95 sport gt-40 Fuel pump question

[dmbump]

I have read many post about warm engines that wont start. I have that problem. When I took off the fuel cap the other day and blew into the take I could get it to start ok. That was about 6:30 in the evening. I was told to check the float valve at the tank, but I don't know were that is. To day I worked on my boat at 1:00pm outdoors and it was very hot. The blowing in the tank trick did not work, the engine would not start. I decided the remove both fuel pumps LP and HP, I don't have the fuel cell. Both pumps were full of fuel. The fuel rail was full of fuel. If the pumps were defective I would assume the pumps would be dry. I am at a lose to what is going on. My boat has run perfect for 15 years until about three weeks ago. It does not make since.

Any thought would be greatly appreciated.

[DanielC]

Fuel pressure is critical. You have to check it. Just because there is some liquid in a fuel rail does not mean the pressure is good.

The GT-40 engine does not have feedback into the engines computer on what the fuel-air ration is. The computer just assumes the fuel pressure is good, and opens the injectors for the proper amount of time, assuming that correct fuel pressure.

Here is how to check the fuel pressure:
http://www.planetnautique.com/vb3/sh...=Fuel+Pressure

You need to download the GT-40 service manual from this site.