Acedarkman
New member
Hello
I´m new to this forum and I hope that you can help me out!
I have Maxum 2400 SCR (2000) with a 5.0MPI, Bravo 3 (2.0), props 20P. I have since a bought the boat a few years ago thought that the engine is to small and underpowered. I have problems to get the boat up in plane. Max WOT is only 4100 rpm at 30 knots.
My local mechanic told me to investigate the fuel system, since he tinks this could be the problem.
I purschased a fuel pressure gauge and connected it to the shrader valve on the fuel rail today and this are my notes:
Ignition to on, fuelpump starts and builds the pressure up to 40 PSI, when the pump stopps the pressure drops instant to 38 PSI.
After 5 min the pressure has dropped to 34 PSI and after 10 min the pressure is down to 32 PSI.
I turned the ignition back to off and then back to on again, the pressure en 38 PSI efter the pump stopped.
I then started the engine, and come up with the following pressure reading at these rpm:s,
-680-720 rpm, pressure 36 PSI (Idle)
-1000 rpm, pressure 35 PSI
-1700 rpm, pressure 32 PSI
-700-2750 rpm, pressure 30 PSI (fast trottle in nutral)
Fuel filter changed last year, run about 60h sense then, Never gone below half tank.
As far I know the system pressure should be 43 PSI. It should be at constant pressure after the fuel pump has stoped, mine dropps after just a few minutes. The regulator should keep the pressure at 43 PSI regardless of trottle, besides on Idle it should dropp a little bit.
What could be the problem? Regulator? Siphonvalve? Fule line? Filter? What should I start with?
Best regards,
Mikael
Sweden (therefor my bad english
)
I´m new to this forum and I hope that you can help me out!
I have Maxum 2400 SCR (2000) with a 5.0MPI, Bravo 3 (2.0), props 20P. I have since a bought the boat a few years ago thought that the engine is to small and underpowered. I have problems to get the boat up in plane. Max WOT is only 4100 rpm at 30 knots.
My local mechanic told me to investigate the fuel system, since he tinks this could be the problem.
I purschased a fuel pressure gauge and connected it to the shrader valve on the fuel rail today and this are my notes:
Ignition to on, fuelpump starts and builds the pressure up to 40 PSI, when the pump stopps the pressure drops instant to 38 PSI.
After 5 min the pressure has dropped to 34 PSI and after 10 min the pressure is down to 32 PSI.
I turned the ignition back to off and then back to on again, the pressure en 38 PSI efter the pump stopped.
I then started the engine, and come up with the following pressure reading at these rpm:s,
-680-720 rpm, pressure 36 PSI (Idle)
-1000 rpm, pressure 35 PSI
-1700 rpm, pressure 32 PSI
-700-2750 rpm, pressure 30 PSI (fast trottle in nutral)
Fuel filter changed last year, run about 60h sense then, Never gone below half tank.
As far I know the system pressure should be 43 PSI. It should be at constant pressure after the fuel pump has stoped, mine dropps after just a few minutes. The regulator should keep the pressure at 43 PSI regardless of trottle, besides on Idle it should dropp a little bit.
What could be the problem? Regulator? Siphonvalve? Fule line? Filter? What should I start with?
Best regards,
Mikael
Sweden (therefor my bad english
)