Rebuilding Weber 32/36 DGAV 33A Carburators

ECA90049 said:
I ordered another, shorter solenoid I found online for the 32/36 carb (can't find the long one anywhere) but it has a larger thread so won't fit. I've looked all over the USA, Australia, England and Italy and been told consistently that the carb I have has not been made in decades and nobody can help. In fact, you can't even find it on the historic parts list for Weber. I give up. After the first of the year, I think I will just pop for new carbs. Any recommendations?
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I believe what you have and the one I have off a 2002 is a VERY old Italian Weber carb and as I said previously the Weber expert at Worldpac had never seen one like it (I sent him your picture).
I was having issues with one of my Webers so I bought a new one. However, after talking with Worldpac, I have it working correctly. The Electronic Idle Valve you bought should be part number 43928.060 and will fit the new carbs but the new carb doesn't come with it included. Also the new Webers reportedly have physically different size jets and come standard with:
Main primary 135 secondary 140 (mine are primary 125 secondary 127 not sure are the right ones)
Air primary 160 secondary 170 (mine are primary170 secondary 175 not sure are the right ones)
idle primary 55 secondary 50 and he confirmed that the secondary is smaller. Not sure what I have.
You will need to see what you have and what should work in the new ones. Go by the parts breakdown based on the jets you have in your carbs.

@sfdon hinted at going with injectors and I am not sure what all that would take to do but is probably a very good option. Two new DGAV2336 from Carbs Unlimited with the electric idle valves will cost between $700 to $750 plus jets and gaskets.
Not sure if someone could try to take your old electronic idle valve apart and solder on a wire. I would try that or find a small diameter idle jet to try.
I will check on the 2002 carb on the car to see if I need this small idle jet and if not I will send it to you to try.
 
ECA90049 - you might try using an ordinary DGAV idle jet holder in place of that solenoid. As I understand it, that solenoid holds the idle jet in place when the car is running, but retracts the idle jet from the carb body when you shut the car off to prevent run on. If I have this right, your car should idle and run without that solenoid, albeit with a risk of run on after you shut the car off. There are two versions of idle jet holders for the DGAVs; my best guess is that you need the earlier version.

This place has them for $12.95; it may be worth a try.

Carburettor Spare Parts for Dellorto, Weber, Solex, Zenith, SU, Pierburg, Mikuni - Jets and Service Kits

More than 19.000 carburetor parts in stock, ready to ship! Dellorto Shop - CarburettorShop - RicambiCarburatori - Carburettor Spare Parts Jets and Service Kits, Carburettor Spare Parts for Dellorto, Weber, Solex, Zenith, SU, Pierburg, Mikuni - Jets and Service Kits
www.carburettorshop.com
 
Dan Wood said:
I believe what you have and the one I have off a 2002 is a VERY old Italian Weber carb and as I said previously the Weber expert at Worldpac had never seen one like it (I sent him your picture).
I was having issues with one of my Webers so I bought a new one. However, after talking with Worldpac, I have it working correctly. The Electronic Idle Valve you bought should be part number 43928.060 and will fit the new carbs but the new carb doesn't come with it included. Also the new Webers reportedly have physically different size jets and come standard with:
Main primary 135 secondary 140 (mine are primary 125 secondary 127 not sure are the right ones)
Air primary 160 secondary 170 (mine are primary170 secondary 175 not sure are the right ones)
idle primary 55 secondary 50 and he confirmed that the secondary is smaller. Not sure what I have.
You will need to see what you have and what should work in the new ones. Go by the parts breakdown based on the jets you have in your carbs.

@sfdon hinted at going with injectors and I am not sure what all that would take to do but is probably a very good option. Two new DGAV2336 from Carbs Unlimited with the electric idle valves will cost between $700 to $750 plus jets and gaskets.
Not sure if someone could try to take your old electronic idle valve apart and solder on a wire. I would try that or find a small diameter idle jet to try.
I will check on the 2002 carb on the car to see if I need this small idle jet and if not I will send it to you to try.
Click to expand...
Thanks for the help. If you do have a smaller idle jet that you don't need I will try it if you send it. Worth a shot. Thanks again...E
 
Ohmess said:
ECA90049 - you might try using an ordinary DGAV idle jet holder in place of that solenoid. As I understand it, that solenoid holds the idle jet in place when the car is running, but retracts the idle jet from the carb body when you shut the car off to prevent run on. If I have this right, your car should idle and run without that solenoid, albeit with a risk of run on after you shut the car off. There are two versions of idle jet holders for the DGAVs; my best guess is that you need the earlier version.

