34 ADF rebuild and fitment

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MrJD
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Your car is a: Looking to ask questions about a 79 2.0
Location: Laurinburg NC

34 ADF rebuild and fitment

Post by MrJD »

As i have said, I am not a carb guy at this point, but I plan to learn all about the concept in this process. the goal of this thread will be walk through the rebuild and fitment process of the 34ADF to later spiders (like my 79 for instance) using a single plane manifold. I ordered my carb from europe (Cyprus to be specific!) and it came in today. There are some pretty funny things going on, but it is all there. Check it out.... this is compared to a 32ADFA that I will use for some parts (like the obvious missing spring and interesting screw they are using.

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32 left, 34 right
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swapped
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Payed $130 shipped. How'd I do? Rebuild kit should be here in the next couple of days.
Last edited by MrJD on Mon May 05, 2014 1:11 pm, edited 1 time in total.
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bradartigue
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Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: 34 ADF rebuild and fitment

Post by bradartigue »

Needs a good scrubbing!

I would buy a can of foaming engine cleaner and spray it down with it, then scrub with a toothbrush and repeat until the exterior is clean. Follow-up with carburetor clean to dry it off, inside and out. Once dry spray the bolts and various moving bits with PBlaster (or any penetrant) to make disassembly easy.

When you disassemble just stay organized and clean. I like those big gallon jugs of carb cleaner with the basket. Take a lot of digital pictures as you remove things and make note of what came out of what hole/etc. The only part I rarely remove are the throttle plates as I find the screws are typically ruined on removal and they are not necessarily serviceable on an ADF, nor are the shafts. Leave them in and keep them clean.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

Brad, any comment on running an electric choke vs water?

Also, do I need to leave any of the ports on the intake manifold open? If i run an electric choke, I can close off everything if I am not mistaken.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

had time for a little disassembly and cleaning. Looks like i need to order some jets...

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Solex made jets. interesting.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

First, things are basically ready to go back together! (going to be fun figuring out all the O-rings!)
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I cleaned the hell out of everything with degreaser and bought a bottle of carb cleaner. Going to spray the hell out of every opening tomorrow to make sure it is 100% clear before putting it back together.

First, some comments: Having an extra 32adfa around to pull parts off of is Very nice. I was able to pull the vac port from the base of the 32adfa and drill/press that port INTO the 34adf for my distributor. It was an easy task in reality. Also, the adfa had some jets I needed for the set up recommended to me. The follwing is what I desire

Weber 34ADF 15/150 jetting
: Main venturis 24/26
: Aux Venturi 4.5/4.5
: Main jets 120/140
: Emulsion tubes F11/F75
: Air Correctors 140/180
: Idle jet 47/90
: Pump Jet 40
: Float Valve 1.75

Here are my issues. I can run the 120/140 for main jets, but I will have to mix my BRANDS of jet. I have two solex mains but they are 120 and 125. My other jets i suppose are weber factory, and they are 125/140. See below for images of how different they are
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I am told 130/140 is also acceptable, so I am thinking I will just use the 125/140 so the jets are of the same style.

Also, the recommended idle jetting is 47/90. I have an appropriate 90, but the 47 I have is just a screw! It doesn't have an ICU solenoid. I pulled the ICU solenoid off of the 32adfa and it has a 50 jet.
Here is the ICU and just the screw. I have no idea if I can just run the screw or if the solenoid is required....
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Last but not least... In the barrels of the carb there are some rough areas where the casting originally formed. You can see rings in the barrels in this image:
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Should I go in and smooth everything out, or leave it alone? My instincts tell me to make it smooth... but compared to a HUGE choke flap causing turbulent flow, I doubt minor imperfections in the venturis are that huge of a deal.

Opinions?

Also, if you know more than I do, do I need any of the big ports that are open on the back of the single plane manifold? I'd love to get to work on it soon.
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bradartigue
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Re: 34 ADF rebuild and fitment

Post by bradartigue »

MrJD wrote:Brad, any comment on running an electric choke vs water?

