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weber vacuum hookups on 77 ea71


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since this board never gets tired of weber swap questions....

 

1977 ea71, got the weber put on and would like to get all this vacuum stuff squared away. the car has a vacuum modulator seen in this pic:

000_0745.jpg

 

the modulator is right in front of the carb seat with four ports on the top (there is still a hose on the fourth port in this pic) and three ports on the passenger side. it's purpose is to simplify the hoses and while it does that, it also makes it harder to trace the vacuum system. i do have a diagram from the apropriate fsm, but it can't be trusted 100% because the modulator is different for MT, AT, high altitude, 4WD, etc...

it does seem to jive for the most part, though. let's refer to the ports on the top of the modulator as 1 through 4, left to right AS THEY APEAR IN THE PIC.

 

1 through 3 went straight up to the carb in obvious fashion:

 

 

000_0746.jpg

 

 

my weber has one port, it's on the front near the base. i had it hooked to the disty advance on my other car.

 

port #4 on the module doesn't worry me. it went to the side of the carb above the float bowl and it t'd off to the brake boost vac line. i capped it at the brake line.

 

 

port #2 t'd off to the canister. is this the purge? do i run this into the pcv junction? the only other line between the canaster and engine goes straight into the manifold. where does the canaster collect from?

 

what to do with the retard from the disty?

 

what about the line from the egr that goes into the vac mod?

 

and i have one vac port on the manifold capped where the costing bypass thing was, so i can use that if i need to.

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Just run a single vac line to the disty advance - leave the retard on the disty OPEN so it can breathe.

 

You should also have a port on the front of the Weber for the EGR - it may be blocked off with a brass scew. If not then don't worry about it - some older Weber's don't have the port drilled.

 

Plug everything else. The Weber has no facility for bowl vents or purge lines. That's why it's not DOT approved. Don't need any of that stuff anyhow.

 

GD

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The canistor can either be removed, or just fogotten about. Most people don't realize they are supposed to be replaced like every 50,000 miles or something and it probably isn't any good anymore anyway. It's a passive system so it won't cause any problems if just left disconnected.

 

If you don't have an EGR port on the Weber then you just leave it disconnected. The EGR won't open without vacuum supply from the carb so it's effectively disabled if you just don't hook it up.

 

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kay thanks, that about covers it. cept one more thing. the fuel-in line on a weber. you can run your fuel line in from the back or front? that sort of y shaped intake fitting is just a matter of where it is more convenient to run your fuel line? cause mine is on the front and i would rather run it into the back.

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kay thanks, that about covers it. cept one more thing. the fuel-in line on a weber. you can run your fuel line in from the back or front? that sort of y shaped intake fitting is just a matter of where it is more convenient to run your fuel line? cause mine is on the front and i would rather run it into the back.

 

Some you can, and some aren't drilled for it. If there's a brass bolt blocking off the other side then you can swap the inlet and the bolt.

 

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