ACV question - in middle of Duraspark conversion

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ACV question - in middle of Duraspark conversion

BigDav782
Hi all,

I'm almost complete with the Duraspark conversion, but have a couple of lingering questions:

1.  There are two small vacuum lines from the intake manifold, to solenoid valves (that are coming out because they are powered by the EEC), which then terminate at the air control valve.  What do I do with them - hook them up directly to a normal source of vacuum, or eliminate them and cap them at this air control valve?

2.  Related to above...what the heck does an air control valve do?

Thanks!
Dave
'85 F150, I6, 4wd, 3 speed automatic
Hopkins, MN (Twin Cities)
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Re: ACV question - in middle of Duraspark conversion

Gary Lewis
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Dave - The diverter valve, aka air control valve, determines where the air from the AIR/smog pump goes.  If I remember correctly, the 300 six has a little manifold connected to the exhaust so the air can be injected there as well as into the exhaust upstream of the catalytic converter.  And the valve determines when and where it goes.

If you are eliminating the pump then you can eliminate the little manifold and the hoses to it and to the exhaust.  But you'll have to plug where the manifold was if you pull it, or just leave it and crimp over the tubing going into it.  Ditto the one going to the exhaust.

And, as background, the Air Injection Reaction (AIR/smog) pump gives extra air to the exhaust stream coming out of the engine so any un-burned hydrocarbons will burn.  And it gives extra air to the catalytic converter to help it do its job.
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
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: ACV question - in middle of Duraspark conversion

1986F150Six
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Gary Lewis wrote
And, as background, the Air Injection Reaction (AIR/smog) pump gives extra air to the exhaust stream coming out of the engine so any un-burned hydrocarbons will burn.  And it gives extra air to the catalytic converter to help it do its job.

I have wondered about this as my air pump is gone, the hoses blocked. With 213K miles, the truck still has the original catalytic converters. I wonder what condition the converters are in? I remind myself, though, that the engine runs quite well and returns decent fuel mileage.
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Re: ACV question - in middle of Duraspark conversion

Gary Lewis
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You'll know when the cat is plugged.  There's a college student at church whose 90's T-Bird started running very, VERY poorly.  Like, it wouldn't get up to highway speed.  They took it to a shop who pulled the exhaust pipe out of the cat to prove a theory, and sure enough it ran great, albeit somewhat loudly.

Back in the 80's, if I remember correctly, Ford used a honeycomb cat element and GM used pellets.  The honeycomb was known to either get so hot it would melt and plug or gradually quit working and plug from the un-burned soot.  But GM didn't have that problem.
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
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: ACV question - in middle of Duraspark conversion

BigDav782
Is there a way to keep the smog pump operating after the Duraspark conversion?  Or is deleting it a required step in the process?  
'85 F150, I6, 4wd, 3 speed automatic
Hopkins, MN (Twin Cities)
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Re: ACV question - in middle of Duraspark conversion

Gary Lewis
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Yes, it can be kept operating.  But it isn't easy.  You have to find a truck with a non-computerized control system for the smog pump and move that over.  I don't know which of the 300's had that, but the 351HO and the 460's had no computer but did have a smog pump.  And they had a DS-II ignition.
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
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: ACV question - in middle of Duraspark conversion

85lebaront2
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Two items, look at the computer spreadsheet, some 300s had an MCU but prior to 1984 they did not use a feedback carburetor. The air pump can be kept, but you will need a diverter valve to keep from backfiring in the exhaust. Many older vehicles used air pumps without computers, the diverter valve usually just dumped the air back to the air filter housing or just dumped to atmosphere.

The Ford style catalytic converters are now the norm, the gravel bed that everyone else used might not melt or break, but it had horrific back pressure even new, and required the strata be changed periodically.
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: ACV question - in middle of Duraspark conversion

ArdWrknTrk
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In reply to this post by Gary Lewis
Gary,
I think you have both my and Bill's vacuum routing diagrams.

They should show TWO A.I.R pumps and how the dump valves are controlled.
They are routed back to the air cleaner housing.
The system is simple, the solenoid array on the I-6 can be jettisoned and still have the pump working.
 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.
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Re: ACV question - in middle of Duraspark conversion

Gary Lewis
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Jim - They are here: Documentation/Underhood/Vacuum Systems/460.  But to make it easier, here they are:




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
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: ACV question - in middle of Duraspark conversion

ArdWrknTrk
Administrator
Looks to me that the BPV gets straight up manifold vacuum.
 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.