 's not necessary to demean the efforts of others.
Your observation: "...cylinders can not only radiate heat to the atmosphere, but absorb heat from it as well.".... is exactly the reason I previously suggested that a forced hot-air system is superior to all others, including installed systems. A forced air system heats not just the cylinders or sump, but heats the entire assembly including accessories.
"....If you live in actually cold country, you really need to buy one of the installed type units..."
Just because someone "lives" in cold country doesn't make the superior forced air system less so. I only emphasized it's superiority, in my opinion. (True, it may not be as convenient. We all like convenient, simple solutions, and an installed system is simpler to operate because it requires less set-up. One has to define "best". Is the "best" system the easiest? Or the most effective? For some it may be whatever it takes to get them to use it. As for myself, I'd rather not fool myself into believing I'm doing my engine some good by preheating only a few small spots on the engine. I'd rather warm up everything under the hood.)
I do not appreciate your choice of words, Mike. Smiley faces do not change your intent.
As a volunteer at TIC170A I am asked to offer the best advice I can, and I attempt to offer complete expanations of my opinions in an effort to provide an underlying understanding of the issue. It is not "pontification" to explain in detail to those who seek the info. You weren't forced to read it, and you don't have to use it.
You seem to think I disagree about the use of a blanket. I have no idea why you believe that, as I said nothing to detract from that. In other message postings I have made the same suggestion if you wish to research it. I've also recommended propellor covers because a prop is an excellent heat-sink to steal heat away from an engine.
Just because you happen to be in AK does not mean you have a monopoly on cold. There are other places in the world that know something about it. A 35 year career flying over much of that world, including Canada, Greenland, Iceland, and northern Europe has given me a modicum of exposure to methods to preheat engines. You don't have to use my recommendations, and neither do you have to defend the methods you use, Mike. Just because a different method than your own is suggested/described doesn't mean you're being accused of stupidity. It 's not necessary to demean the efforts of others.
Your observation: "...cylinders can not only radiate heat to the atmosphere, but absorb heat from it as well.".... is exactly the reason I previously suggested that a forced hot-air system is superior to all others, including installed systems. A forced air system heats not just the cylinders or sump, but heats the entire assembly including accessories.
"....If you live in actually cold country, you really need to buy one of the installed type units..."
Just because someone "lives" in cold country doesn't make the superior forced air system less so. I only emphasized it's superiority, in my opinion. (True, it may not be as convenient. We all like convenient, simple solutions, and an installed system is simpler to operate because it requires less set-up. One has to define "best". Is the "best" system the easiest? Or the most effective? For some it may be whatever it takes to get them to use it. As for myself, I'd rather not fool myself into believing I'm doing my engine some good by preheating only a few small spots on the engine. I'd rather warm up everything under the hood.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
-
Harold Holiman
- Posts: 579
- Joined: Tue Apr 23, 2002 1:54 pm
Although it probably wouldn't work for Alaska type cold, mine works good for me and is very inexpensive. I use a small ceramic heater. I made a trough type duct that one end sits on the floor and the other end fits in my cowl flaps. I sit the heater on the floor right against the bottom of the duct which goes up at about a 45 degree angle. I have a old quilt I put over the cowling. If I plan to fly when it is cold, I turn the heater on the day or afternoon before and the next morning all is nice and warm.
Harold
N92CP
Harold
N92CP
-
Jr.CubBuilder
- Posts: 517
- Joined: Thu Aug 12, 2004 10:33 pm
It may seem so...but I don't appreciate someone that doesn't know me or my background try to imply that because I don't live in Fairbanks that advice based on well-founded and widely accepted methods on preheat is "pontificating". Got a different method you like? Fine. Tell us about it. But keep personalized criticisms out of the picture.
Living in AK does not make one an "expert" anymore than being from Texas makes one expert on global warming. Don't think an engine pre-heater pad glued to your oil sump degrades it's ability to dissipate heat? Consider that the only way your original engine had to get rid of heat from the oil is the sump's ability to shed it to atmosphere. That little opening below the prop provides cool air directly to the sump in an effort to get rid of that heat. Blank off several inches of sump surface and the oil will simply not be able to get rid of heat as effectively. It's that simple and this engine already has a reputation regarding that matter.
Living in AK does not make one an "expert" anymore than being from Texas makes one expert on global warming. Don't think an engine pre-heater pad glued to your oil sump degrades it's ability to dissipate heat? Consider that the only way your original engine had to get rid of heat from the oil is the sump's ability to shed it to atmosphere. That little opening below the prop provides cool air directly to the sump in an effort to get rid of that heat. Blank off several inches of sump surface and the oil will simply not be able to get rid of heat as effectively. It's that simple and this engine already has a reputation regarding that matter.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.