Ok. Someone explain this please

Found this pic on the internet of the air horn on a 1956 CJ5. What is the reasoning behind the mod on the airhorn and the extra hose. Just curious. Thanks

 

It certainly looks like a hot air modification but there would have to be another air filter on it the way its set up, We cant see the whole thing so I am going to guess that there is another air filter on the end of it..........I have never seen one but did overhear a conversation some years ago between two hot rodders that adding another filter woud increase performance by supplementing the oil bath, I personally dont agree with that concept for average use.

 

What's the opposite of "snorkel"?

 

Ok, I finally found out where I got the pic. I was checking eBay out for some odd and ends and came across this JEEP for sale. So I asked the owner. His response,

"the added hose is a very clever addition that a excellent mechanic put on for me that will keep the jeep running great even in below zero temperatures ! the hose is connected to a tube on the exhaust to feed warm air into the carburator so it will always run like a warm sunny day even when it is sub zero outside "

 

Added feature: dirt injection?

I'm sure it works well, but the air needs to be filtered. Later Jeeps with the TAC (thermostatic air cleaner) work similarly, but feed the warm air into the area outside the air cleaner. Good call, Lynn.

 

Good idea for winter, but I'd take it off for summer.

 

:iagree:R)

 

The air only needs filtered if there is a hole going from the tube to the carb inlet adapter thingy (don't laugh, I'm having a brain fart!) If no hole the heat from the manifold could still warm the air inside the tube and in turn warm the air going into the carb, or at least warm it enough to keep the venturi's from freezing. Not the most efficient, but could still work ok.

 

Sump Pump?

 

No laugh, that makes sense. I'm not sure if the volume is enough to make a difference though... might be. The hot air will rise and mix with the incoming air.

 

Drowning!

 

Its to keep you from trying to ford streams you shouldnt try in the firstplace.

 

I think Nickmil is spot on. That is exactly how most GM aircleaners are plumbed. Even my 240z has a similar setup. The air is not piped into the motor, just uses the heat to preheat the incoming air charge. Tiny carburetors are prone to icing even in the summer. Preheaters are supposed to help this and are considered emissions equipment, at least in Texas, for inspections.

 

I would think that in all but the most extreme conditions the water jacketed intake manifold on the F-Head would be sufficient to vaporize fuel droplets even though its all below the throttle plates, The carb body will no doubt be warmed some even with the carb base gasket in place. Hot air intake works and does have its place but I wonder how efficient it is on the early F-Heads that took intake air from under the hood and did not have the lean choke settings and in some cases lean low speed jetting of some of the more heavily emission control laden later models.

Just thinking out loud.........anyone out there have throttle plate icing problems with the F-Head or have experience with driveability issues due to extremely cold intake air.

I would really like to know whats on the other end of that hose, Cant really tell in the photos.

 

I can't speak for the F-head specifically in this case but I had a '74 Datsun pu with an L-18 4 cylinder that would ice up terribly in the right conditions. If it hit less than about 28 degrees outside and the hot air tube wasn't connected you'd go about a mile and that was it. I even had troubles on high humidity days when the outside temp was in the 70's that it would ice up. Just enough to cause problems if the hot air tube wasn't seated properly. The air inlet was under the hood on that truck, not directed from outside. Just an example of personal experience. It had coolant running through the intake also but still did it.

 

I can see where it ( heated air intake ) could be a practical modification in some cases. I have never experienced throttle plate icing to date, Even while living at higher & much colder elevations in the past. I will keep what you noted about the Datsun in memory.........You never know when Murphy's Law will prevail.

 

It actually wasn't the throttle plate icing up but the venturis. The fuel passages at the venturis would freeze up and not allow the fuel to come out so the engine would literally die from lack of fuel. That's why the old carbureted aircraft had carburetor heaters, to keep this from happening. I've only experienced it on a couple of vehicles, but that old Datsun was terrible about it. Had to be something about the design of that carb. It was the stock Hitachi carb which was a piece of nightmare anyway. My '78 with a Weber never had that issue, course it ran like crud until it warmed up anyway.... even with an operating choke. It had venturis that were more open and a better designed fuel inlet so that probably had a lot to do with the lack of icing.

 

My Solex will ice up in winter until the f-head warms up. You can see frost around the base of the carb, esp below the throttle plate. If I use the block heater the problem goes away because the head has heat in it. The Carter was less prone to it, although I didn't run it much before I swapped it out. 'Twas a leaker to say the least.

 

Hydro-lock your engine in shallow water where extraction is easier. Very practical, really!

Brother had an 86 CJ7 with 258 that would ice like crazy. After sitting for ten minutes it would allow you to drive another few miles before shutting down.

Hey, maybe that was another useful safety feature: the Jeep would strand you within walking distance of home when it was cold outside. In more survivable conditions it would strand us far from home.