Gas leak scare (and simple fix) - EFI owners

[C_Spray]

I pulled into a marina on Sunday, and one engine would not idle correctly. The engine smelled rich, so after we tied up, I opened the hatch and went to fire it up. BIG MISTAKE. I should have gone in and sniffed first. As soon as I turned the key and the pumps came on, there was a small, fine-spray geyser of gasoline spraying straight up! Fortunately, it did not ignite. I got everyone off the boat, got out the handheld extiguisher, turned on the blowers and closed the cabin door. There was several ounces of gas in the intake manifold and a film of gas residue all over the top of the engine. Bit by bit we got it evacuated and all cleaned up, and then went looking for the leak.

The Schrader valve on the fuel rail (used by mechanics to check the fuel pressure) was the culprit. It was leaking, and the plastic cap on it was no match for the 50 psi the pumps were putting out. We replaced the valve with a small fuel pressure gauge that a friend had, and counted our lucky stars.

Here's the kicker: I checked out the offending Schrader valve this morning, and it turns out the actual valve core had backed out about half a turn! This engine had about 440 hours on it.

I am going to re-install the valve, check to make sure the one on the other engine is tight, and install METAL valve caps on both valves. I was considering simply replacing the valve with a 1/8 npt port plug, but with my luck, I will need to check fuel pressure the next time I run.

All EFI engine owners should do themselves a favor: Go out and buy or borrow a valve core tool, check the Schrader valve(s) on your engine's fuel rails, and make sure that you have metal valve caps on them. You can get metal tire valve caps at most car parts stores.

I'm still trying to determine why I never heard the gas fume detector in the bilge go off. (It was working a last weekend when we refueled in a headwind.) It might have been the wind and engine noise while we were running, but it was silent at the docks. Time to get that checked for sure!

I feel very lucky...

[Chris]

I still can't believe that federal law doesn't require every gas-fuelled engine in an enclosed compartment to have a fume sniffer. I've seen the end result a couple of times- all resulted in fatalities.

[Wobble]

I still can't believe that federal law doesn't require every gas-fuelled engine in an enclosed compartment to have a fume sniffer. I've seen the end result a couple of times- all resulted in fatalities.

Totally agree, mine is so sensitive that it detected an exhaust manifold gasket leak before I could hear it ticking.

Getting a hard alarm when you are motoring across the bay is disconcerting but potentially a life saver.

The better models turn on the fans automatically.

I wouldnt own a boat without one.

[cigdaze]

Got lucky, Chuck. Thank goodness there was nothing more than a scare. Good heads-up to all of us. Thanks, good luck!

[Wobble]

This is the one I buy http://www.westmarine.com/webapp/wcs...tial/0/0?N=377 710&Ne=0&Ntt=FUME DETECTOR&Ntk=Primary Search&Ntx=mode matchallpartial&Nao=0&Ns=0&keyword=FUME DETECTOR&isLTokenURL=true&storeNum=8&subdeptNum=12411&classNum=13002

[Tom A.]

Thank god everything turned out ok!

[C_Spray]

This is the one I buy...

Yep. That's the one Formula installed at the factory. Like I said, I know that it worked last week, since it went off while I was fueling, and the wind carried the fumes into the bilge. I wonder if it was going off while I was running, but "timed out" by the time we stopped? It's mounted low, down by my right knee, so I can't see the indicator light. Might be time to relocate it...

[C_Spray]

Just read on the Formula web site that you can check the gas fume sensor in your bilge by holding an (unlit!!) butane lighter with the button depressed in front of the sensor. Handy tip...

[txriverrat2001]

Totally agree, mine is so sensitive that it detected an exhaust manifold gasket leak before I could hear it ticking.

Getting a hard alarm when you are motoring across the bay is disconcerting but potentially a life saver.

The better models turn on the fans automatically.

I wouldnt own a boat without one.

Or a Carbon Monoxide detector if you have a genset .........

[Perlmudder]

WOW! Question, what does this valve look like and will there be on a 5.0efi volvo penta?

[txriverrat2001]

WOW! Question, what does this valve look like and will there be on a 5.0efi volvo penta?

Should be # 18 in the attached diagram -

[Prostock85]

Yep. That's the one Formula installed at the factory. Like I said, I know that it worked last week, since it went off while I was fueling, and the wind carried the fumes into the bilge. I wonder if it was going off while I was running, but "timed out" by the time we stopped? It's mounted low, down by my right knee, so I can't see the indicator light. Might be time to relocate it...

The company I use has units for dual helm, basically a mirror of what the lower unit is but made to go in a standard gauge hole. I'm sure you current one has that option (on my phone so I never clicked the link you provided)

[R'Addiction]

Scary moments that day! I think it was the run from the Bohemia

[C_Spray]

Scary moments that day! I think it was the run from the Bohemia

What? We never exceeded 74 mph nor an altitude of more than 6 feet....

[JupiterSunsation]

WOW! Question, what does this valve look like and will there be on a 5.0efi volvo penta?

A schrader valve is the same one you put air into for your tires so that is what they look like. On my 6.2's it is below the air cleaner cover on the right side of the motor.