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1978 f250 pickup with 390 engine... vacuum diagram?

Hi,

It looks like someone put vacuum lines on this engine incorrectly.

There are the two temp operated vacuum switches in the water flange on top of the engine. distributor vacuum advance (no retard) charcoal canister, EGR breather valve cover vacuum ports on intake (a bunch of them)

looking in the crappy chiltons manual, it shows the dist., with a line coming off it, going to a T, then to the carb and to one of the temp switches... this is definitely not the way it goes right now.

it goes dist-->temp switch. from temp switch it branches to two ports on the carb.

I would like a good description of the vacuum system.

right now the EGR isn't hooked up. the breathers on the valve covers aren't connected.

It will start, sounds pretty good. It dies about 2 seconds after keeping it revved a bit... it won't stay lit.

I'll take a picture with my digital camera and post it on a website, and repost here to see if anyone can help.

two barrel carb... pics are a thousand words so I'll stop typing and start getting snapshots

any assistance is appreciated!

Rich

Reply to
aiiadict
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snipped-for-privacy@gmail.com wrote in news:c40ef360-2168-4dc8-bb7c- snipped-for-privacy@s8g2000prg.googlegroups.com:

Are you sure its not a 77? that is the last year of the FE engs in the ford pkups. If it is truly a 78 then it probly is not a 390. KB

Reply to
Kevin

Not sure what year it is... I'll check next time I'm there... I'll take pics too

passenger side of engine block, in the exhaust manifold, is a plate with two metal pipes sticking out (vacuum)... the bottom of the plate is a coil of pipe that hangs into exhaust manifold, I'm assuming for preheating the air that gets vacuumed through it....

does anyone know where this is supposed to go? IE where do the other end of the hoses go?

Rich

Reply to
aiiadict

snipped-for-privacy@gmail.com wrote in news:e5b030e3-c097-4faf-8910-625c38383b7c@

62g2000hsn.googlegroups.com:

that is the heated air intake for the choke coil. one end is open the other goes into the choke housing on the carb. it is a insulated hard line. KB

Reply to
Kevin

how about drivers side valve cover breather? do you know where that goes?

Reply to
aiiadict

how about drivers side valve cover breather? do you know where that goes?

Is it the PCV your talking about? About 3/4 inch diameter. If so it is a large hose that goes to manifold vacuum usually on the carb.

It could just be a breather vent. Larger than the PCV and it will most likely go the air cleaner with a small filter inside the air cleaner. I recall a square hole, about 1 inch, in the cleaner where the nipple goes through then u attach the filter with a clip gizmo. Then the hose just slides over the nipple.

I guess if the truck wasn't built for California it could just have a vented cap on the valve cover vent. Just guessin here.

Reply to
ScottM

Yeah, PCV valve... on the drivers side valve cover. Has black

2 nipple connector, one of the nipples doesn't have a hole in it (factory didn't drill it out)... fairly large hose going nowhere right now...

manifold vacuum... do you know where exactly? I can hear a hell of a vacuum leak, and this must be it (According to the size of the hose... that is a big port on the carb or manifold which is sucking air right now)

Distributor: has vacuum advance.

it is connected to red vacuum valve on the water flange. Is this correct? then from that valve to two different ports on the carb...

I can't find a vacuum diagram ANYWHERE for this truck.. none of the manuals at the auto parts store, none of the archive sites, nowhere on the net, can't even find a torrent!

Rich

Reply to
aiiadict

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