I want to thank all you good guys for all the help as I did a rebuild of my 427s the starboard motor started and ran so smooth. The port motor is not getting fuel. I put some gas down the carb and it started right up. The only things I did not replace was the fuel pumps and the port one must have given out over the winter. So I think I’m going to put electric pumps on her. So thanks guys Pics coming soon
Thanks Matt I do have the closed cooling system if I would have thought for one minute the pumps were not good to go I would have replaced them. Never gave me a hint it was going south on me. Going to recheck it by back feeding some fuel into it. The boat has to go in Friday and my dock is just ten minutes away. I may make the trip on just the starboard motor. Thanks again Matt
Matt Cowles said:
Congrats Thomas - glad they’re running. I’d recommend trying to get the mechanicals to work (they’re rebuildable), but if you can’t for some reason, look up my posts about fuel starvation and how I fixed it. I tried several different combinations, and the one I have right now is the ONLY way I’ve been able to a) use marine-rated pumps, b) get appropriate filtration (you need the BIG Racors), and most importantly c) maintain the correct fuel psi to the carbs throughout the entire performance curve.
Happy to talk you through it if you decide to go this route, but again, unless you have a closed cooling system (which makes the mechanicals almost impossible to access), the original system is going to be the most reliable.
Disconnect the line leading to the fuel pump and see if you get gas from the tank to assure that the line is not clogged. It may be a simple fix. Good luck.
Mechanical pumps usually don't die because they were sitting unused for a bit. 90% of the time it will be a shut valve somewhere, clogged fuel filter or loose line allowing vacuum leak.
Thomas, I just replaced both of my mechanical pumps. Not a fun job but it can be done. Also after some research on this site I found that replacing the check valve in the bottom of the carb (supposing you have the Carters) helped the hard start problem that plagues these great engines. If you need the part number quickly it is a Carter M6905 pump. Don't go to your local parts store. Bite the bullet and order them from Jegs.
Having a similar problem with one of my 427's. Can not get gas to input of fuel pump. Determined it must be pick up tube in tank is clogged. Difficult to replace as minimal room between top of tank and deck. Any help will certainly be appreciated. Thank you
If you think your line is clogged, disconnect the supply line at the fuel pump and blow it out with air. An "air blow gun" (trigger controlled attachment for the compressor hose with a tapered rubber tip) can be shoved into the copper fuel line to deliver the air.
This will eliminate clogging as a possible cause. I suspect your root cause is a bad pump. It's a $100 or so part. I would replace it and eliminate it as a suspect.
The fuel pump is a Carter M6905. Amazon for $115 and free shipping (genuine Carter). Also from an auto parts website called JEGS. $110.
The pickup tube in the tank is copper. So rotting is not a factor. Sediment in the bottom of the tank can be a problem. But this most often leads to clogged filters and carbs from the sediment being sucked up into the fuel system.
If the 90 degree fuel line fitting on top of the tank is under the deck (mine are right under a hatch), it's a problem. If you have round, barrel type tanks, one approach might be to pump out as much fuel as possible, loosen the retaining straps that hold the tank in place and then rotate it in the cradle until you have enough clearance.
I'd start with replacing the pump.
Left you a voicemail on your cell.
Thanks guys for all the help I back fead some gas into the pump and it took right off both motors are running awesome