Hey guys,
First off I don't think I can say enough times how thankful I am I found this website and group of people... You guys are amazing and I'm truly in all your debt. This car is my Daily Driver and I joke (but it's almost completely true) that every day I get a compliment on how cool it is and how lucky I am. Couldn't do it without you!!!
The car is a 77 and I believe the carb is an 32 ADHA. I've been having problems for a while with my choke. One weird thing btw is that I have both a Throttle control Knob and a water choke. Don't think it's an issue, just kinda funny.
Anyways, on Cold startup with the choke engaged the engine Revs to nearly 3,000 RPM. I have to stomp on the accelerator to get it to idle back down, but this simply disengages the choke. I believe the choke is functioning fine, and that something is simply out of adjustment, but am not sure. Idles fine once warm and accelerates fine (even when cold).
Thanks,
Garhett
Crazy high RPM on start up
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Daniel
Re: Crazy high RPM on start up
Hey Garhett
There's a Choke adjustment screw on the carb this holds the butterfly open during the warmup cycle
you'll need to remove the air filter housing to get to this but once it's off it should be some what easy
to adjust . I would get your hands on a Haynes book if you can find one for this car they can be very
helpful .
There's a Choke adjustment screw on the carb this holds the butterfly open during the warmup cycle
you'll need to remove the air filter housing to get to this but once it's off it should be some what easy
to adjust . I would get your hands on a Haynes book if you can find one for this car they can be very
helpful .
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garhett
Re: Crazy high RPM on start up
Daniel wrote:There's a Choke adjustment screw on the carb this holds the butterfly open during the warmup cycle
Thanks, I've messed with it before but I'll try some more. I have a shop manual but keep meaning to get my hands on a haynes.
Thanks for the suggestions!
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vandor
- Posts: 3996
- Joined: Sat May 23, 2009 1:23 pm
- Your car is a: 1971 124 Spider
- Location: Texas, USA
Re: Crazy high RPM on start up
Should be a 32 ADFA
>Anyways, on Cold startup with the choke engaged the engine Revs to nearly 3,000 RPM.
What do you do before startup? Push on the accelerator? Pull the throttle knob? To set the choke
you should push the accelerator down partway. If you do not do that, it will stay wherever it was when the engine was shut off.
>I have to stomp on the accelerator to get it to idle back down, but this simply disengages the choke.
The choke does 2 things: closes the flap above the primary barrel, and moves a cam to keep the throttle open
a bit. Maybe it is over-adjusted, so it does both of those things too much.
You can adjust it by loosening it's 3 holddown screws and rotating the round water choke housing.
BTW, the hand throttle has nothing to do with the choke. It's there so one can increase idle speed if
the engine wants to die during warmup.
>Anyways, on Cold startup with the choke engaged the engine Revs to nearly 3,000 RPM.
What do you do before startup? Push on the accelerator? Pull the throttle knob? To set the choke
you should push the accelerator down partway. If you do not do that, it will stay wherever it was when the engine was shut off.
>I have to stomp on the accelerator to get it to idle back down, but this simply disengages the choke.
The choke does 2 things: closes the flap above the primary barrel, and moves a cam to keep the throttle open
a bit. Maybe it is over-adjusted, so it does both of those things too much.
You can adjust it by loosening it's 3 holddown screws and rotating the round water choke housing.
BTW, the hand throttle has nothing to do with the choke. It's there so one can increase idle speed if
the engine wants to die during warmup.
Csaba
'71 124 Spider, much modified
'17 124 Abarth, silver
http://italiancarclub.com/csaba/
Co-owner of the best dang Fiat parts place in town
'71 124 Spider, much modified
'17 124 Abarth, silver
http://italiancarclub.com/csaba/
Co-owner of the best dang Fiat parts place in town
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Exit98
Re: Crazy high RPM on start up
garhett,
"Crazy High RPM on Start Up"
The guys that already answered your post have given you the answer. But just in case I'd like to make a couple simple points.
You only have one choke, the one on the carb. The gismo labled "throttle" that you are pulling on when you start the car is not a choke. It is a cable that simply opens up the throttle linkage. That is why you are getting "Crazy High RPM". Its like you are holding down the gas pedal. Don't use it, push it in and forget it. Let's just skip the discussion of the value of this silly thing for the time being. It's not much. Some people call it a poor man's cruise control. Don't go there.
I've got a water choke on my 76. It works fine and your's probably does too.
