carburetor pre-heater

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Mar 5, 2009 | 05:34 PM

Jermafenser

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Joined: Jul 2001

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From: MD

carburetor pre-heater

I've been looking for a carburetor pre-heater without luck. My 78 F150 is missing it, causing it hard to start in cold weather. For anyone not familiar with it, it's a plate that hugs the passenger side exhaust manifold and it closes to a flange for a flexible metallic pre-heater hose to be installed between it and the air cleaner assembly.

Does anyone know of any sources? Tried rockauto.com, blueoval, and LMC without luck...

Mar 5, 2009 | 06:22 PM

Regg_65

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Joined: Feb 2008

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Not sure if it is a "pre heater" although at the local speed shop I found the heat riser for the carb. It bolts onto the manifold and a copper tube connects to the thermostat. Not sure if it is what you are asking for but if so I can find the website address or mailing address for you. Its in Carlisle Pa.

Mar 5, 2009 | 06:25 PM

fmc400

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Joined: Apr 2004

Posts: 10,386

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From: Austin, TX

The pre-heater \ hot-air intake system prevents the carburetor from icing up while it's running in cold weather, rather than helping it to start. When the motor is started cold, the air drawn in by the pre-heater isn't warm, so the air drawn in by the carburetor during the first couple minutes of running is cold anway, even with the pre-heater. If you are having cold-start problems, it's most likely choke related. The problem with running without a pre-heater is that once the engine is running, drawing cold air through tiny passages at high speed can ice the carburetor and cause the motor to run rough or stall. That's when you'd need to be looking into finding one. A junkyard is the only place you're going to find that plate. Any old pre-heater I've ever seen didn't work anyway because the vacuum diaphragm on the air cleaner snorkel doesn't work. A lot of people ditch them when they run headers or switch to an open-element air cleaner. You can still buy the hose though.