Low rpm problems, float maybe?

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Texsardo
Posts: 216
Joined: Fri May 09, 2014 1:15 am
Your car is a: 1978 Fiat Spider Convertible 1800
Location: Post Falls, Idaho
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Low rpm problems, float maybe?

Post by Texsardo »

Rebuilt carburetor 32 adfa, 1978 1800. Ran like craps after first start up. First cold start went perfect but it surged really bad. Found a vacuum tube I had left uncapped. OK, again starts immediately. But test drive had a sputtering start until 3rd gear and around 3000 rpm. After 3rd it runs like a bat out of hell. Floor it and it jumps like a Tiger. Back down to low rpm , 2nd gear, below 3000 and is sputtering like a drowning man. Checked every way possible for vacuum leaks, none. Idle' s at 800-900rpm with minor surging.
Anyone think I may have been off on my float measurement? I did not replace or touch any jets.It is getting fuel just fine from see through filter. Increasing with accelerator rod slowly it seems to be OK. Fast and it pop's once then gitty up and go.
Open to suggestions before I take it apart again. O yeah, when advancing accelerator and looking down primary, I can see the the gas dribbling from nozzle.
Texsardo
vandor
Posts: 3996
Joined: Sat May 23, 2009 1:23 pm
Your car is a: 1971 124 Spider
Location: Texas, USA

Re: Low rpm problems, float maybe?

Post by vandor »

What is the ignition timing? Did you check that it increases advance gradually as rpm increases?
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
User avatar
Texsardo
Posts: 216
Joined: Fri May 09, 2014 1:15 am
Your car is a: 1978 Fiat Spider Convertible 1800
Location: Post Falls, Idaho
Contact:

Re: Low rpm problems, float maybe?

Post by Texsardo »

Thanks, yes. I have it at TDC (it's a late 78 model, Fiat kinda made it half 78 and half 79) as there are 2 suggestions for this.
Some say 10°BTDC and the other is 0° etc. So I thought I can't go wrong with using physics to decide 0°. But yes I checked that, it does advance as acceleration increases plus checked points, spark plugs, spark plug wire are new. I have had some difficulty sorting out the vacuum lines. I had photo of what was attached when I bought it. Put in carb rebuild kit, followed everyone's advice on tuning, float level, etc. So I put it back like that. Then internet showed 32adfa and where canisters lines vacuum line, etc and discovered some were wrong. Then there is the forum showing how everything plugged except charcoal canister. At this point I don't know what really goes where. I am sure about the 2 canister lines but the rest??
I don't have original breather, it is the rectangular and the crankcase tube has a filter attached. So every other line (5) who knows. . Mainly I see a lot of diagrams for adf
not adfa. By the way, Idaho has no smog requirements so all the extra sensors, tubes, etc have been removed or capped off.
Texsardo :mrgreen:
vandor
Posts: 3996
Joined: Sat May 23, 2009 1:23 pm
Your car is a: 1971 124 Spider
Location: Texas, USA

Re: Low rpm problems, float maybe?

Post by vandor »

> Some say 10°BTDC and the other is 0° etc.

0 is factory setting, it was for emissions. For a well running car use 10 degrees.
It will have too much advance at high rpm, but with the low stock compression it does not really matter.

> I have had some difficulty sorting out the vacuum lines.

You don't need any! Plug it all off except the one for the brake booster.

BTW, your symptoms could also be caused by too much valve overlap, so cam timing may be off or camgears may be in the wrong position.
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
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