Any idea how high the pressure is on the return side?

I've noticed some slight variations in fuel pressure from time to time. This time out is was about about 7 to 10 psi variations in the gauge. Really caught my attention. This setup worked fine untill last Friday.

I don't know what the return line pressure is at.

Been crawling aroung in the bilge this evening. Don't see anything visually. It would be nice if an air leak would translate into a gas leak but it doesn't always work that way. I'm getting new filters tomorrow, but I'll have to wait to the weekend to check the plumbing. I don't want to pull all the lines while the boat is inside the garage.

When running returns on dual tank setups, imco makes a nice switching valve for EFI setups for dual tanks. Supervalve six port. Works great!

http://www.imcomarine.com/pages/tanks.html

Just Finished Fixing A Fuel Pressure Problem Where It Was Sucking Air In The Gasket On The Fuel Water Seperator. The Filter Did Not Leak A Drop. Check Gaskets On That.

Hopefully it's that simple. The filter will be swapped out tomorrow.