HOW TO MAKE VALVE SETTING FOR CAT 3412 - Caterpillar 3412E DITA Marine Propulsion Engine

Click on the link and also on the images tab.

https://www.google.com/search?q=Caterpillar+3412+fuel+injector+return+lines

Service and Repair Manuals, some are free.

https://www.google.com/search?q=caterpillar+3412+service+manual+pdf

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If you're asking for advice on this forum on how to repair a 480VAC system then you are not qualified to work on it.

For your own safety, call a professional.

I suggest you get one of those manuals from www.reliable-store.com instead

Go here. If you can stay on without having to pay a fee. found this helpful answer from technician on JustAnswer com

check with cat dealer service center but to get it running .012" inlet hot and .014" exhaust hot is general engineering specs

Replace the rough in valve

Having looked at the diagrams of the valve I not sure the handle is tight on your stem an is not turning the valve stem.
Look at that and if that's not it I will try to help.

adjust the thermostat setting on your hot water heater. They are located in different configurations. Consult your water heater manual

if you pull the handle off all the way back to the valve body there is a little black stopper around the cartridge body that you can adjust by pulling it out and sliding around the cartridge body this enables people to just turn the handle to one setting and jumpping in to their favorite temperature. in your case it doesn't allow you to have any cold water. so turn it one way see if you get what you want or try the other or some of them you can even just take the darn thing out and not even have to worry about it