Weber ADF high rpms

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gjonsey
Posts: 27
Joined: Sun Sep 24, 2017 11:44 pm
Your car is a: 1976 124 Spider

Weber ADF high rpms

Postby gjonsey » Tue Sep 26, 2017 3:01 pm

Hi all.

After purchasing a 75 124, I realized that, although it drove well, it spat soot like crazy. It turned my grass black in under a minute! I removed the Weber ADFA carb, and made some adjustments. Two carb fires later I had it idling with the "throttle" lever pushed in, and the air cleaner on.

The problem? It revs at 2,000 rpm and dies (or drops tons of power) with a push of the throttle. It ran (rich) but well before I messed with it... :evil:

There is also a hose that runs from the fuel overflow on the carb that runs to the gasoline vapor filter, which leaks like crazy from a small circular hole on the bottom.

ANY HELP?!
Thanks in advance :D

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Nanonevol
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Joined: Thu Nov 13, 2014 9:17 am
Your car is a: 1977 Fiat 124 Spider
Location: Medway, Massachusetts

Re: Weber ADF high rpms

Postby Nanonevol » Tue Sep 26, 2017 3:18 pm

Have you had the carb apart at all and checked things like float level?
1977 Fiat Spider
1985 Jaguar XJ6
1967 Triumph Bonneville (hard-tail chopper)
1966 BSA Lightning

wubie317
Posts: 76
Joined: Mon Mar 03, 2014 3:54 pm
Your car is a: 1977 Fiat Spider
Location: Sonoma, CA

Re: Weber ADF high rpms

Postby wubie317 » Tue Sep 26, 2017 8:01 pm

gjonsey wrote:Hi all.

After purchasing a 75 124, I realized that, although it drove well, it spat soot like crazy. It turned my grass black in under a minute! I removed the Weber ADFA carb, and made some adjustments. Two carb fires later I had it idling with the "throttle" lever pushed in, and the air cleaner on.

The problem? It revs at 2,000 rpm and dies (or drops tons of power) with a push of the throttle. It ran (rich) but well before I messed with it... :evil:

There is also a hose that runs from the fuel overflow on the carb that runs to the gasoline vapor filter, which leaks like crazy from a small circular hole on the bottom.

ANY HELP?!
Thanks in advance :D


Are you sure you have the hoses right? I'll post a pic of my ADFA and the hoses (I'm pretty sure this is correct, but not 100%...my car runs great!)

I can never get images to post...try this https://flic.kr/p/BMHtDy. By the way, the top #6 should be #7...and it goes to the fuel return (mine runs along driver side, back to the gas tank), not the canister!

gjonsey
Posts: 27
Joined: Sun Sep 24, 2017 11:44 pm
Your car is a: 1976 124 Spider

Re: Weber ADF high rpms

Postby gjonsey » Wed Sep 27, 2017 12:49 pm

Nanonevol wrote:Have you had the carb apart at all and checked things like float level?


Yep, carb floats seem to work.

gjonsey
Posts: 27
Joined: Sun Sep 24, 2017 11:44 pm
Your car is a: 1976 124 Spider

Re: Weber ADF high rpms

Postby gjonsey » Wed Sep 27, 2017 12:53 pm

wubie317 wrote:
Are you sure you have the hoses right? I'll post a pic of my ADFA and the hoses (I'm pretty sure this is correct, but not 100%...my car runs great!)

I can never get images to post...try this https://flic.kr/p/BMHtDy. By the way, the top #6 should be #7...and it goes to the fuel return (mine runs along driver side, back to the gas tank), not the canister!


Image link does bot work. Can you message it to me? Otherwise my email is gtjonsey99@gmail.com

wubie317
Posts: 76
Joined: Mon Mar 03, 2014 3:54 pm
Your car is a: 1977 Fiat Spider
Location: Sonoma, CA

Re: Weber ADF high rpms

Postby wubie317 » Wed Sep 27, 2017 1:14 pm

Here's the image. IMGUR seems to be the one that works.

By the way, if you've been running gas into your vapor canister, I think I'd pull it out and replace it. Or open it up...I believe there are how-to's on replacing the carbon with fish tank stuff. Seems like a fire hazard for sure!

