Unfortunately, the original MD90B manual is out of print. But the MD90C,( which is available from any dealer), manual has the same codes. The schaeder valves are metric; you can get an expensive gauge set from Tohatsu, or use a tire gauge.
I assume your model is MD90B.
What in the heck is a fuel vacuum regulator?
What manual are you using?
7000 and battery is a FFP issue. Could be a severed line or a pump problem. That info is right in the Factory service manual.
What are your air and fuel rail pressures?
The electric pumps are pretty reliable. MSRP around $400. I changed one in all my years working on these. There are fewer than 10 units in stock at Tohatsu America.
Flooding has nothing to do with no spark. The check valve is to keep the accelerator pump full, so if it leaked, the worst would be no fuel from the accelerator pump. Re check your needle valve and float.
Of course everything is in the Factory service manual, available from any dealer. An analog ohm meter will be your friend. How do you know it does not have spark?
