32 ADFA carb problem

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Scotsman

32 ADFA carb problem

Post by Scotsman »

I had lost idle control on my 77 Spider and found my float full of fuel. I stripped and cleaned jets, replaced float, needle and seat, diaphragm and idle mix screw with the help of the nicely illustrated guide of JSeaman http://www.mk3supra.org/topic/561-guide ... -dgav-carb.
Engine started immediately and I reset throttle controls on an open choke as described by Brad Artigue. When I started from cold with choke closed, it did not go on fast idle but the choke opened fully as engine warmed. Engine idled reasonably well with fuel appearing to come from the progression holes, but it no longer transitioned to the main jet. When I increased throttle, it coughed badly and sucked air from the hole where the screw on the lever ( Bruce's parts 56-58) enters. Manually working the throttle also gave no fuel from the main jet. The idle solenoid tested OK and I found no leaks by spraying carb cleaner around carb.

Could I have reset the throttle linkage on the wrong cam and if so how should this be done correctly? Or should I take the carb off again to check other parts?

After 38 years of happy driving, I would like to get my baby running again. Any help for this mechanically challenged old fogie would be greatly appreciated.
Thanks.
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: 32 ADFA carb problem

Post by bradartigue »

That is one ambitious rebuild guide. Very detailed indeed.

When the choke is "on" (flap closed) the choke assembly should slightly move the throttle assembly open, increasing the idle speed.

What is this hole you describe as Bruce's 56-58? There should be no holes open, anywhere, except the air correctors on the top of the carb.
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: 32 ADFA carb problem

Post by bradartigue »

Also - that's a DFAV rebuild guide, your title is ADFA.
Scotsman

Re: 32 ADFA carb problem

Post by Scotsman »

Brad

Thank for your reply.

Sorry about choke "open/closed" nomenclature. I am no mechanic, but you say on p35 of your excellent guide to block choke "open" when setting idle. My point is that choke plate reaches almost vertical when engine warms up so presumably that mechanism is OK. My original owners handbook ( copies available ) says I have a 32ADFA 14 and my parts # came from ADF schematic from your article.

The hole I referred to is where a screw on a throttle lever enters to rest on what I think is the choke actuating lever. This hole is beneath and behind the hot water intake. Have photo but can't figure out how to include it here.

Before my 'fix' I had fuel at the nozzles that responded to the throttle in both barrels. Now I don't. So, how can I now have fuel at idle but not on main throttle? Why the failure to progress from idle to the main throttle or the lack of fuel at the nozzle when I manually activate the throttle?

I suspect I have done some dumb thing in reassembling carb but am hoping there is a simpler explanation due to throttle linkage settings. Any suggestions?

Thanks
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RoyBatty
Posts: 852
Joined: Sat Aug 28, 2010 11:44 pm
Your car is a: 1975 124 Spider - 1971 124 Sport Coupe
Location: Locust Grove, VA

Re: 32 ADFA carb problem

Post by RoyBatty »

Sounds like you have an issue from the accelerator pump circuit or discharge nozzles.
Can you post a picture of the top of your carb and point out where you are talking about?
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RoyBatty
Posts: 852
Joined: Sat Aug 28, 2010 11:44 pm
Your car is a: 1975 124 Spider - 1971 124 Sport Coupe
Location: Locust Grove, VA

Re: 32 ADFA carb problem

Post by RoyBatty »

Email pictures to me and I'll pay then up here for you.
Scotsman

Re: 32 ADFA carb problem

Post by Scotsman »

Hello Brad and Roy

Many thanks for your info.

The hole where the great sucking sound seems to come from when I increase throttle is where the fast idle adjustment screw enters the carb body on the housing for the hot water choke system.

I did replace the diaphragm. The throttle linkage seems to cycle OK manually. Does it reset automatically on the correct cam?

Is there anything I can try before taking off the carb again to check the diaphragm / accelerator mechanism?
Thanks
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: 32 ADFA carb problem

Post by bradartigue »

There should not be a hole. You have an adjustment screw in the center of it. If it is sucking air around the body then something is missing (the diaphragm?)

http://www.artigue.com/fiatcontent/carbs/32_ADF.pdf

Figure 4 explains the fast idle capsule operation and shows the assembly.
Scotsman

Re: 32 ADFA carb problem

Post by Scotsman »

Can't get my IPad to insert pic but here is link Http://s1341.photobucket.com/user/Ediscot/library. to the hole where the screw enters. Chilton calls it the fast idle adjusting screw or linkage. Hope it works.
Scotsman

Re: 32 ADFA carb problem

Post by Scotsman »

Found the problem, at least part. It was me. In removing the carb I opened the cap at the gas tank to avoid fuel spills. Forgot to put it back on after I put carb back. Think this may explain the great sucking sound and lack of gas when opening throttle.

Old age is a disease to be avoided, hope for a vaccine!!!

I still have problems with fast idle but will address these separately.

Many Thanks for suggestions and help.
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