Fuel pres. for a 496 mag.
 

What should the fuel pres. be on a 496 mag? What should it be under load?

43-45 psi key on engine not running. Should be stable at idle again between 43-45 psi with vacume line disconnected and plugged. At WOT, it should not drop below 41-43 psi.

Best Regards,
Ray @ Raylar

We have 40 psi.at idle and when you crack the throt. it drpos to 36 psi

You most likely either have one of three scenarios:
1. a problem with a fuel pump-most likely clogged inlet screen.
2. a fuel water seperator filter that is clogging or contaminated.
3. a fuel pressure regulator that is going bad.
Check these items and you will probably find one is the culprit.
good Luck,
Ray @ Raylar

Its my friends boat and he let it sit for a few months. And when he went to run it all the filters were cloggd with black particles. All the fuel lines were decying. Ethenol I guess
So the elec. fuel pump has a inlet screen.
Ill bet its pluged to. Whre is the screen?