Small Engines (Lawn Mowers, etc.): Pulse style fuel pumps, ez go golf carts, vacuum gauge

Question
I have a question on pulse style fuel pumps- they have one hose hooked to the crankcase and the other hoses are suction and discharge. How does one diagnose these accurately? I have an engine that seems to starve for fuel under load, the carb is clean, the filter(on suction side) is clean. It does start, but bogs under load. Is there a fuel pressure spec or suction spec for these? It is easy enough to tee in a fitting and then a pressure or vacuum gauge and then watch. I am asking a kind of generic question, but I have seen these used on everything from Deere riders, Kohler 2 cylinders and even ez go golf carts. Thank You

Answer
There are not a lot of spec out there but below is a link that may help.


http://www.briggsandstratton.com/engines/support/frequently-asked-questions/Serv

Kohler provides some specs...see chapter 5.

http://www.kohlerengines.com/onlinecatalog/pdf/SM_CH18_CH750_1_11.pdf

Is the fuel tank venting?  I have come across a couple of bad gas caps but this is pretty rare.

Let me know if the links help.

Eric