Mother's Dual-Fuel Alcohol-Powered Van!

Article Tools

Image Gallery

Print

E-mail

Comments

RSS

Also, a new air/fuel mixture tube was fabricated to replace the original booster distribution jet, which had a restrictive central corridor and did not allow for an air mix. A .128"-inside-diameter brass tube, with the same overall length and outside diameter as the jet, was "slash cut" on one end at an angle of about 10°. Then four .040" holes were cross-drilled approximately 1 inch from this angled outlet end of the pipe. After removing the old jet with a 1/8" drill, the new fuel/air mixing assembly was pressed into place and held fast with a drop of Locktite brand stud mount. Such a combination booster and blending jet serves to atomize the fuel quite effectively.

THE "MIXING" LINK?

Individual throttle control for each carburetor was accomplished, inexpensively, by adapting a Stanley door hinge—and some spare parts—to do "double duty". Its pin was removed, eventually to be replaced with a similar rod about 2" longer, with a 1/16" hole drilled at one end and a knurled head at the other. Then the three "knuckles" of an extra hinge plate were ground down at their shoulders to allow about 1/4" of lateral play in the component once it was positioned "around" the main hinge (see photo).

Next, the triple-knuckled plate from the hinge set was cut into three sections -each having one "loop"-and its two- cylindered mate was permanently fastened to the top of the Y manifold, in an upright position. At this point, three control "arms" were welded onto their respective hinge sections, and holes were drilled through each to accept throttle rods. The linkage was then reassembled, using the long pin as a pivot. (The extra length was added to accommodate the third hinge plate and the spring at one end—held fast with a cotter pin—which lets the whole shebang slide sideways and function without binding.)

Finally, an "anti-dieseling" solenoid from a GM V-8 was installed to automatically move the "master" plate right or left, depending on which carburetor is to be controlled.

Happily, the apparatus functions well in both theory and practice: When the solenoid shaft extends to the left and the accelerator is depressed, the center plate pushes down on the hinge section that activates the alcohol carburetor. At the flip of a switch, the solenoid arm returns to the right—along with the master plate—and the gasoline carb is ready for action.

With this setup, it's not necessary to in corporate individual fuel shut-off valves for the "dormant" carburetor . . . the unused mechanism merely rests in its "idle" position—atomizing no fuel—while the other carb functions normally. (This occurs because such a great volume of air is flowing through the in-use device that there's not sufficient "draw" to pull fuel from the inactive one.) In addition, there's a less obvious benefit to this arrangement. When the engine is idling (in either fuel mode), both the carburetors—which, of course, "draft" equally at idle—can be adjusted to provide nearly any "balance" of gasoline/alcohol ratio desired . . . a feature that allows the engine to operate very smoothly on low-proof ethanol at idle and starting speeds, thanks to the addition of a small petrol "boost".

RSS | Comments | E-mail | Print