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Discussion Starter · #1 ·
While checking the jets on a "backup" weber (32/36 DVAG) I discovered that the idle jet "holder" (screw) on the primary is larger than the "holder" on the secondary, and the jets, although numbered the same (#50), they are different in shape and size. See the attached photo. The primary idle jet and holder is on the right and secondary on the left. The primary jet has three holes in it and the diameter of the holder shaft is 8mm, where the secondary has just two holes with a 6mm diameter holder, as do all other the idle jets on my other two carburators -- and the idle jet holders are the same size -- interchangeable -- on my other carburators.

Obviously, a previous owner modified the primary idle jet by enlarging the idle jet orfice to accommodate a larger idle jet. What jet was used ? It didn't come from a 38 DGAS. What performance -- or lack of -- should be expected? (Note: I don't have a running Opel to test it) The other jets were:
Primary: main 140; air 170; idle 50 (modified)
Secondary: main 155; air 160; idle 50

Anyone have any ideas or clues ....??

Thanks ..

Ken
 

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Ken,

The 32/36 dgev & dgav use different size idle jets & holders. The 38 Webers are also this way. The 32/36 manual choke Webers use the same smaller size jets & jet holders on both sides. Many of the online Weber parts sources will ask if you need one of each or both the same. Some of the older carbs may have used just the smaller jets on both sides.

~ Tom C.
 

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Actually, I believe that the early Webers used a small jet holder and the later used a large jet holder. I have a later model and it uses the larger holder. I wasn't aware of some using two different sizes on the same carbureter. OGTS keeps idle jets for both sizes.
 

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Later carb larger primary jet/holder

Dmcbrass said:
Actually, I believe that the early Webers used a small jet holder and the later used a large jet holder. I have a later model and it uses the larger holder. I wasn't aware of some using two different sizes on the same carbureter. OGTS keeps idle jets for both sizes.
Believe they were redesigned to allow for use of an ICO solenoid (EPA), which won't fit the early, small jet/holder carbs.
 

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Discussion Starter · #6 ·
Thanks All ...

Learn something new everyday. I thought I had stumbled onto a "weber aberration." I've owned four webers -- bought one new (1980) -- and the primary and secondary idle jet holders on all four are the same size -- except the most recent acquistion, referenced above -- and all are DGAV's. The new weber I bought came with a water choke (I later converted it to an electric choke) and the others had electric chokes.

Is there any perfomance advantage in having the weber with the "odd-ball" primary idle jet?

Ken
 

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Idle jet holder sizes

svopel said:
Thanks All ...

Learn something new everyday. I thought I had stumbled onto a "weber aberration." I've owned four webers -- bought one new (1980) -- and the primary and secondary idle jet holders on all four are the same size -- except the most recent acquistion, referenced above -- and all are DGAV's. The new weber I bought came with a water choke (I later converted it to an electric choke) and the others had electric chokes.

Is there any perfomance advantage in having the weber with the "odd-ball" primary idle jet?

Ken
In a word, NONE! Metering is based on jet orifice size and has nothing to do with the jet holder threaded diameter. ALL idle/transition fuel passes through and is metered by the jet orifice, so whether it's held in place by a 6mm or 8mm threaded holder is irrelevant.
 

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ALL idle/transition fuel passes through and is metered by the jet orifice, so whether it's held in place by a 6mm or 8mm threaded holder is irrelevant.
I understand that the holder itself wouldn't affect performance. The reason for my question about performance is that the larger holder has a larger jet, which has three metered orifices whereas the smaller holder/jet has only two metered orifices.

Thanks ...

Ken
 

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"Idle jet" metering and metered orifices

svopel said:
ALL idle/transition fuel passes through and is metered by the jet orifice, so whether it's held in place by a 6mm or 8mm threaded holder is irrelevant.[/QUOTE]

I understand that the holder itself wouldn't affect performance. The reason for my question about performance is that the larger holder has a larger DIAMETER jet, which has three metered orifices whereas the smaller holder/jet has only two metered orifices.

Thanks ...

Ken
You are confusing the SINGLE "metering" (controlling input) orifice in the tapered end of the jet with the MULTIPLE "metered" (output) orifices in the sides of the jet. The "jet's" fuel flow is completely controlled by the single "metering" orifice, regardless of the number of "metered" orifices used (i.e. flow is into the single end orifice and out the multiple side orifices), OK? :D
 
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