What are your thoughts on using a carb heat pipe? Not needed, winter only, year round and why? Thanks, Steve
Mine will foul #1 plug without it. Changed plugs, gap, mixture, you name it, nothing worked but the heat pipe....
I guess it depends on the weather where you live, when you plan to use it. There are climates where you may get by most of the year without one, there are other climates where you can't run reliable without one. You can't go entirely wrong with one - but there's a big risk you'll eventually get fouled plugs or ice in your carb without one, so I'll vote for using it.
The cars run noticably better on hot days without a heat pipe. When it is near freezing or below the heat pipe makes the car run better. I put one on in cool / cold weather.
In Wisconsin, my heat tube stays on year round. If you are getting condensation on the intake manifold, you need it.
I live in southern California and use the heat tube year around. I have noticed that the intake manifold gets very cold even in hot weather, and I am sure that the heat tube helps the fuel vaporize. I don't notice any adverse reaction in hot weather. My plugs don't foul on any of my 3 T's. The fuel mixture is key to not fouling. too rich and you will foul, you will also get black smoke out of the exhaust if it is too rich.
I am using a Carb. air filter, but
I like to have a air filter AND a Hot air
pipe, is that possible????
Look up how a refrigerator or air conditioner works. Gas cools as it expands. Then look up a Carburetor. Gasoline expands into vapor. We run heaters all year round, even at 100 degrees on the 4th of July. The heater tubes on my thunderbolt engine were added because the intake was making ice cubes and it wouldn't run right.
The flatheads get them too:
You could run an air filter with a hot tube, but you would have to custom build it. Some later cars and pickups use a heater ahead of the filter. You don't want much resistance to the air flow in the input, because the T wasn't designed to us an air filter and it could cause it to run rich.
The vaporizer heats after the air intake, so it should be easiest to run a vaporizer setup with an air cleaner.
I'm putting this here because there is a clear photo above of the heater tubes and as this is related to carb heat (or lack of).
A number of people over the last year have talked to me about buying this engine, but no one put up the dough so it's still in my car. My answer of "how much" included a price and a condition that the intake and carb don't go with it.
I thought maybe some of you would like to know why I added that condition. I took some time recently and tried to correct the problem, and while it was apart I changed the cam timing and added a warford. I think I finally have the problem licked, so I posted the story on my website complete with photos.
And here is the original 2005 thread on this engine: http://www.mtfca.com/discus/messages/29/8632.html
I still use mine here in Australia, although most removed theirs many years ago and prefer not to use.
My inlet manifold gets to the point of ice cold if l dont run it ( not in summer though ), but dont modern cars utilise cold air induction as the prefered method of feeding the engine, as do large trucks !! Hmmmmmmmmmmm
I ran a filter for a some time and no trouble, just slow warming up. Last spring on the spring club tour, we were in some hilly country on a rainy day. My '23 started running like crap with a noticeable loss of power. I nursed her along to the next stop, but believe me, cars that wouldn't normally be able to get near me in hills, were passing me. When the rain slacked off, i got under the hood and the intake manifold was almost entirely frosted, white as snow. The air temp was not near freezing but needless to say, the humidity was near 100%. The air cleaner was a paper element rig I got from Snyder's. I like to drive on a dirt road once in a while, so I fret over the thought of pumping all that dust through the engine. All I can say is, if you are going on a trip and are running a filter, take that heat chimney with you. By the way, has anyone figured out where to get an element for that filter?
Yes, Michael Pawelek uses one of those filters and the replacement element can be had from Mr. Gasket. I can't find the thread so maybe Michael will chime in to help you.
Thank you, Seth. Happy New Year!
My pleasure. Happy New Year to you and yours as well!
If the O.D. of the element is 4" and height 2", it is Mr. Gasket part number 1489A.
When Tim shipped me my engine, he insisted I install the pre-heat tube. I live in sunny warm Florida, so naturally I didn't install it, thinking it was a cold weather thing.
When I finally did get around to it, I DID notice the difference.
I am currently using the paper filter and a "economy" period intake on my '19 touring so I can filter and pre-heat the air/fuel mixture at the same time! It works well so far and the Stromberg OF is something to smile about also! ....Michael Pawelek
PS- You can order the spare Mr. Gasket paper element from your local auto parts store.
