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Voodoo
08-08-2012, 12:42 PM
Folks --

'87 Prostar, 351, Holley 4160

I had lots of fuel system issues this year that I thought were solved but still chasing problems.

Items accomplished, in order:

carb rebuild and fuel filters replaced
new points, cap, condenser -- good timing and dwell
during op check boat died of fuel starvation after 30-45 seconds at 3000 rpm.

Next I:

removed fuel tank, tossed gas, washed out tank, replaced flexible fuel line from tank to fuel pump, replaced fuel pump and cleaned up the fuel tank anti siphon valve, which was clogged.
Took boat back out and it performed flawlessly for 2 hours pulling skiers.

Yesterday:

In preparation for skiing, I started boat to warm it up at the house. Started and ran perfectly. Once idle was stabilized I walked away to assemble the gear. Within three minutes the boat died. It took excessive cranking to get it started and alot of throttle. Engine would run for three seconds at around 2000 rpm and would die. I removed the fuel line to the carb and cranked it over verifying lots of fuel pressure. I am confident that the carb is receiving fuel and that I have spark.

Any ideas?

Thanks,
Voodoo

petermegan
08-08-2012, 07:37 PM
I wonder whether you still have a blocked tank breather, when you disconnected the fuel line it released the suction so you had fuel at the carby. What happens if you start it with you gas lid off maybe. Just an idea. Have fun

j.mccreight@hotmail.com
08-08-2012, 08:51 PM
^ x2 Try running it with out the fuel cap on that would narrow down if the tank is going into a vacuum and causing fuel starvation.

thatsmrmastercraft
08-09-2012, 01:50 AM
Is your electric choke opening up?

TRBenj
08-09-2012, 09:48 AM
Did you run the tank low on gas? If theres crud in your tank (as evidenced by the earlier antisiphon valve clog) then it may have happened again. Its also possible that the crud from that blockage worked its way up to the fuel filter or filter/screen at the carb bowl inlet fitting. It takes very little blockage there (barely noticeable) for it to cause a restriction that will allow the bowl to empty faster than it fills at higher RPM.