This place has them for $12.95; it may be worth a try.

Carburettor Spare Parts for Dellorto, Weber, Solex, Zenith, SU, Pierburg, Mikuni - Jets and Service Kits

More than 19.000 carburetor parts in stock, ready to ship! Dellorto Shop - CarburettorShop - RicambiCarburatori - Carburettor Spare Parts Jets and Service Kits, Carburettor Spare Parts for Dellorto, Weber, Solex, Zenith, SU, Pierburg, Mikuni - Jets and Service Kits
www.carburettorshop.com
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My situation with the solenoid is when the car is running (not at a stop) it runs fine. When I come to a stop it just dies. Thanks for your help...E
 
ECA90049 said:
My situation with the solenoid is when the car is running (not at a stop) it runs fine. When I come to a stop it just dies. Thanks for your help...E
Click to expand...
So, I just checked one of my Weber reference books and I had the operation of the solenoid backwards. When the solenoid receives a current flow, it retracts allowing fuel flow through the jet. When current is lacking, as when the ignition is shut off, a spring within the solenoid returns the plunger to its extended state, plugging the flow of fuel. This was an emissions device when initially introduced to prevent run-on with gasoline forumlations that were introduced at the time. Not sure whether this may still be necessary with the gasolines we use today, but the important point here is that your car will run (and idle) without the solenoid if you put an ordinary idle jet holder in its place.

Your solenoid, with the metal tab missing, will remain in the extended position blocking the flow of fuel through your idle jet because it is not getting a flow of electricity. This is why your car dies; it is only getting fuel through one idle jet on the other carb. It starts because the accelerator jet pumps fuel in, and may even idle on this fuel for a little bit. But I suspect your AFRs would be way out of whack at low revs because you are not getting fuel through one of your idle jets, which not only controls idle but also extends well into progression. The accelerator pump circuit will provide fuel when you start, upon initial acceleration, and above a certain rpm you will be getting fuel through your mains, so I can see why your car runs. Again, for $12.95, I would try an ordinary idle jet holder. Actually, if it were me, I would buy two and, if I don't experience run on problems, ditch the solenoids all together.
 
I had supervision today fine tuning the E9 after the carb rebuilds. Our Grandson Griggs (pictured) came over with his twin sister Ives.
Griggs E9.jpg
 
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In my experience both types of no -emissions idle jet holders have the coarse thread but Dan’s old solenoid has a fine thread. Dan, I’m still surprised it’s not possible to add a pig-tail onto your existing solenoid so you can hook up your Existing solenoid wire. You could remove a little bit of the insulation surrounding the broken spade to get enough surface area to solder on a pigtail. Or just drill/tap for a very small stainless machine screw that engages what’s left of the spade.
 
JFENG said:
In my experience both types of no -emissions idle jet holders have the coarse thread but Dan’s old solenoid has a fine thread. Dan, I’m still surprised it’s not possible to add a pig-tail onto your existing solenoid so you can hook up your Existing solenoid wire. You could remove a little bit of the insulation surrounding the broken spade to get enough surface area to solder on a pigtail. Or just drill/tap for a very small stainless machine screw that engages what’s left of the spade.
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John:
The long thin idle shut off valve isn't mine. It belongs to @ECA90049 and I am trying to help him by sending a small diameter idle jet to try. I think if that was my electric valve, I would try to open it up by expanding the end where the electrical tab is supposed to be and solder the end of the coil to a short length of wire. Even if this didn't work he wouldn't be out anything.
I have a long 50 from the primary side and a shorter 60 from the secondary. The Weber expert was telling me that the primary idle jet is larger than the secondary. I am not sure anything is "standard" with the Webers. I am learning much more than I ever wanted to about tuning and syncronizing the webers. I am using @Stevehose post on tuning Zenith carbs with all the tools including a Carbmate. It is very close but am getting a slight hesitation around 2800 RPM. I have a better timing light with a tachometer on order so I can measure the advance and better adjust the idle jets. An AFM might be in my future.
Thx,
Dan
 
Dan Wood said:
Weber expert was telling me that the primary idle jet is larger than the secondary
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Dan,
Sorry about getting you guys mixed up. I’m 90% sure the broken solenoid connector can be kludged because there is sure to be a pig-tail encapsulated within that LONG body.

