Today I found out my recently bought 2002 has a weber 2002 carb.
But when I throttle only one barrel opens, by using my hand I manually turn the second one(not opening) it revs better.
Why doesnt my second barrel (driver side) open???

Please help.

for one its not under load, so it will act differently anyway, two your aren't flooring it. to my knowledge the second (bigger) bbl doesn't open unless your really raggen it, like pedal to the floor when acc. that kind of thing. this is better because it uses less gas when you are just cruzing. i could of course be wrong, someone correct me if i am.

After researching a lil bit, I found out it is a secondary barrel. I tried flooring it but it doesnt show movement in the second barrel. Can this be done manually?

If it is a DGV then the secondary doesn't open until about 3/4 throttle and opens fully at full throttle. If yours doesn't open, it is either adjusted wrong, or the linkage is not connected. Trust that it should work and check out the linkage.

Jose

If it is a DGV then the secondary doesn't open until about 3/4 throttle and opens fully at full throttle. If yours doesn't open, it is either adjusted wrong, or the linkage is not connected. Trust that it should work and check out the linkage.

Jose

It seems to me that the linkage is not connected, Does someone have a diagram to how it supose to look? What can I check to make sure?

Would the same logic apply to the Solex 32/32 DIDTA 2 bbl??
T

Do you have a pic? It doesn't sound like my 32/36.

I don't have any pics. right now, but try this link.

http://www.carburetion.com/diags/3236DGVDiaginfo.asp



Jose

Weber carbs came in many configurations not only in size of venturii but also how and when the secondary would open.

INHO nothing can substitute the sound of a WOT set of properly tuned carburators, well the sound of the individual throttle bodies on the M series might come close.

Three main types vacuum, linkage or concurrent.
If the venturii are of different sizes they would use vacuum or linkage, if both venturii are of the same size they could vacuum, linkage and also open concurrently.

Concurrently, I don't think an explanation is needed :) they open together.
This link shows a linkage style secondary http://www.carburetion.com/diags/3236DGVDiaginfo.asp
Here you can also find some history on weber http://en.wikipedia.org/wiki/Weber_carburetor


Linkage, starts to open when main is about 60% to 70% open (this can be adjusted) with this method the secondary will open completely during the remaning cycle of the primary, this method will open both at your command, you control it with your foot.

Vacuum, the secondary in this setup is opened by a vacuum diaphram under certain load or full throttle (I would not recommend it while parked you might just blow your motor) with cacuum you have little control as to when your secondary opens as it will respond to vacuum changes based on the load placed on your engine, yes it can be adjusted but not as well as with the linkage type.

Most 2002's and some of the first generation 320's had a solex or weber installed and a common performance replacement was upgrading to a weber or if allready with a weber then upgrading to a larger one, most which had weber's used a 32/34 so upgrade was for a 32/34 a 32/36, 36/40 or even a 38/38 also a preferred upgrade was with a dual setup of 40DCOE's side draft or some wild setups I saw were dual down draft.

I used to work alot on these carbs not only on BMW but also used on Fiat, Volvo, Datsun 240Z which used a tripple setup and the Porsche which used 2 three barrel 40, 45, 48 or 50 ida's and it took a lot of patience
to tune and balance them where multiple carbs were used but the sound was unique when you floor them.

I can't speak for weber now but back them I can and they were carbs you could not kill no matter how hard you tried unless you beat them with a hammer, whatever conditions they came to me I could bring them back to like new life.

Back in the days I also saw many custom manifolds and hacked manifolds which would use dual down draft setup, there were two configurations I would run inot many times, even when the first FI models started to show up and people didn't know how to make them perform better they would
cut and weld the FI manifold to hold a single or pair of weber carbs.

Configurations I would see were:
A pair of 32/36 or 36/40 where 2 cyl would run on one carb and the other 2 on the second using the vacuum or linkage secondary type carb.

A pair of 36/36 or 40/40 all opening concurrently 1 barrel per cyl side or down draft.

I think my day and maybe for you also would be to see BMW bring back the 2002 as a retro model but still saying im a 2002.

Xavier