Cold start, long crank times Where's the gas?

[JDW]

I have a 1994 220 Overnighter 7.4 motor with a Weber carburetor, Bravo III
If this boat sits on the trailer for more than one day I have to crank the motor for a long time to get fuel into the carburetor so it will fire. Once the engine is running it starts fine anytime the rest of the day and maybe the next day. Two days of sitting and it takes a long time to start again.
Is there a check valve somewhere in the fuel line after the fuel tank that is allowing the fuel to drain back down into the tank? I don't see one after the fuel filter.
Hope someone has an answer for this. JD

 

[relentless1996]

I have the same problem. I hope someone has the answer

 

[Dick270da]

Not familiar with any type of check valve but for a cold start problem I'd check the operation of the choke. When I start mine cold I first pump the throttle about 3 times (depress the release button on the throttle so you're not shifting) to activate the accelerator pump and squirt some gas in the carb. Have someone pump the throttle while you look down the carb throat to ensure it's working. Obviously don't crank the engine while doing this. Good luck!

 

[mysticowner]

Sounds like your fuel pump is shot. It's letting the fuel pass back
down the line. This is common in cars. Your fuel pump is no different.

 

[PlayDate]

If this problem is new, then as others have said your fuel pump probably is the issue. A simple pressure test will tell you if the pump is at fault.

More likely: it is the result of the Weber and Rochester carbs tendency to leak down when not in use and subsequently require extended cranking for the fuel pump to replenish the fuel. If this been happening as long as you have owned the boat then you have a couple of solutions both of which work well. First, you can ditch the Weber for a Marine Holley which will solve the problem. Or you can put an Marine electric fuel pump (with a oil pressure safety switch) in with a "prime" switch bypass at the helm allowing you to run the pump for 10 seconds or so before you pump the throttle and turn the key.

-John

 

[Phlorida]

I have a 1995 5.7L with a Rochester Quadrajet carburetor that has the identical symptoms. I have always attributed the issue to the accelerator pump in the carburetor rather than the fuel pump. When the engine is cold I pump the throttle five times as previously described and the engine always starts on the second or third revolution of the starter. Since that effectively solves the problem I have never looked into a more permanent solution.