1986F150Six Posted December 2, 2020 Share Posted December 2, 2020 This was something asked about (being in the PCV line) a few months back. I recall that discussion but have never seen one in the wild. Search for Mystery Components [10/22/18] Oct 22, 2018; 4:07pmRe: Mystery Components 85lebaront2 Administrator 3010 posts First item is an air valve, used on A/C equipt vehicles to admit extra air into the intake under high temperature conditions, it is thermally controlled by a bimetal spring. Second was your choke hot air tube, but most of these engines didn't use a hot air choke, it was electric heated by the 7 volt stator feed from the alternator. Bill Profile "Getting old is inevitable, growing up is optional" Darth Vader 1986 F-350 460 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 LARIAT 85Reply | Threaded | More Selected postOct 22, 2018; 5:28pmRe: Mystery Components LARIAT 85 373 posts This post was updated on Oct 22, 2018; 5:38pm. In reply to this post by baddog8it The first component is called a Hot Idle Compensator Valve (HICV on your emissions diagram.) When the engine is hot, the air/fuel mixture is richer than normal. The HICV opens slightly to let in a little bit of air into the intake and below the throttle valve to lean out the mixture at idle to compensate for the richer mixture. The second component looks like a broken choke tube. Most Fords of this era used a thermostatic choke with electric assist. If that plate is bolted to the intake manifold, a tube was originally inserted in it to operate the choke. One end serves as a fresh air tube that connects to the carburetor air horn, the other a hot air tube that screws onto the choke assembly. The choke works in lockstep with the coolant temperature. As the coolant heats up, the tube also heats up and begins to open the choke. Full operating temperature = fully opened choke. (Small block engines used a chamber on the passenger's side exhaust manifold and uses the temperature of the exhaust to accomplish the same thing.) You should also have a wire connecting the choke cap to the back of the alternator. That would be the electric assist. It only works above about 60 degrees to help the choke come off faster. If the thermostatic choke isn't hooked up properly, you will have cold start problems if it temperatures are less than 60 degrees. Lucille: 1985 Ford F150 XLT Lariat *Colors: Dark Canyon Red exterior, Canyon Red interior *Engine: 5.0, CompCams 31-230-3, "Thumper" E7 heads, Edelbrock Performer intake, Autolite 4100 carburetor, DuraSpark II ignition, Thorley Tri-Y headers, Flowmaster dual exhaust, H-pipe. *Drivetrain: AOD transmission, 3.55 gears, 2wd. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 2, 2020 Share Posted December 2, 2020 Search for Mystery Components [10/22/18] Oct 22, 2018; 4:07pmRe: Mystery Components 85lebaront2 Administrator 3010 posts First item is an air valve, used on A/C equipt vehicles to admit extra air into the intake under high temperature conditions, it is thermally controlled by a bimetal spring. Second was your choke hot air tube, but most of these engines didn't use a hot air choke, it was electric heated by the 7 volt stator feed from the alternator. Bill Profile "Getting old is inevitable, growing up is optional" Darth Vader 1986 F-350 460 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 LARIAT 85Reply | Threaded | More Selected postOct 22, 2018; 5:28pmRe: Mystery Components LARIAT 85 373 posts This post was updated on Oct 22, 2018; 5:38pm. In reply to this post by baddog8it The first component is called a Hot Idle Compensator Valve (HICV on your emissions diagram.) When the engine is hot, the air/fuel mixture is richer than normal. The HICV opens slightly to let in a little bit of air into the intake and below the throttle valve to lean out the mixture at idle to compensate for the richer mixture. The second component looks like a broken choke tube. Most Fords of this era used a thermostatic choke with electric assist. If that plate is bolted to the intake manifold, a tube was originally inserted in it to operate the choke. One end serves as a fresh air tube that connects to the carburetor air horn, the other a hot air tube that screws onto the choke assembly. The choke works in lockstep with the coolant temperature. As the coolant heats up, the tube also heats up and begins to open the choke. Full operating temperature = fully opened choke. (Small block engines used a chamber on the passenger's side exhaust manifold and uses the temperature of the exhaust to accomplish the same thing.) You should also have a wire connecting the choke cap to the back of the alternator. That would be the electric assist. It only works above about 60 degrees to help the choke come off faster. If the thermostatic choke isn't hooked up properly, you will have cold start problems if it temperatures are less than 60 degrees. Lucille: 1985 Ford F150 XLT Lariat *Colors: Dark Canyon Red exterior, Canyon Red interior *Engine: 5.0, CompCams 31-230-3, "Thumper" E7 heads, Edelbrock Performer intake, Autolite 4100 carburetor, DuraSpark II ignition, Thorley Tri-Y headers, Flowmaster dual exhaust, H-pipe. *Drivetrain: AOD transmission, 3.55 gears, 2wd. Well sure.... October of 2018 was a few (26) months back. Thanks for digging that up, David! Link to comment Share on other sites More sharing options...
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