Have a Clark CF40B With the Zenith Water jacket style Vaporizor and what I'm told is called the C Regulator right after it,it has the two diaphragms that you can unscrew from the unit.....Customer says it starts hard when cold.....it has a new ignition Sytem on it and I replaced the Vaporizor recently but not this C regulator as my shop can't find one for less than 5-600$$$$..... What is a good way to check this reg and what is the adjustment procedure for the screw that is in the end of it? What fuel PSI should I be getting out of it To the zenith air fuel mixer(is a street elbow style mixer,no Diaphrams in it)....