Close call yesterday!!
 

We were out in the Velocity cruising about 75 and she started to lay down, quick glance at the gauges and everything looked fine. Looked again and saw fuel pressure dropping.
Slowed down and could smell fuel. stopped and opened hatch to see 3 gallons of fuel in the bilge!!
Quick look and found that an AN fuel fitting broke off the fuel head!!
I am still sick to my stomach thinking about what could of happened to us if she would of lit on fire.
I have been doing fuel lines for 35 years and i have NEVER seen this happen before. It was a sniper fitting.
I happen to have a manual bilge pump to get the fuel out and a towel to clean the rest.
I was able to get the broken fitting out of the fuel head and move some things around to get fuel hooked up again and got to the dock safe.
SCARY!!

What fuel head? Is it an Not to AN fitting? Need pics!

My fuel pressure gauge is in the engine bay at the rail, but maybe I should find some space on the dash...

It is the factory murcury mechanical lift pump on a sci 575. I ran a An fitting from fuel pump up to the factory fuel head. The factory line was very restrictive. It was just a short 12 inch hose with a 90 degree on each end. Low pressure 8 psi. The straight fitting 1/4 pipe to -8 an is what broke off. It was not under stress or rubbing on anything. Just crazy strange. Must of been vibration or it was just a bad fitting.

Glad you found leak before it got ugly. BTW How did the prop test go?

Harmonics due to vibration can be destructive. Prev owner of my Fountain said he was breaking alternator brackets left and right for no apparent reason. He added a stiff spring to each bracket to break-up the harmonics and never broke another bracket again. He also had a rigid 1-piece fuel feed line for the Holley double pumpers crack soon after installing it. It's now a 2-piece feed line assy and 10+ years old.

Dash mounted fuel press gauges are a good thing. Been thinking abt adding an instrument pod for fuel press and wide-band O2 gauges.

That's the strange part, this boat and drive engine combo is VERY smooth. At any speed I feel zero vibration.

hey man, good prop. Feels like it has less lift than my other bravo prop and the velocity likes that. I noticed the barrel is shorter on it. Boat will do 90 with that prop you sold me.

Same here. Runs like a sewing machine.

You have my sympathies. Experienced a similarly scary event recently it stays with you for a bit.

I have 2 brushless bilge fans that move a ton of air.
maybe that was just enough to help keep fumes down. Solid tight electrical connections and good plug wires.
Makes you realize how important this stuff is. I run with fans on all the time to help move air through the engine bay.

Having that much fuel as OP epxailed for his experience may have had a very rich mixture in the bilge area. Rich mixtures have a harder time igniting.

Blower fans would both pump out gas vapours and introduce oxygen, lowering the rich mixture to a more explosive and easier to ignite mixture.

Just keep that in mind.

OP with the manual bilge pump: nice peice of kit to have on board.

The hand pump saved the day, some fuel line and hose clamps are also a good thing to throw in the spare parts bag.

It`s 2025 , no pics?

Honestly I was so panicked to get it fixed pics were last thing on my mind. The broken fitting is 200ft below water lol. It was 95 degrees and I actually got heat stroke fixing the thing. Yesterday I had to leave work early felt so crappy. Better today. Massive water and electorate fixed me up. I'm considering changing my fittings to steel. It was a 1 in million thing though I'd bet.

the dude is worried about setting off a bomb and you want pics 😂😂😂

Just wanted a picture of the broken part, wanted to see where and how .. so sorry, I didn`t know it fixed itself before pics could be taken.

I agree...mechanism of failure would be great to have documented.

When you're in the Matrix...difficult to focus on anything but the immediate.

Any fitting that has dynamic loading would be suspect over time.

Stainless AN fittings, aseembled not pressed, re-usable.

304 stainless, but better than alum and steel for corrosion.

I've seen alum AN fittings oxidize and powder away on the inside.

https://www.anhosefittings.com/ptfe-...ing-4an-1.html

Is there a better source that's 316L? Better pricing?