Weber 38 DGAS on B2000

In an effort to solve my fuel issues once and for all we put a Weber 38 DGAS on my 87 B2000 this morning but have a couple questions. My weber has 3 vacuum ports, 2 big and one small. One of the big ones seems to do nothing and have no effect plugged or unplugged. The other one seems to have a ton of suction and with it unplugged idles very rough. And the little one seems to do nothing also.

My question is where do these get hooked?

And also, the carb seems to have a whistle coming from the inside of it. Is this normal or something?

If I had to guess,

The two big ones are not vacuum at all. They are the water inlet and outlet for the water choke. A big hint is that you called it a DGAS, the A stands for "auga" which is spanish for water, and the third letter is the type of choke. A DGES has an electric choke, the DGS has a manual choke (no letter, no automatic choke!)

The little one is for the vacuum line to the distributor advance can.

If in fact my assumption is right, you need to hook up a water line to the choke, you just cut a small one and run each side of the cut to each port on the choke.

The whistle is likely an air leak at the carb base. Most people tighten the hold down nuts too much and it warps the carb base causing a leak. Other people dont double nut the mounting studs and tighten them down before installing the carb, and that lets the vibration back the studs out again causing an intake leak. Make sure you use the paper gaskets between the adapter pieces. I usually use a skim coat of RTV on the gaskets, a big no-no from Weber. But likely the reason they say no is because the throttle butterflies open below the carb, and RTV buildup around the barrel can make the throttle stick open and kill you. Additionally, people tend to rely on RTV INSTEAD of a gasket, which can be very bad in a gasoline environment as well. Again, I just take the paper gasket and BARELY wipe on some RTV to help make a seal, I had a warped base on a 32/36 on a BMW 2002 once and RTV fixed it slick as snot.

Hmmm, this one also has an electric choke. Well, at least has the tab to connect a wire to. And is it really possible that the big one isn't a vacuum line if it effects the idle so greatly? Placing a finger over it almost hurts cause of the suction it has. If it was for water would it really need to suck that hard and not blow out the other port at all?

pictures would help. Weber DG carbs usually only have the one little vacuum line.

That whistle could be related to the suction...

And there is sometimes an "anti-diesel" solenoid that is installed on the choke side of the carb, it has a tab connector and is there to keep carb vacuum from drawing more fuel after shutting the engine off.

Yeah, I just finally found a parts breakdown of the carb and the water choke in the diagram isn't anything like what I have. I believe I do have an electric choke. Will have to look more closely tommorrow and see about getting a pic also. I appreciate your assistance and will get more info.

THanks.

Don't know if this helps ya any but here are some pics I snapped tonight. Double checked and it does say 38 DGAS.

The blue arrow points to the big vacuum line that has a ton of suction. It has a plug over it.

sorry, I need a better picture. That picture doesnt show anything but the plug.

If you look at this picture of a 38 DGES, there is nothing even on the casting on that side.

Are you certain you are not mistaking the big vacuum line for the PCV or the brake booster that comes off the MANIFOLD and not the carb? They are also around that area.

oh and that barbed brass fitting is a fuel return from the float bowl, not a vacuum line.

You're kidding right? Pictures are about as clear as they get.

Under the vacuum plug that is pointed out with a big blue arrow, is another barbed brass fitting identical to the one that you claim is the fuel return. It is coming off the carb and not the manifold where the brake booster is connected.

I'm not sure what kind of pictures you want to help tell me what these mystery "vacuum" lines are. I'm not exactly entertained by the notion of disassembling the carb to take pics of 2 fittings that are pretty obvious in the above pics.

Sorry to hear, good luck to you!