Also, do I need to leave any of the ports on the intake manifold open? If i run an electric choke, I can close off everything if I am not mistaken.
It doesn't really matter but the electric choke is much smaller and you don't have hoses full of water running into your carburetor. I've never had an issue with either type. If you go electric then the only manifold port you need is for the brake booster. Otherwise you need the brake booster and choke water pipe.
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bradartigue
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Re: 34 ADF rebuild and fitment

Post by bradartigue »

Oh and on the carb barrel, absolutely not. You stand a high chance of ruining the carburetor even if you are careful - the tolerances are tiny and the material very soft. Turbulence inside the carburetor at the stage you see those casting marks isn't relevant, some would argue it is beneficial.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

I tested the water choke and it works perfectly, so I am going to use it. What about the idle solenoid vs screw? Mixing different brands of jets?

It is 100% done in terms of teardown and cleaning. I am going to put it back together starting friday night.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

images:
http://i14.photobucket.com/albums/a309/ ... 11cba8.jpg
http://i14.photobucket.com/albums/a309/ ... a508bc.jpg
I've not checked my tuning guides yet, but anyone care to comment on setting these two screws?
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getting assembled
http://i14.photobucket.com/albums/a309/ ... efed08.jpg
http://i14.photobucket.com/albums/a309/ ... 065bec.jpg

These two parts were NOT included with my rebuild kit. Glad they were in good order as I had to re-use them
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retaining clip in
http://i14.photobucket.com/albums/a309/ ... a70942.jpg

http://i14.photobucket.com/albums/a309/ ... 5bea14.jpg
top ready to go on
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used the throttle assembly off of the 32adfa I had laying around
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http://i14.photobucket.com/albums/a309/ ... 0821aa.jpg

had a weird issue with the carb not wanting to close fully after opening. I rubbed some grease into the contact surfaces and polished a few spots in the barrels and it works now

fully together
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Best part, I have under $200 in this carb presently. :)

Still dunno what I am going to do about my idle jet issue...
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bradartigue
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Re: 34 ADF rebuild and fitment

Post by bradartigue »

The solenoid is not required, it is there to prevent dieseling. With the high octane fuels available today this is unlikely to occur.
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bradartigue
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Re: 34 ADF rebuild and fitment

Post by bradartigue »

bradartigue wrote:The solenoid is not required, it is there to prevent dieseling. With the high octane fuels available today this is unlikely to occur.
Oh and don't use those Solex jets. Use Weber jets. The Solex ones are a different shape and might not sit correctly, allowing some fuel to slip by and goofing up your mix. You can buy Weber jets from lots of places.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

Cool, thanks Brad. Looks like I made the right decisions, lol. Expect more questions when it comes time to fit it to the car. The 79 has so much crap for emissions... I dunno what I need and what I don't!
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toplessexpat
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Re: 34 ADF rebuild and fitment

Post by toplessexpat »

Nice job on this. There's nothing better than the cathartic happiness brought about by bringing old parts back to life. Thanks for posting!
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bradartigue
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Re: 34 ADF rebuild and fitment

Post by bradartigue »

MrJD wrote:Cool, thanks Brad. Looks like I made the right decisions, lol. Expect more questions when it comes time to fit it to the car. The 79 has so much crap for emissions... I dunno what I need and what I don't!
That's really easy, once you swap out the manifold with one from an 1800 then everything that won't reconnect you remove. All of the manifold-rigged plumbing, the EGR, it all comes off when you take off that manifold. Then all you're left with is fuel lines (in and out), vapor lines (to/from charcoal canister), brake booster, water choke lines, and the distributor vacuum line. You'll be amazed how much room you gain in the engine bay with the 2000 intake manifold gone.

If you retain the original 79 exhaust (most 79s are 4-2-1 and there is nothing wrong with them) you'll have the EGR port open. I usually cut the pipe and you can insert one of those valve cover retainers - just like the four you have installed - with some JB weld and seal it off. The hole in the 2000 head where the EGR was can remain as nothing will be passing through it on either side.
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MrJD
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Re: 34 ADF rebuild and fitment

Post by MrJD »

easier said than done. :)

I've got the general idea, but there are lots of valves and things associated with the head that are confusing as hell. Dunno what to plug and what to vent at this poing (will come later).

Next month I am ordering an air filter set up as I don't care for the stock one (can't get at the carb for tuning which nearly left me stranded when I had first bought it). I like the LOOKS of the foam filters like this:
http://www.autoricambi.us/PDGImages/FT0-465-Z.jpg

but I know its probably better to do a paper filter like this
http://www.autoricambi.us/PDGImages/FT0-432-Z.jpg

as you can probably find a replacement at any autozone or whatever you come across in an emergency.

Opinion?
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