To add to the weirdness, my 38/38’s use the big idle jet for one side and the small for the other. And … there is a shutoff solenoid one the big side(s). But as these are synchronous carbs where all four idle circuits are operating I’m really not sure why there aren’t FOUR or zero idle shutoff solenoids.
 
JFENG said:
Dan,
Sorry about getting you guys mixed up. I’m 90% sure the broken solenoid connector can be kludged because there is sure to be a pig-tail encapsulated within that LONG body.

To add to the weirdness, my 38/38’s use the big idle jet for one side and the small for the other. And … there is a shutoff solenoid one the big side(s). But as these are synchronous carbs where all four idle circuits are operating I’m really not sure why there aren’t FOUR or zero idle shutoff solenoids.
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John:
The Weber expert I spoke with mentioned that the jet thread sizes are different for the primary and the secondary on the newer Weber carbs (which I have confirmed). The jets on the secondary side are smaller.
I agree on trying to fix the broken solenoid and I think it is worth a try. The owner is on the West coast so I am not sure who out there could help him. If the male spade terminal broke off them maybe some of that is still visible.
The electric idle jets are only on the primary side which is enough to stop engine "run on or dieseling" when the ignition is turned off. That appears to be the only reason for it.
On our 2002 they are only fixed jets and not the electronic idle valves.
Idle Jets.jpg
The jet on the left (primary side) is the size equal to the new electric solenoid valves.
The one in the middle is from an old Italian Weber primary idle jet 60 size and the third one is from the same carb on the secondary side size 50.
Thx, Dan
 
JFENG said:
In my experience both types of no -emissions idle jet holders have the coarse thread but Dan’s old solenoid has a fine thread. Dan, I’m still surprised it’s not possible to add a pig-tail onto your existing solenoid so you can hook up your Existing solenoid wire. You could remove a little bit of the insulation surrounding the broken spade to get enough surface area to solder on a pigtail. Or just drill/tap for a very small stainless machine screw that engages what’s left of the spade.
Click to expand...
John - the Carburetorshop link I provided above shows two idle jet holders, in differing sizes, with the smaller one labelled as an "older" jet holder. This indicates to me that Weber used two different sized idle jet holders in the various DGA carbs over time. It is also consistent with ECA's comment that the newer style solenoid doesn't fit into the opening in the body of his carb.
 
Dan Wood said:
Thanks Steve:
Any suggestions on possible fixes? Idle mixture too lean?
Dan
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Richening the idle mix to cover is a band aid, without an AFR gauge it's pretty much a guessing game, but a 55 idle jet might get you there. Are those jet tips removeable?
 
Stevehose said:
Richening the idle mix to cover is a band aid, without an AFR gauge it's pretty much a guessing game, but a 55 idle jet might get you there. Are those jet tips removeable?
Click to expand...
Steve:
The idle jet tips in the primary with the electronic solenoid are removeable.
Thanks, Dan
 
Here is a update summary of what I learned rebuilding the Weber carbs.
1. I wish I had injectors as previously mentioned.
2. This forum is extremely valuable and I appreciate all the help I received. I reviewed all the posts about Webers and contacted a few members. If I mention names, I might missed someone - thank you for all the advice.
3. I am not sure how this car ever ran before the rebuild as the main jets were way too small. The mains were 125 and 127. The primary idle jets were different between the front and rear carbs (52 and 55). After the rebuilds, I had a very hard time getting it to run using the old jets.
Per contact with a Weber "expert" the normal standard jetting is:
Main primary 135 secondary 140 (mine were primary 125 secondary 127)
Air primary 160 secondary 170 (mine were primary170 secondary 175)
idle primary 55 secondary 50 and he confirmed that the secondary is smaller.
4. I added several tools to the collection such as AFR meter, Carbmate, and Air Flow Synchronizer which were all extremely useful.
5. Now the car is very drivable and AF ratios are good. I am planning one more change to try to clean up the cold start and idle just a little more.
Once I have the final jets in and confirm the AFR throughout the RPM range, I will post them.
 
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