Cold start:
Turn on key to accessory, let the fuel pump pump a couple seconds
Depress clutch
Depress throttle pedal one time to floor and release
turn key to engage starter
The car will start and as the engine warms up a little the idle will increase up to about 2500 rpm after a few minutes. If you just let it run and don't drive away, as the water temp rises the choke will slowly close until it is completely disengaged. In actual use you can begin driving and the idle will come down. If it is revving too high just kick the pedal and it will partially or fully disengage the clutch.
Incidentially, depressing the clutch on start up is more important than you might think. If you start the car without the clutch depressed but in neutral the starter motor has to turn not only the engine in cold oil, but also the thick heavy oil in the transmission too, since with the clutch out the transmission input shaft is turning. Back in the day when we drove our Spiders as every day cars knowing this trick was essential, particularly if the temperature was 20 degrees and the battery was weak. You’d get one shot to start the car on a cold morning. Mess up and you’d be looking for a jump. Try it both ways and you’ll see. The starter turns over slower if the clutch engaged rather than disengaged.
Even more important though since our Spider’s don’t have a safety switch like modern stick shift cars if you forget and start the car in gear with the clutch out you won’t be happy with the result. Back in the late 60’s I saw a guy with a brand new Porsche 911 drive it into a garage door off the starter. It wasn’t pretty.
"Crazy High RPM on Start Up"
The guys that already answered your post have given you the answer. But just in case I'd like to make a couple simple points.
You only have one choke, the one on the carb. The gismo labled "throttle" that you are pulling on when you start the car is not a choke. It is a cable that simply opens up the throttle linkage. That is why you are getting "Crazy High RPM". Its like you are holding down the gas pedal. Don't use it, push it in and forget it. Let's just skip the discussion of the value of this silly thing for the time being. It's not much. Some people call it a poor man's cruise control. Don't go there.
I've got a water choke on my 76. It works fine and your's probably does too.
Cold start:
Turn on key to accessory, let the fuel pump pump a couple seconds
Depress clutch
Depress throttle pedal one time to floor and release
turn key to engage starter
The car will start and as the engine warms up a little the idle will increase up to about 2500 rpm after a few minutes. If you just let it run and don't drive away, as the water temp rises the choke will slowly close until it is completely disengaged. In actual use you can begin driving and the idle will come down. If it is revving too high just kick the pedal and it will partially or fully disengage the clutch.
Incidentially, depressing the clutch on start up is more important than you might think. If you start the car without the clutch depressed but in neutral the starter motor has to turn not only the engine in cold oil, but also the thick heavy oil in the transmission too, since with the clutch out the transmission input shaft is turning. Back in the day when we drove our Spiders as every day cars knowing this trick was essential, particularly if the temperature was 20 degrees and the battery was weak. You’d get one shot to start the car on a cold morning. Mess up and you’d be looking for a jump. Try it both ways and you’ll see. The starter turns over slower if the clutch engaged rather than disengaged.
Even more important though since our Spider’s don’t have a safety switch like modern stick shift cars if you forget and start the car in gear with the clutch out you won’t be happy with the result. Back in the late 60’s I saw a guy with a brand new Porsche 911 drive it into a garage door off the starter. It wasn’t pretty.
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garhett
Re: Crazy high RPM on start up
SOLVED!!!
Adjustment screw on choke became loose somehow. So no matter what I adjusted it to, once I drove it again, it worked itself, all the way "out". Threw some thread lock on there for now and works like a charm
On a lighter note, the other day I went out to adjust it in the morning and was veeeeery absent minded and started it in gear.
Needless to say, with the choke engaged she cruised across the garage floor and into the wall, smashing my brand new bicycle in between...
Put a real good dent in the hood and bent my bicycle frame up pretty good too
...
Popped the dent out pretty good for now, hard to even notice but did take some paint off leaving the primer.
Bicycle was repaired via a come-along and some farmer ingenuity on my Father's side
Adjustment screw on choke became loose somehow. So no matter what I adjusted it to, once I drove it again, it worked itself, all the way "out". Threw some thread lock on there for now and works like a charm
On a lighter note, the other day I went out to adjust it in the morning and was veeeeery absent minded and started it in gear.
Needless to say, with the choke engaged she cruised across the garage floor and into the wall, smashing my brand new bicycle in between...Put a real good dent in the hood and bent my bicycle frame up pretty good too
...Popped the dent out pretty good for now, hard to even notice but did take some paint off leaving the primer.
Bicycle was repaired via a come-along and some farmer ingenuity on my Father's side