fuel leak when trailering

[oldrudedude]

I recently aquired this 1971 evinrude 50. I have dismantled and cleaned the carbs (although they appeared to be clean as a whistle), set the timing and adjusted the linkage. It now runs as well as I can expect, BUT:

I trailer the boat with engine tilted up. After trailering I notice that fuel has leaked out the carbs into the engine housing and onto the transom of the boat. This is with the fuel line from the tank disconnected. I have previously replaced all engine fuel lines and clamped with hose clamps.

Does this mean my carb float needles need some work or is this kind of leakage to be expected when trailering in the tilted up position?

 

[bgbass.1]

Re: fuel leak when trailering

you will get some out when tilted just unplug fuel line and let run out of gas

 

[oldrudedude]

Re: fuel leak when trailering

Thanks. I assume you mean when the boat is still in the water.

 

[tashasdaddy]

Re: fuel leak when trailering

whenever you tilt the motor, throws the carbs out of level, you get a leakage with the pressure from fuel tank, and sun expanding the gas.

 

[tcindie]

Re: fuel leak when trailering

Thanks. I assume you mean when the boat is still in the water.

When you pull up to the ramp to unload, pull the fuel line. So yes, still in the water.

 

[larky]

Re: fuel leak when trailering

at the bottom of the air silencer, on the port side, there is a hose that is supposed to drain any leakage down into the exhuast ( or maybe the crankcase). any way, check to see that the hose is in place and not roted in two. the air silencer should catch any leakage, and when the motor is tipped down to be used then the excess gas will drain out.

 

[BMOLCHANY]

Re: fuel leak when trailering

I have a fuel line shut off valve on the line just downstream from the bulb that I turn off when I am just pulling into dock. As I tie off I let the engine run and it will within a few min run out of gas. This way I do not leave any gas in the motor.

 

[Dennisanoka]

Re: fuel leak when trailering

The experts here will caution against ever running a 2 cycle engine until it runs out of fuel. Let's just think about it for a moment, no fuel-no lubricant. Is there a huge risk? Maybe not, but it's not one that is necessary. Additionally multi cylinder engines may not all run dry simultaneously, therefore increasing the risk. I never do it and when one tank is getting real low I switch over before it's gone.

If the air silencer leaks fuel out the edges it's because the gasket needs replacement.

 

[rjezuit]

Re: fuel leak when trailering

On a multi carb engine you are correct. On a single carb, no fuel=no lube but also no run. There is sufficient residual fuel/lube in the system for the seconds it takes until it stalls. Rick

 

[CATransplant]

Re: fuel leak when trailering

Again, for single-carb engines, what I do is disconnect the fuel line at the dock, and idle the engine with my thumb on the kill switch. The instant the idle starts to speed up from being lean, I kill the engine. I've dont that for many years, with no ill effects.

 

[oldrudedude]

Re: fuel leak when trailering

Thanks all for the good advice.

I had removed the air silencer gasket because it had been mangled by the PO. I didn't think it served much of a purpose because the air isn't filtered. Now I understand why it was there. Guess I will make a replacement. The drain hose is intact.

I will run the engine, with fuel hose removed, until it begins to stumble, then turn it off. That should use sufficient fuel to prevent leaking while trailering.

 

[KenMcG]

Re: fuel leak when trailering

I'm going to guess that you have a float and float needle stuck open. I don't know how many carbs your engine has, but I would bet that while you are motoring across the lake, it is dumping fuel then. You only see it when you tilt the motor for the drive home. If this is true, just clean the float and needle and seating port with carb cleaner spray. Also make sure that the float floats in a cup of water. I just had a Ford 8N tractor dumping fuel on the ground. I took the carb apart, cleaned, tested the float, put back together, and it is OK now and I never found a problem.

 

[KenMcG]

Re: fuel leak when trailering

You also mentioned that you have the engine running as well as can be expected. You may be dumping excess fuel into the intake without knowing it if you have a float needle stuck open. It could be too small of an amount of fuel to visibly see. Symptoms are symptoms of other symptoms.