Because aircleaners restrict airflow somewhat, it has been recommended to equalize the pressure in the float bowl with incoming air. I did that with the small aluminum tube you see here:
When I was a kid, I began flying lessons. I only had a few and had to drop out. Anyway the planes have carb. heat. As I remember, a little push-pull lever on the inst. panel, basically a manually operated heat riser assembly. I also remember reading in my manual that, ideal icing conditions were at 70 degrees temp. with 70 percent humidity due to the artificial atmosphere created inside the venturi of the carb. Maybe some of you pilots and scientists can explain it better.
I've always thought there probably are conditions when the engine doesn't need the heat stove, but it was designed for best performance overall.
"but dont modern cars utilise cold air induction as the prefered method of feeding the engine, as do large trucks"
Yes, you are correct. The difference is that those cars are fuel injected. The gasoline is injected into the engine at or on the intake valves (where it's already hot), diesel trucks do the same thing. Cars like a v8 mustang or 70's pickup truck have the intake wedged in between the heads, where it's warm.
That being said, the problem with our carburetor engines is that the gasoline is vaporized too far from the heat of the engine. When liquid is forced to expand into a gaseous state it gets colder, this is also how your air conditioner works. By warming the air going in, you keep the vaporized gas/air mixture from getting cold enough to turn back into a liquid. If it's too cold you can get droplets of raw gasoline in the intake, upsetting the air/fuel ratio of the mixture.
I agree Tim, and I know cold air is more dense than hot but that little Cessna 150 engine probably had more in common with design principles with a VW beetle than an inter-cooled turbocharged fuel injected engine.
Any carburater has some form of venturie in it so as to speed up the airflow and lower the pressure so as to suck the fuel out of the bowl. In doing so it cools rapidly as well as in the air conditioneer example mentioned above. This rapid cooling causes the humidity in the intake air to freeze on the inside of the carb and in the case of aircraft engines and Model t engines, in the intake itself. It actually forms ice on the inside of the carb/intake. My 1946 ercoupe with a c-75 continental engine has an intake filter housing that has a flapper in it to change the air intake from the filter to heated air taken from a muff wrapped around the exhaust stack. You add the carb heat as you throttle down to land, since they seem to ice up more under low or partial throttle.
Would coarse steel wool lightly oiled with KN air filter oil and wedged in the heat tube filter out the big chunks of dirt without restricting the airflow too much? I have seen big foam filters on dirt track gokarts but the heat might be too much and they might plug up too soon.
Fuel injected engines don't ice up because they have simple throttle valves, and no venturi.
Ice that forms on the wing of an airplane is so dangerous because it cripples the aerodynamics of the lifting surface. Rime ice, the grainy kind, is far worse than clear ice for polluting the aerodynamics.
Carb ice is rime ice that forms at the downwind end of the (aerodynamic) venturi, killing its ability to draw fuel into the airstream, and starving the engine of fuel.
That's a K&N on my engine, with Ford Model B ends.
I've had a dozen or so Stromberg OF's on my test engine in the last year or two and every one of them runs better with the Ford heat tube on the intake that without it. I don't have one of the original Stromberg "Hot Spot" setups but I'd sure like to try them. The manifold will get so cold without the intake heater that it will form frost on the outside of the manifold. I've never really paid that much attention to how much a standard NH or other Ford carb cools down the manifold but the OF's have a fairly small venturi and that must be what makes them frost up.
From what I've observed most up-draft carburetors have a certain degree of icing problems. I always assumed it had to do with the location being well below the hotter parts of the engine (cold manifold). I've seen several old antique tractors (updraft carb) with the lower part of manifold wrapped with everything from friction tape to inner-tube strips, as a home remedy. I doubt if this did more than hide the frost on the outside of the manifold. At least When you flood em real good or have a leaky needle & seat you don't wash the cylinder walls down or fill the crankcase up with gas. Worth the trade off to me.
From what I observe a Model T never has carb icing problems in typical Model T driving conditions. You know, warm summer day, surrounded by a dozen or more other Model T's, with a goal of eating ice cream always in the back of your mind. Also, the stock Model T carb is a side draft, not up draft.
Installing the carb heat stove on a hot day slows the car down. Taking it off makes the car go faster. This is an observation, not a theory.
On the other hand I do use carb heat stoves in the winter. Any of you guys ever actually dive your Model T's in the winter? Click here to see what it is like:
Happy New Year!
Royce, I misspoke, It is a side-draft carburetor I should have said up-draft manifold but with that it has the same advantages/disadvantages as an up-draft carb. I currently have a seasonal job and usually drive mine in cooler weather as time permits. Looking forward to the day when I'm able to drive mine and think about ice cream.