Dual gas and propane system, aft tank that used to be gas is now propane, when switched from front tank to aft tank then you have to switch of another switch that turns off the electric fuel pump and propane does not work. Hope that makes sense. Any information regarding this problem appreciated.

Everything seems to work but does not run on propane.

 

Could be the regulator valve, how does this work in a propane system? Newbie here to this system.

 

You should have an electric solenoid that controls the flow of propane. It sounds like it is either not getting electricity or it may be corroded and stuck. Is there a filter in the line? It may be plugged. Is there propane in the tank?

 

Yes there is propane, just put in tank. The solenoid seems to be working. What do you mean by filter in the line? Where would this filter be? I have owned vehicle for a few years and this is the first time I am using the propane system on it.

 

The system 'should' have a filter in the propane line, usually just in front of the electric propane solenoid. Mine is a metal can about the size of a beer can and about half as long. Try this: turn off the propane line at the tank,take the line off the solenoid and open the valve just a little bit. Listen and see if propane flows. DO THIS OUTSIDE AWAY, FROM ANY SOURCE OF IGNITION. If so, reassemble the line to the valve. My regulator has a button in the center. If yours does, unhook the line that goes to the carb. This is a large line, about 1 in. With the ignition 'on', and the propane selector switch 'on', press the button. You should hear the propane hiss in the hose. This won't be a loud hiss as the propane here is regulated to ounces of pressure. If propane is flowing here the problem is in the carb. There is a diaphram in the carb that is prone to breaking. If it is broken or leaking the carb will not work. The carb depends on vacumn pulling on the diaphram to open the valve to flow the propane into the carb. It is pretty simple to replace. The regulator has a diaphram in it also but they generally do not give a lot of trouble. There should be an electric fuel solenoid in you gasoline line and it should close or shut off the gasoline when the propane valve is open. You cannot run both gasoline and propane at the same time. This information is for the IMCO brand of system as this is the only one I have had any experience working with. Basically you just check for fuel at each component until you find the one that doesn't pass it on and repair it. Maybe this will help youget going.