Image

gjonsey
Posts: 27
Joined: Sun Sep 24, 2017 11:44 pm
Your car is a: 1976 124 Spider

Re: Weber ADF high rpms

Postby gjonsey » Thu Sep 28, 2017 3:00 pm

wubie317 wrote:Here's the image. IMGUR seems to be the one that works.

By the way, if you've been running gas into your vapor canister, I think I'd pull it out and replace it. Or open it up...I believe there are how-to's on replacing the carbon with fish tank stuff. Seems like a fire hazard for sure!

Image


Everything is working! Sort of...
Which line is the fuel return? I have 3 lines, the one on the drivers side is to the pump, I assume the middle is fuel return, and the outside right isn't hooked up to anything, just a hose hanging there.

Where is the "thermo switch t" located at?
And I cannot locate am air cleaner...
The vapor canister still has one nozzle on the side that has no hoses on it. Any ideas?

The engine runs very high rpm with no power loss when I step on the gas. Might this be a vacuum leak?

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Nanonevol
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Your car is a: 1977 Fiat 124 Spider
Location: Medway, Massachusetts

Re: Weber ADF high rpms

Postby Nanonevol » Thu Sep 28, 2017 5:27 pm

gjonsey wrote:
Nanonevol wrote:Have you had the carb apart at all and checked things like float level?


Yep, carb floats seem to work.


But are they set at the right height?
High idle and the power loss both sound like carb problems. Wondering if you've had it apart and cleaned and set to specs.
The "throttle" knob under the dash is kind on useless in my opinion if the carb is working correctly. I'd keep it pushed in.
1977 Fiat Spider
1985 Jaguar XJ6
1967 Triumph Bonneville (hard-tail chopper)
1966 BSA Lightning

wubie317
Posts: 76
Joined: Mon Mar 03, 2014 3:54 pm
Your car is a: 1977 Fiat Spider
Location: Sonoma, CA

Re: Weber ADF high rpms

Postby wubie317 » Mon Oct 02, 2017 12:25 pm

Since your ADF is a bit older than mine, I'm guessing there are a few differences.

I have heard that some carbs don't have the nipple marked '4' on my image. Thus, you might not have the thermo switch. Mine is a switch that's mounted into the intake manifold, just 'behind' the carb as you look at it from the driver side. It has a hose that runs to a T, one side comes from another electro switch on the driver side, the other side ends at what I think is a vacuum advance on the passenger side (part of the emissions system, as far as I know...Do you still have all that equipment?).

My fuel lines are 'stacked'...for me, the return is on the top and the bottom goes to the fuel pump. Why you have 3 lines is beyond me, though I have some metal lines that go into my brake booster (which I know nothing about, TBH)

On the under side of my air cleaner, I've got a small nipple...that one is connected to '3'

My vapor canister has a nipple on the top and one on the side, low down. I call that one the 'bottom'. It goes to #1.

As for your high RPMs, I think you might still have unwanted air getting into the carb especially if you have some hoses that aren't connected to anything. I'd start with getting everything connected correctly, then make sure that none of your vacuum hoses are old and cracked. If none of that helps, I'd take the carb back out and do all the bench adjustments (I can send you the docs I have, though they're tough to read).

Everything is working! Sort of...
Which line is the fuel return? I have 3 lines, the one on the drivers side is to the pump, I assume the middle is fuel return, and the outside right isn't hooked up to anything, just a hose hanging there.

Where is the "thermo switch t" located at?
And I cannot locate am air cleaner...
The vapor canister still has one nozzle on the side that has no hoses on it. Any ideas?

The engine runs very high rpm with no power loss when I step on the gas. Might this be a vacuum leak?

gjonsey
Posts: 27
Joined: Sun Sep 24, 2017 11:44 pm
Your car is a: 1976 124 Spider

Re: Weber ADF high rpms

Postby gjonsey » Fri Oct 06, 2017 2:14 pm

Hmm... This is all a bit complicated for descriptions. I was considering making a YouTube channel where I do a complete overhaul of the car. Perhaps this would allow for a good visual aid? Ideas?

131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: Weber ADF high rpms

Postby 131 » Mon Oct 16, 2017 11:04 pm

Do you have 12v at the idle stop solenoid? With the ignition on, remove the wire and you should hear the solenoid disengage, if it's not working you get no fuel through your idle circuit and the throttle has to be adjusted so it runs on the main circuit.
Mick.

'82 2litre 131, rally cams, IDFs & headers.


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