What is this thing and does it create vacuum?
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What is this thing and does it create vacuum?
 
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This post was updated on .
It all started by troubleshooting the AC/Heater/Temperature controls. The truck is defaulting to defrost. Following tips from the forums I traced the vacuum lines from the control knobs in the cab to the engine bay. Half the lines are missing (I think) and there is no distribution panel on the firewall in the engine bay.
After doing some more research I believed the problem to be a disconnected air pump. I bought a belt, connected the air pump to the alternator, turned the truck over and expected to pull vacuum. Nothing. Now I'm scratching my head and seeking advice. Is this an air pump? Does the air pump create vacuum for the heater/ac/temp control knobs in the cab? 
1984 F250 4x4
Stock 460 dual tanks Edelbrock 1406 Automatic transmission "hot fuel option" Father/Son project |
Re: What is this thing and does it create vacuum?
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One more thing. This is the vacuum hose diagram from this 1984 F250 w/a 460 and AC. All the vacuum lines are missing and I'm having a hard reading/understanding this diagram. Any help is appreciated.
1984 F250 4x4
Stock 460 dual tanks Edelbrock 1406 Automatic transmission "hot fuel option" Father/Son project |
Re: What is this think and does it create vacuum?
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In reply to this post by '84-460-Project
Air pump is for emissions, vacuum is sourced off the intake manifold behind the carburetor. There should be a line from there to a small vacuum manifold on the firewall near the underhood HVAC case. The vacuum line may tee to a small tank after going through a check valve.
This may help, I had already updated my HVAC system to a 1996 so the vacuum tank on yours will be a metal can on the fender. 
Bill AKA "LOBO" Profile
"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413 |
Re: What is this think and does it create vacuum?
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Re: What is this thing and does it create vacuum?
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Re: What is this thing and does it create vacuum?
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Jim. it could be this one:
 This is the one from the 1990 parts donor truck. It's even simpler now, no need for the air pump as it's sole function was to feed the center of the catalytic converter, also no MAP sensor with MAF.
Bill AKA "LOBO" Profile
"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413 |
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Re: What is this thing and does it create vacuum?
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This post was updated on .
Great information. Thanks for posting the EVTM.
It appears I missing (2) critical pieces: A (5) port manifold fitting and a vacuum distribution block. I have a (3) port manifold fitting on the back of the intake (picture) that feeds the transmission, brake booster and speed servo.  I have a (2) port vacuum tree and (3) port vacuum tree both coming off of the coolant line/thermostat housing (picture) at the front of the engine. None of these are creating vacuum.  I assume i need to go find a (5) port manifold fitting and a (3) port vacuum distribution block?
1984 F250 4x4
Stock 460 dual tanks Edelbrock 1406 Automatic transmission "hot fuel option" Father/Son project |
Re: What is this thing and does it create vacuum?
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If the only thing w/o manifold vacuum is the HVAC system just plug it into the manifold vacuum port on the front driver's side of the carb, as shown in Figure 1 in the Edelbrock installation manual. But, as was said, you do need the check valve/tee and vacuum reservoir shown in the Vacuum Systems pics or your HVAC system will default to Defrost when the vacuum goes away with heavy throttle.
As for the ones on the thermostat housing, they are temperature controlled and were part of a complex system to provide vacuum for various emissions systems at specific temps. Since you have an aftermarket carb and no belt on the AIR pump I'm guessing you aren't worried about emissions. In that case I would remove those valves and plug the holes with pipe fittings. Then I'd set my vacuum advance up with ported vacuum from the timed port on the Edelbrock carb, which is the port on the front passenger's side. And if you aren't using the thermactor system we can talk about how to remove it. 
Gary, AKA "Gary fellow": Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
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Re: What is this thing and does it create vacuum?
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Re: What is this thing and does it create vacuum?
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Re: What is this thing and does it create vacuum?
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Re: What is this thing and does it create vacuum?
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In reply to this post by '84-460-Project
I've not put the HVAC hose to the carb, but it will work. The manifold vacuum off the manifold is the same as the manifold vacuum port on the carb. In fact, if you pull the carb and trace that port you'll see it makes a 90 and goes down into the manifold. But, you have ported/timed and manifold vacuum backwards. Manifold vacuum is there all the time, but timed or ported vacuum is not there at idle and comes in as you open the throttle slightly. I like timed vacuum for the vacuum advance. The vacuum diagrams Jim referred to are here: Documentation/Underhood/Vacuum Systems/Vacuum Diagrams/460 V8. Jim - The EVTM doesn't differentiate by engine. The vacuum diagram is shown below, and that's the same setup Big Blue has. Perhaps the '87 and later ones have the vacuum tank and check valve built into the system in the cab? 
Gary, AKA "Gary fellow": Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
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Re: What is this thing and does it create vacuum?
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In reply to this post by '84-460-Project
Here is mine for emissions:
 On mine, white is the EGR valve ported vacuum signal Green is the EGR valve signal from the 4 port thermal vacuum valve on the thermostat housing It also goes to two of the four purge control valves and is run through a delay valve Yellow is a ported signal for one of the purge valves Red is direct manifold vacuum and goes to the vacuum bowl vent valves, the air filter heat control and WOT air inlet, one purge valve, the two air pump diverter valves and the bottom port on the 4 port valve, through a restrictor to the upper port on the 3 port thermal vacuum valve. Black is from the 2nd port on the 4 port valve, and there is a big (3/8") hode to a front manifold port for the purge system. the smaller black lines run to the air pump diverter valves through a vacuum control valve. Here is what the vacuum harness looked like off the engine, repaired section in the middle of the bundle is where the exhaust crossover melted it. 
Bill AKA "LOBO" Profile
"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413 |
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This post was updated on .
Now he does, I believe he had a metal one originally, looked like a large soup can on the right inner fender. Since replaced by the plastic one on the side of the evaporator housing. I went through my emission labels, there were only 3 systems in 1984 and two of them match what his looks like. I reduced them both to forum size and can post them or you should have them 3-97J-R10 and 3-97J-R11, the other one 4-98S-R0 is much more complex and may have been late 84 or CA spec 84. Since his has a Carter rather than Holley carb, it can probably be used as it doesn't seem to have the bowl vent valves.
Here, these two may help, these are 1983-84 460 diagrams:   These show the components on the engine.
Bill AKA "LOBO" Profile
"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413 |
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In reply to this post by Gary Lewis
No Gary. My truck definitely never had any vacuum reservoir or check valve. I will take pics of what is left in the AM when the rain stops.
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake. Too much other stuff to mention. |
