Starving 502
#1
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Starving 502
I have a pair of 1996 502's with MPI in a 1996 Powerplay.. The starboard engine has begun starving for fuel anywhere above 3000 rpm. I was pretty low on fuel so I went to my neighborhood gas station and helped the oil companies by taking 100 gallons of their hands (ouch !!) I also replaced the water separators. Neither helped. The port engine is running fine. I did notice that the fuel separator filter canister was only about 1/2 full. I'm thinking either:
Fuel pump
pressure regulator
crap in the tank pick up tube (seperate pick up from the port engine)
Both engines idle fine. Do you guys have any other ideas? All comments are appreciated. Thank you in advance.
Mike
Fuel pump
pressure regulator
crap in the tank pick up tube (seperate pick up from the port engine)
Both engines idle fine. Do you guys have any other ideas? All comments are appreciated. Thank you in advance.
Mike
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Re: Starving 502
first and most obvious question is " whats the fuel pressure ?" when it starves. IF you are correct, the fuel press gage will go to zero or there abouts ... if the gage still reads bet 35 and 45 and it " starves" then its not the fuel pump or delivery system...
if the gage is zero then sounds like exactly what you say... either the hi press pump not gettin g the fuel from the tank or the hi press pump bad in its own right. easy test is to rig switch the lines from the tanks... if the prob stays the same then its not the pick up or that system... if the prob goes to the other motror.. then you know... also do same test w/ pumps... just swap them and see if prob moves with the pump or stays w/ the motor... either way you have your ans in less than 30 mins.
if the gage is zero then sounds like exactly what you say... either the hi press pump not gettin g the fuel from the tank or the hi press pump bad in its own right. easy test is to rig switch the lines from the tanks... if the prob stays the same then its not the pick up or that system... if the prob goes to the other motror.. then you know... also do same test w/ pumps... just swap them and see if prob moves with the pump or stays w/ the motor... either way you have your ans in less than 30 mins.
#3
Re: Starving 502
Do you have the VST or Cool Fuel system? I had the VST system and when the screen filter for the electric pump in the vapor tank would load up, the engine would stumble around 3500rpm. I cleaned the screen and installed the Racor Separator/Filter in place of the Merc filter and solved the problem. The Racor filter has a water drain and will trap the small particulate that will bypass the Merc filter and clog the screen in the VST.