carb ?'s

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May 30, 2004 | 11:37 AM

wckdclwn911

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carb ?'s

Ive gotta 74 f250, 360, factory 2bbl. I also work in a junk yard. Im thinking about swapping out my autolight carb for another, cause of anoying problems I cant pin down, and there seems to be a bunch where I work. My wuestion is that all the ones Ive found, even the same year, have this diaphram/vaccuum, thing on the back of the carb plate with vacuum lines, etc. My truck doesnt have this, the vacuum hole in the back of the carb goes to my pcv valve. Will I need to add the carb plate, and vacuum lines to the carb when I swap it out, is my truck supposed to have one (my problem maybe?), and what does it do??? Thanks for the input

May 30, 2004 | 01:35 PM

prcrboy

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Its the egr valve. Exhuast gas recirculation. Now, I'm not sure if you need it or not. Someone may have changed yours at one time. See if you can find the stamped number on the carb. If it has a ford number on it, it will begin with D for the 70's decade then a 4 for the 74 year. example- D2AF-AB is the carb on my 460 donor which is a 4bbl from a 72 LTD and it does have the egr. So yours was probally taken off when the restt of the emissions was removed.

May 30, 2004 | 02:58 PM

Torque1st

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If the EGR is removed the engine will often ping unless the distributor settings are changed.

May 31, 2004 | 01:32 AM

ashvalentine

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From: Addison,Texas

A 360 in an '74 F-250 should not have come with EGR from the factory. The way to check is to pull the carb and see if there's an exhaust hole in the intake manifold. (So, you would have three holes for EGR and not two.) If you've got the third hole you need the EGR plate or a phenolic spacer. If you don't, then an EGR+spacer is pretty much useless.

I'm assuming you are talking about the EGR and not the choke pull-off.

ash
['.']

May 31, 2004 | 08:22 AM

wckdclwn911

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I don't have the 3rd hole for the EGR valve, and i know that the motor's been rebuilt before I got it. So, can I take a carb with the EGR valve on it, and remove it to make it work on mine? My carb has a metal plate attached to one of the top plate screws that says DOTF B(1st line) coc3(2nd). There is a 74 f100 at work,360 2bbl but it does have the same looking carb plus the egr valve. Im wondering if mine was removed, and a hose run straight to the hole on the back of the carb, from the pcv??? OH THE CONFUSION!

May 31, 2004 | 10:48 AM

LxMan1

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From: Louisville,Ky.

D0TE means that it is off of a 1970 truck. Not original.

Jun 4, 2004 | 05:44 AM

ashvalentine

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From: Addison,Texas

You can leave out the plate. No third hole, no point. The PCV line runs to the back of the carb, unless you have have an EGR plate with the port in front. If the carb you're looking at doesn't have the baseport, but does have that, you'll have to pick another carb.

ash
['Aside from that you can run any old carb you want.']