Running both engines off one tank, vapor lock?

CaptBud

Member
Sep 8, 2017
30
Boat Info
1982 searay 360 vanguard
Engines
350 crusaders
So i have a 87' 340 sundancer with 350 crusader 454's.

Currently have both engines running off the port tank so I can burn off old fuel. Both engines run great but once they are nice and warmed up after 30 minutes of driving or so, the starboard engine starts to stumble and fall on its face ONLY WHEN IN GEAR. When I put it back in neutral, it will run fine and I can rev the engine no problem. When I put it in gear, it will usually run a few seconds and then start stumbling again. Always immediately restarts no problem, and when I let it cool down, it runs great again until it gets to operating temp.

Could this be vapor lock related since I am running both engines off the same tank? Is it possible it is not getting enough fuel when in gear because it is having to draw fuel a longer distance and it subsequently gets hotter than the fuel going to the port engine? Or would this be carburetor related?
 
Also, any recommendations for how to check to see if the fuel tank vents are clogged? And how to unplug them if they are clogged?
 
Simple, but, have you changed the fuel filters?
 
Also, any recommendations for how to check to see if the fuel tank vents are clogged? And how to unplug them if they are clogged?

Simple way to tell if the tank vent is clogged is to remove the fuel fill cap when the problem begins. If the problem immediately goes away then you can be sure the tank vent is clogged. BTW what temp is the engine running when the problem starts? Sounds fuel related. Fuel filter, fuel pump, fouled carburetor.
 
Fuel filters are brand new, the only one i have not replaced is the one inside the carbeurator.

The engine is running around 160ish when the problem happens.
 
How close is the inlet hose to the carb to a heat source such as a hose the gets warm.
 

Forum statistics

Threads
112,943
Messages
1,422,709
Members
60,927
Latest member
Jaguar65
Back
Top