I cleaned the pump regularly. You take off the front and there’s a gasket on the back cover that connects to the body. I know what it needs, I haven’t been able to find the parts I need. The sites want a model number and I can even find that on the pump.
There are few gaskets I have not been able to make from stock and even fewer water separators I’ve been able to bypass with non-proprietary parts.
If either or both are not an option, I suggest searching for a forum of like-minded equipment owners and your questions might be easily answered.
Specialty equipment usually breeds necessity and minds come together to solve stubborn manufacturer-created headaches (in said specialty equipment forums).
Specialty equipment is the hardest to maintain/repair. Best of luck, especially if you have no access to a mechanic who might make easy work of this.