Sorry, I got into panics at work today. Below is what I wrote up a long time ago. It keeps me from having to type as much.
The factory sealed the end carburetor butterflies with something called DAG213. After rebuilding the carburetors, this wears off. I tried hand treating the butterflies with this treatment, and I was not successful. With this as a given, all you can do is get the best mechanical seal possible. First the throttle body has to be separated from the rest of the carb. With the butterflies closed, hold the throttle body between your eyes and a bright light. Note the light leakage past the butterflies. If you don't see any, be thankful and don't touch them. Otherwise, now remove both butterflies. Re-install the one closest to the linkage that is controlling these butterflies, but without the screws. Note that it inserts from the top with the “buttons” keeping the butterfly from dropping through the shaft. Continually “massage” how this butterfly fits until you get minimum light leakage. Do this with each butterfly, then with both of them to assure you get the best butterfly in each bore. You might have to install the screws to help hold the position during these trials. Now do it over again for the final installation, assuring the screws are tight this time and that you achieve a result as good as your trials. Note that if the screws are not tight they like to fall into the engine later on. A small dab of Loc Tite will help. It is a tedious process, but anything less will be a compromise towards more leakage. It will not be perfect, but it will be better than the factory (without their sealer) and it work well enough so as not to be a problem. I believe you will see a noticeable difference in the light leak when you are done.
|