Offshoreonly.com - Strange Problem! Any Ideas?

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Quote:

Originally Posted by MILD THUNDER (Post 3842411)

Hey Kris, I think he mentioned it will start and run until the bowls run dry, then no start.

Yes that is correct.

Quote:

Originally Posted by Likefastboats (Post 3842347)

I have a wierd problem restarting my Starboard engine when it's hot. I have 500 HP's with B&M Blowers and upgraded mechanical fuel pumps. Port engine will always refire but the Starboard will not. When cold at the begining of the day both motors fire right up. After running for any length of time when shut done the Starboard motor is starved for fuel and will not start. Here's what I have done so far. New fuel pump, rebuilt carb, new fuel filter, replaced fuel lines and basicaly checked the integrity of the entire fuel system. All this to no avail, same problem still exists. Almost like a vapor lock of some sort. Any ideas on what the problem could be? What should I do next?

This only leaves pickup tube , vent or extreme heat somewhere evaporating fuel . Very hard to diagnose without being there when it happens . Usually with problems like this it's something stupid that's getting overlooked because it's so simple . One of those " good thing it weren't a snake " moments . Good luck and scrutinize it a little harder .

Is the boat rigged with a single PU per engine, or a common PU for both engines?

Have seen Fountains installed fuel line from tank to ball valve collapse internally... only when bilge warmed up. The line looks good but has failed internally.

Ok, Thanks guys for the ideas. I will start in the tank and work my way to the carb again with a fine tooth comb. You're right it is probably something simple that I have overlooked. My buddy is going to come over and help me this weekend. Maybe a new set of eyes will see something I didn't. I'll let you all know what we find. Thanks again.

Make sure you don't have an inner liner of a fuel line collapsing once it warms up. I bought a 98 that had been sitting in someones garage and was like brand new except all the fuel lines were shot. I ended up re-plumbing everything.

The first thing I would do is swap fuel pumps from side to side. It sounds like the fuel in the lines may be leaking back past the pump diaphram.

take a piece of clear hose and a gas can. as soon as motor won't start, swap fuel line ti clear hose and crank motor. if it pulls fuel up and fires motor, it is definately pre-pump problem. if it doesn't pull fuel, it is farther downstream...needless to say, don't go driving the boat around with this jury-rigged system...

Does the fuel level have any effect? As in, full tank/no problem vs 1/2 tank/no start?

Quote:

Originally Posted by Likefastboats (Post 3842393)

Yes loss of fuel presure. Fuel bowls empty. Engine will fire momentarily until fuel bowls empty out. Not ignition, if you pour a little fuel down the carb it will fired for a moment. Definatly a fuel problem. Headers are Stellings green.

in the op,you stated that when the engine is hot it wont start,now you say it wll start and run until the fuel bowls run dry,2 different scenarios,please clarify exactly what happens when the engine gets hot after a hard run.