Weber Identification & Choke Question

[Mucci]

Picked up my first 2002 a few weeks ago and step one is a tune up. The car chugs pretty hard at start up. After about 2-3 min it evens out. I assume this is a choke related issue so I have a few questions:

 

1. Does this sound like a choke issue?

2. I've found the Weber serial number but it's hard to tell if it reads DGEV or DGAV. How do you verify this by looking at it?

3. There are a couple blocked off ports on the carb. Can someone explain why they're blocked off? (I marked them with arrows)

 

The previous owner made many questionable modifications throughout the car so I'm trying to understand what's out of place and how to do it the right way. Please let me know if you see anything else out of place!

 

I apologize for how dirty it is. I'm getting there...

 

 

 

 

 

[halboyles]

First off, your carb is due for a good bath.  At least blow the outside off with carb cleaner but it also probably needs a hot tub visit and a rebuild.  There is an electric choke installed on the unit regardless what the model says it was at birth (e= electric, a=agua).  If you are having stumbling issues for a few minutes after startup then it is probably a choke issue.  Take off the top of the air filter assembly when the engine is cold.  Push the the chokes flaps down with your finger and then let go.  The flaps should return to the closed position.  Once the engine is  warmed up the flaps should be partially open at idle and then open fully when the throttle is quickly pushed down

['76mintgrün'02]

In your first photo, showing the carb's model number, the nut above that number looks quite loose.

 

I would suggest putting a wrench on all four of those nuts and snug'em up a little bit.

 

I would also make sure the screws that hold the top on are not coming out.

 

The blocked off port on the weber simply gives you the option of moving the inlet nipple to either side, then you put the plug in the other.

 

The plugged nipple at the manifold under the carb was part of the emissions system, which has been disabled.

 

 

[Mucci]

34 minutes ago, halboyles said:

First off, your carb is due for a good bath.  At least blow the outside off with carb cleaner but it also probably needs a hot tub visit and a rebuild.  There is an electric choke installed on the unit regardless what the model says it was at birth (e= electric, a=agua).  If you are having stumbling issues for a few minutes after startup then it is probably a choke issue.  Take off the top of the air filter assembly when the engine is cold.  Push the the chokes flaps down with your finger and then let go.  The flaps should return to the closed position.  Once the engine is  warmed up the flaps should be partially open at idle and then open fully when the throttle is quickly pushed down

 

Yes I agree on the cleanliness. I've got an ultrasonic cleaner for motorcycle carbs but I think this one will be too big. Is the electronic choke the relatively clean part in the 2nd photo?

If the choke flaps do not return as you say they should how do I fix that? Is it just a clean up or is there a part failing?

[Mucci]

23 minutes ago, '76Mintgrun'02 said:

In your first photo, showing the carb's model number, the nut above that number looks quite loose.

 

I would suggest putting a wrench on all four of those nuts and snug'em up a little bit.

 

I would also make sure the screws that hold the top on are not coming out.

 

The blocked off port on the weber simply gives you the option of moving the inlet nipple to either side, then you put the plug in the other.

 

The plugged nipple at the manifold under the carb was part of the emissions system, which has been disabled.

 

 

 

Ah! Good call on that loose nut. If it's inline with the rest of the PO's "mods" I'm sure it's cross-threaded.

 

What "screws that hold the top down" are you talking about? The air filter box?

 

Does the plugged nipple on the manifold under the carb indicate this car doesn't have the "reactor" and other emissions components? I've only read a little bit about guys removing all that stuff and haven't identified it all yet. I do know my "service reactor" light is on though. 

['76mintgrün'02]

I was referring to the little slotted screws that secure the top of the carb itself, underneath the air cleaner.

Those screws are amazingly soft, so try and use a screwdriver that fits them well, or they are easily deformed.

The metal the carb is made from is also soft, so don't overtighten them.  Just make sure they have not come loose.

The amount of grunge implies that fuel has been seeping out for some time.

 

That plugged nipple does imply that your engine has been de-emissioned.  

