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Rebuilding and adjusting a Keihin 3bbl carburetor.
I have a 1980 Civic wagon that I absolutely love driving. When it's actually running. A few years ago, my mechanic (the only guy I know in the area who can fix my carburetor) retired. I decided if I want to keep driving my car, I'm going to have to learn all about this weird carburetor and maintain it myself. Here's a picture of me and the "SuperHonda" (as my college friends dubbed it) back when we both looked way better:
For those of you who aren't familiar, for a few years, Honda made this weird engine called a conceptually very complicated crazy engine, or CVCC for short. It has this pre-fire chamber that the spark plug sparks in, instead of doing it directly into the cylinder. Here's a picture:
Compound Vortex Controlled Combustion
The pre-fire chamber needs a separate air/fuel mixture than the cylinder, so someone (I guess it was Keihin the maker) came up with the 3 barrel design. The primary and secondary work just like a 2bbl, and the aux. barrel, number 3, feeds a separate mixture to the pre-fire chamber. This allows the mixture in the cylinder to be extra thin. Along with a crap-load of other stuff that breaks a lot, this made the engine super lean and clean running. At least for its time. I still occasionally get 36 mpg. Better than some modern hybrids.
Anyway, I thought I'd share my learning adventure with you in case there's still someone out there who still loves their CVCC engine and 3bbl carburetor. I have a whole series of videos to share, but I'll start with just the first one, so this post doesn't get ridiculously long.
Re: Rebuilding and adjusting a Keihin 3bbl carburetor.
The aux. barrel feeds the pre-fire chamber in the engine. The pre-fire chamber has the spark plug instead of lighting the fuel in the cylinder directly. It's all part of the CVCC engine setup. I've never installed a Weber conversion, but I've heard that there is supposed to be an adapter that sends fuel from the primary barrel to both the cylinder and the pre-fire chamber. But like I said, I've never seen one. I'm one of the few odd folk who prefers to keep the stock carburetor.
Re: Rebuilding and adjusting a Keihin 3bbl carburetor.
Finally managed to pull the carb, the rubber insulator is slightly warp, that explains the slight leak while warming up and the loss of idle when warming up
Thinking of resealing with the right stuff and seal all for the gasoline soaked area
