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lazy fuel pump?

G

glorious_one

New member
After about a week of inactivity, my 1987 port 454 Crusader engine will not start due to lack of fuel in carb. It seems that the fuel is siphoning back into fuel tank. It will start after a few sips of gasoline down the carb's throat and run fine even a day or so later. Rochester Carb is recently rebuilt. Lazy fuel pump?
 
not likely, as this has become a very common issue on many boats recently. It is due to the fuel just evaporating out of the bowl over the course of a week of inactivity, especially when the summertime warm spell sets in.

Better to add those sips into the bowl vent vs pouring them down the carb's throat. Not only will it provide the desired liquid at the needed spots, but the internals and the oil will be better off, too.
 
Fought that battle for years, wearing out starters and ring gears, before adding an electric boost pump to fill the carbs. A check valve at each carb prevents back flow when the motors are running. One pump, running off the gen-set fuel line, does the trick.

Works slick!

Jeff
 
Actually, I have had the same situation going on the 4th year of owning this boat. Edelbrock 1409's and if it sits more than 4 days, it takes about 15-20 seconds before starting and dying. The she is great for anywhere from a day to 4 days. Over 6 days and it is the same thing all over again.

I have seen a few pictures of Jeffs installation and it is slick !
 
thank you very much for the input. Information sounds very reasonable but why does it only happen to the port engine and never my starboard. also, jeff, if that drawing is still available i would appreciate a link to that very much.
 
My theory says you moor in a slip and your compass indicates anywhere from SW to N. So the port side sees most of the solar heat load from the sun.
 
Here's what the system looks like. One electric pump fills both carbs. The round aluminum object in the system is a check valve to prevent backflow as the motor is running.

Jeff
 

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Ill-Eagle is a sick bird!

All connections are supposed to be flared, but 1/8 inch tubing is a bit hard to flare (and doesn't leak like larger compression fittings might. Note that most oil pressure (up to 80 or 90 psi) gage fittings are also 1/8 " compression and rarely leak when tightened properly.) I check ALL fuel connections regularly,just to be sure.

Jeff
 
Jeff, I was looking at this photo the last time you had it posted and I found it interesting then and now I have a few questions....this is all theory on my part so if you can confirm it, I would like to give it a try

I believe the line coming in to the carb from the upper right corner is the main fuel line and has an in-line filter installed in between the rubber fuel line

The "T" takes that rubber line and feeds the main fuel input to the carb

The CHECK VALVE is on the lower side of the "T" and is connected to your thinner fuel line which is coming from a momentary on electric fuel pump fed from the gen-set fuel line?

The "T" is connected to the carb fuel "IN" using a short nipple?

Thanks AL
 
Correct. The main fuel pump would push fuel backwards without the check valve. System works excellent, but I still need to roll the motors over FIRST to make sure thre's no water in them. Every inboard boater should get in the habit of doing this regardless of the age of your equipment--especially you salt water boaters.

Jeff
 
Chuck:

You just have to remember a couple things when selecting connections:

1) EVERY fuel pressure gauge instruction sheet I've ever seen warns you to mount the gauge OUTSIDE of the passenger compartment due to the hazards of a parted connections, and

2) Gasoline isn't oil and boats aren't cars.

I'd be inclined to use AN fittings if one has difficulty making flares.
 
Agreed, but 1/8 inch is hard as hell to flare! Pressure wise, the connection is good for over a 1,000 psi due to its small diameter.

Jeff
 
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