More photos of the engine bay would make it easier to identify which bits and pieces you still have.

The reactor was part of the exhaust manifold, so a photo of that might be helpful.

 

I see a vacuum dashpot/switch deal on your firewall, with no vacuum lines coming off of it.

(upper left corner of the second to last photo)

My car came that way, with things disconnected, but still under the hood.

 

Cleaning up the engine bay by removing that stuff can be satisfying, but not nearly as satisfying as cleaning that carburettor will be!

 

[halboyles]

If you think your carburetor is dirty you should see my toilet brush.  I really need to get some toilet paper:   https://www.youtube.com/watch?v=ZXMD7ktUJZY .   SFW, but not suitable for those who don't like "bad jokes."

 

The e-choke is on the passenger side of the carb behind the fuel filter hose in the attached pic.  You loosen the three flat head screws and turn it left to make the choke close tighter and right to make it close less.  You can also check the electric cable that goes from the terminal on the e-choke to the coil to make sure you have good connections.

 

That clean part in pic 2 encloses a vacuum actuated lever to open the choke flaps based on the vacuum in front of the butterflies when the throttle is opened.  It should be checked for function when you take the carb apart (which you really need to do, nudge, nudge).  But, beware, there be diagrams and o-rings in them parts.  So do your research before departing on that voyage.  An ancient map to help in navigation is attached

[Simeon]

Fuel filter looks good! 

 

where does your engine breather pipe go now? This is the pipe from the rocker cover at the top rear.   I ask because I wonder if all the dirt on the carb came from oil out of the breather. 

[Mucci]

3 hours ago, '76Mintgrun'02 said:

In your first photo, showing the carb's model number, the nut above that number looks quite loose.

 

 

Man, again, good call on that loose nut. They were all about finger tight. Some just floating. 

 

Are these choke flaps the square butterflies under the filter? I noticed there are circular butterflies deeper within with I assume are the actual throttles. When I push the square butterflies down that snap back pretty ...snappy. There's still a small gap for air to flow past (checked cold).

 

1 hour ago, Simeon said:

Fuel filter looks good! 

 

where does your engine breather pipe go now? This is the pipe from the rocker cover at the top rear.   I ask because I wonder if all the dirt on the carb came from oil out of the breather. 

 

You should have seen the old one...

The valve cover breather is just a small K&N (previous owner), and yes the area around it was pretty sludge soaked so it's possible that's where all that gunk came from. Where does that hose normally route?

 

I have a question regarding the linkage. I noticed that if I actuate the throttle by pushing down at the red arrow slightly the linkage will stick open ever so slightly to raise the idle maybe 2-300 rpm. When I actuate the throttle by twisting the rod (blue arrow) the red arrow linkage isn't engaged. Is the red arrow linkage choke related? It seems kind of sticky.

 

Is there a way to put 12V to the electronic choke to see if it actuates properly?

 

Edited February 16, 2017 by Mucci

[Simeon]

The breather hose normally goes to the air filter though that K&N style filter might not have any provision. The little filters are definitely junk but you might want to consider a catch can with something to separate oil and air between the engine and air filter.  

 

The linkage that you point to with the red arrow is part of the 'progressive' throttle that opens the secondary throttle only once the primary is about 2/3 open. That is why the 32/36 is a good street carb as the majority of your driving is done on the primary only while pootling around town. 

 

The electric choke hose is pretty simple. It works with a bimetallic strip that is heated by 12V when the car starts. In its cold state with ignition off the choke is on. As the strip is heated it bends and slowly pulls the carb linkage so that the choke opens and allows the fast idle to work down the stepped cam. 

 

The adjustment is straightforward, if you search on here you will find many posts on the subject. 

 

['76mintgrün'02]

The nut that attaches the throttle linkage may be a little loose as well.

The one right between the two arrows in your photo.

See how the little keeper tab is not aligned with a flat side, nor up tight?

You might see if you can tighten that nut up and then tap that tab back up against it...

(mine wiggled loose last fall).

 

Edited February 17, 2017 by '76Mintgrun'02