Vac throttle hold
September 22nd, 2015, 10:55 AM
#1
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Vac throttle hold
Anyone know of where I could find the vacuum throttle hold that keeps the engine running when you have the a/c on and are idling around town?
I remember pulling my old one off years ago when I never thought I would be restoring the car...
I remember pulling my old one off years ago when I never thought I would be restoring the car...
September 22nd, 2015, 04:51 PM
#4
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A dashpot does not hold the throttle open at a higher idle RPM with the A/C on. It simply prevents the throttle from slamming closed too quickly when you release it.
If the OP is really looking for a throttle kicker, there are two types. Most over the years have been solenoid actuated. These can work one of two ways, either the solenoid is normally retracted and then energized when the A/C is turned on, or it is energized whenever the ignition is in RUN and is retracted when you turn off the key to prevent dieseling (this was mainly used in the latter half of the 1970s). The VIN Y 307 cars DO use a vacuum actuated throttle kicker, however. The device was called an Idle Load Compensator and is the silver vacuum device at the front driver's side of the carb in this photo.
2012-06-01_21-53-52_825.jpg
Again, what year and engine? Or, are you trying to retrofit one to a non-original application?
If the OP is really looking for a throttle kicker, there are two types. Most over the years have been solenoid actuated. These can work one of two ways, either the solenoid is normally retracted and then energized when the A/C is turned on, or it is energized whenever the ignition is in RUN and is retracted when you turn off the key to prevent dieseling (this was mainly used in the latter half of the 1970s). The VIN Y 307 cars DO use a vacuum actuated throttle kicker, however. The device was called an Idle Load Compensator and is the silver vacuum device at the front driver's side of the carb in this photo.
2012-06-01_21-53-52_825.jpg
Again, what year and engine? Or, are you trying to retrofit one to a non-original application?
September 24th, 2015, 07:29 AM
#6
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hmm
Well the engine is out of a 72 toranado I believe due to the type of exhaust manifold that was on the old core. Using that quadrajet carb that have rebuilt.
Good to know the real name of the piece, dash pot. Next time I am up at the body shop will check to see what type of holes and where they are at on this particular carb will help in picking the dash pot out in pics.
Unless someone has one for this year of car. 72 Toranado, 455, 4 barrel
Good to know the real name of the piece, dash pot. Next time I am up at the body shop will check to see what type of holes and where they are at on this particular carb will help in picking the dash pot out in pics.
Unless someone has one for this year of car. 72 Toranado, 455, 4 barrel
September 24th, 2015, 07:30 AM
#7
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A dashpot does not hold the throttle open at a higher idle RPM with the A/C on. It simply prevents the throttle from slamming closed too quickly when you release it.
If the OP is really looking for a throttle kicker, there are two types. Most over the years have been solenoid actuated. These can work one of two ways, either the solenoid is normally retracted and then energized when the A/C is turned on, or it is energized whenever the ignition is in RUN and is retracted when you turn off the key to prevent dieseling (this was mainly used in the latter half of the 1970s). The VIN Y 307 cars DO use a vacuum actuated throttle kicker, however. The device was called an Idle Load Compensator and is the silver vacuum device at the front driver's side of the carb in this photo.
Again, what year and engine? Or, are you trying to retrofit one to a non-original application?
If the OP is really looking for a throttle kicker, there are two types. Most over the years have been solenoid actuated. These can work one of two ways, either the solenoid is normally retracted and then energized when the A/C is turned on, or it is energized whenever the ignition is in RUN and is retracted when you turn off the key to prevent dieseling (this was mainly used in the latter half of the 1970s). The VIN Y 307 cars DO use a vacuum actuated throttle kicker, however. The device was called an Idle Load Compensator and is the silver vacuum device at the front driver's side of the carb in this photo.
Again, what year and engine? Or, are you trying to retrofit one to a non-original application?
September 24th, 2015, 07:50 AM
#8
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in my experience the one in the photo by tru blue on the far right is the idle speed control motor. It like one Joe mentioned that when you turn on the ac it would activate. There was a wire that came off the compressor wire so that when the AC was turned on it would activate. This was also very common on Chevy engines and I believe would work to increase the idle when the ac is on'
January 15th, 2016, 07:28 AM
#9
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Looks like the one on the far right of Trueblue's pics would be the one, the intake has holes a bit forward of the carb... So not sure if that rod would reach to hit the throttle.
The engine is a 72 I believe, I bought a few cores and took the best, had machine work done... stock quad intake, non smog erra. My carb does not have any electric wires out like Joe Padavano's pics show.. So maybe it is a bit older... Will post a pic of it.
The car's original dashpot when the engine was the olds 350 came on just when the a/c was kicked on. So it was retracted when off, and extended when on. However this carb is off the older 455, and if it had the dash pot, it is no longer there.
The engine is a 72 I believe, I bought a few cores and took the best, had machine work done... stock quad intake, non smog erra. My carb does not have any electric wires out like Joe Padavano's pics show.. So maybe it is a bit older... Will post a pic of it.
The car's original dashpot when the engine was the olds 350 came on just when the a/c was kicked on. So it was retracted when off, and extended when on. However this carb is off the older 455, and if it had the dash pot, it is no longer there.
January 15th, 2016, 08:16 AM
#10
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I think the point is that anything that old has a solenoid throttle kicker, and it is on the driver's side of the carb. The dashpot, on the pass side, is for the vacuum actuated air horn secondary flaps.
I've got a solenoid one on my Chevy, and I don't know if it energizes all the time or just with the AC. I do know it sits quit nicely at 650 rpm in drive with AC off, and 600 with it on, so perhaps it is not behaving.
I've got a solenoid one on my Chevy, and I don't know if it energizes all the time or just with the AC. I do know it sits quit nicely at 650 rpm in drive with AC off, and 600 with it on, so perhaps it is not behaving.
January 15th, 2016, 09:42 AM
#11
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Good Lord.
1) Quite a manly throttle spring there.
2) How many rolls of tape should be used on the inverted flare fuel fitting for a proper seal. Said seal takes place not at the threads, but at the flare, mind you.
"I think the point is that anything that old has a solenoid throttle kicker, and it is on the driver's side of the carb. The dashpot, on the pass side, is for the vacuum actuated air horn secondary flaps. "
=========================
I believe this to be somewhat inaccurate. RH vacuum items are choke pulloff and such actuators. LH side of carb may have nothing, or the simple dashpot [allows slow motion only] shown in above pix- looks like a vacuum canister but has no nipple... or the electrical kicker upper solenoid as shown above, or the previously unknown to me vacuum twin nipple kicker upper that Joe P was kind enough to show.
No dashpots per se on the RH side, though, due to clever engineering and carful sizing of the air passage in the choke pulloff, it also serves to allow only a controlled speed relaxation of the secondary air valve keeper shutter link. I hope I am not confusing y'all with these technical terms.
PS that was a good idea, that slow release of the 2' air valve. Guess how I found that out?
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