1988 300 Weekender Fuel tanks

[JAC RMNF]

Finally got the old boat patched up enough to do a test run...
Ran well until port tank went dry, switched to starboard tank and ran for 1 minute and died.

Can anyone advise of there is a one way valve in the fuel lines? I can pull a little fuel through but cannot push air backwards through the line by blowing it.

 

[MasterFab]

There is a check valve on each tank, at the aft top of the tank, inline with the shut-off valve, and before the filters. On an older boat such as yours, they do tend to accumulate debris over time, and can partially clog and cease to function as intended. Removal is quite simple - just disconnect the fuel lines and un-thread them. Replacements are easy to source.

Dale

 

[dwna1a]

You may also want to check the fuel tanks vents on the hull. Spiders love to build nests and close them off

 

[JAC RMNF]

Got the fuel problem fixed. Ow engines won't run over 2500 rpm without backfiring. Timing is checked and exact. Brand-new plugs, wires, and coil. Has to be the Thunderbolt 4 ignition. Changed out control modules with a proven engine and no change. Any thoughts? Idles great but will not pull under any load.

 

[dlvwill]

You may not be all the way there on your fuel supply issue. Could be running out of fuel and you're getting lean backfire.

 

[dwna1a]

First go the cheaper route. Have you changed the pickup and rotor? How are the wires? When was the carb last rebuilt? Have you drained and replaced the fuel separator filter also the filters at the engine and the one in the carb?

Check the gaskets at the fuel separater. If they were put in wrong it will starve the engine.

 

[JAC RMNF]

Turned out to be a bad ignition control module in distributor. Replaced and now runs great