Quote Originally Posted by pennyman1 View Post
I know you don't want to believe it, but the mechanical pump will cause the problems you are having, and a reg won't fix it. The Weber is too sensitive to the pulsation of the mechanical pump because of its close proximity to the carb. If your pump is only putting out 3-4 psi, it is almost dead, as a new pump puts out 9-13 PSI. I have run Webers for over 30 years, and installed them on several trucks - if you want the rest of the issues to go away, go with an electric pump - you won't regret it.
Pennyman, I have a factory shop manual for 1989 and it says that the factory pump puts out 2.4-4.2 psi. (Page 14.2 in the factory manual.) However that is equivalent to 20-29 kPa or the metric measurement as you know.

But I think you're right, the proximity to the carb is the problem, not the psi that the stock pump delivers.

I've already bought both the 12-804 and P4070- I am just waiting for my chosen wrench to finish putting up his shop. He's doing the metal building thing- the slab has been poured and he's in the process of getting the building. He already has a lift.

Thanks for all of your inputs guys.

I can't help it these original parts on these things last forever. LOL