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How To Modify Your Weber Carburetor For Rock Crawling

This modification will void any factory warranties. LC Engineering is not responsible for any malfunction, or damage done by the person doing this modification. Perform ONLY at your own risk.

If you are reading this, that means that by now you probably already know that Weber carbs don't like extreme angles. In this case we used a Weber 32/36 DGAV on a 1981 4WD Toyota Pickup Truck. The Weber carbs work great on the 22Rs, they provide a better gas mileage, some performance gains and better drivability under a load than stock. Unfortunately, like we stated before, the Weber carbs really do not like going up steep hills. The main problem causing this is the location of the bowl vent. When the truck tilts back, the fuel spills into the air horn, making the truck stall. To fix this there are three things you need to do. First, make sure the float level is AT MOST spec height, preferably 1-2 mm lower. Second, install a fuel pressure regulator and set it to 3 psi no more.

Third, you need to relocate the fuel bowl vent. This is the hardest part, and the one we're going to focus on. To relocate the bowl vent first remove the top of the carb.

You will notice a couple of rectangles that pass through the top. One of these is the bowl vent. It is the one closest to the fuel inlet, furthest from the choke tower. You will need to plug it. We used JB Weld.

And here it is after the JB weld.

Drill some holes in the port to allow the vapors out. You will be able to see your drill bit through the hole in the end.

Then you will need to vent the vapor somewhere. The fitting in the end is 3/8" inside diameter, so I bought some copper tube from ACE hardware and hammered it in.

Top view.

Now route to the stock carb charcoal canister (under the battery) using 3/8" fuel hose.

You're now complete and ready to hit the trails.