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Fuel leaking - Mercruiser quick disconnect fuel rail fitting

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I’ve got fuel dribbling from this fuel line where it goes into what looks like a fuel rail quick disconnect adapter. It is leaking from the brass fitting where it connects to the silver fitting.

Is this rebuildable once disconnected? Or do I need a new fuel line?

Engine is 2004 6.2 MX. I tried a different prop to no avail.

@Shlbyntro any pro tips?
 
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Runs2rch

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View attachment 1216509

I’ve got fuel dribbling from this fuel line where it goes into what looks like a fuel rail quick disconnect adapter. It is leaking from the brass fitting where it connects to the silver fitting.

Is this rebuildable once disconnected? Or do I need a new fuel line?

Engine is 2004 6.2 MX. I tried a different prop to no avail.

@Shlbyntro any pro tips?
Disconnect it. Should be o rings in the rail side iirr?
 

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Disconnect it. Should be o rings in the rail side iirr?

I’m hoping so. I haven’t looked at an exploded diagram yet. Trying to find it for my model this morning.
 

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2005 or so 6.2 right?
Yes 0w059999 and under.

I don’t see the line or fitting in the Mercruiser catalog on their website.

There is a fuel rail plug on the intake manifold and fuel rail page, and the fuel pump page references bulk fuel line from the regulator to the intake manifold.
 

Runs2rch

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This is what I have. It is listed under 350 MPI on the CP website
7995F5FB-C08A-4871-B0B7-7E2CCD52387D.png
 

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Disconnect it and report back.
Well I don’t have my fuel line quick disconnect tools here at the house. The fuel filter and pump is on the other side of the engine, so I don’t know if this line terminates into something or is just one piece under the motor to the pump.

I’ll be able to see when I take the dog house out to do my annual service next week. Hoping to figure this out and just bring the parts to fix.
 

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Yes 0w059999 and under.

I don’t see the line or fitting in the Mercruiser catalog on their website.

There is a fuel rail plug on the intake manifold and fuel rail page, and the fuel pump page references bulk fuel line from the regulator to the intake manifold.
Believe you'll need a fuel line quick disconnect tool... I want to say 3/8th in size.... Local auto parts stores do sell the tools sort of cheap.

248M0122042HOSE ASSEMBLY, Fuel Cooler to Fuel Rail864513SS/ACT
magnify.gif
$123.33$116.151

8M0122042--front--500.jpg
 

F.U.IRS

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On the 496 it goes around to the fuel filter/ pump module
 

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Believe you'll need a fuel line quick disconnect tool... I want to say 3/8th in size.... Local auto parts stores do sell the tools sort of cheap.

248M0122042HOSE ASSEMBLY, Fuel Cooler to Fuel Rail864513SS/ACT
magnify.gif
$123.33$116.151

8M0122042--front--500.jpg

Thank you!

Yes indeed, a disconnect tool is needed. Appears to be 3/8” but I have 5/16” too. I have the tools at home.

Based on that picture is appears that the line may not be rebuildable. Mine is leaking where the steel meets the brass.

That may be a stock photo. I believe my fuel line is longer than the one pictured.
 

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Thank you!

Yes indeed, a disconnect tool is needed. Appears to be 3/8” but I have 5/16” too. I have the tools at home.

Based on that picture is appears that the line may not be rebuildable. Mine is leaking where the steel meets the brass.

That may be a stock photo. I believe my fuel line is longer than the one pictured.
Any auto parts store has those for less than the price of lunch....just go pick up another set.
 

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Any auto parts store has those for less than the price of lunch....just go pick up another set.

No need. I don’t have a replacement fuel line in hand.

I’m going to be back in a week or so to service the boat anyway so I can order the part in the meantime when I can verify the part number.
 

JJ McClure

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Why would Mercruiser call a 350 a 6.2?
Are they bad at math or the metric system?
Probably just an o ring lof
 

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Why would Mercruiser call a 350 a 6.2?
Are they bad at math or the metric system?
Probably just an o ring lof

Mercruiser does not. On their website it is referenced as a 377/6.2. CP seems to have their diagrams merged or otherwise incorrect.

The 377 engine externally is identical to the 350 of the same year. So the hose in question would (should?) be the same for both. I don’t see how the fitting on the end of the hose comes apart but agreed it is an O ring or seal of some sort.
 

JJ McClure

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But it’s odd. A 6.2 is 377. LS based. A 5.7 is a 350. Probably Vortec based. How could they look the same? Did GM ever make a 5.7 LS engine?
 

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But it’s odd. A 6.2 is 377. LS based. A 5.7 is a 350. Probably Vortec based. How could they look the same? Did GM ever make a 5.7 LS engine?

This is not LS based. It is SBC based. Think 383 without the .030” overbore.

Yes it is all Vortec SBC stuff.
 

JJ McClure

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That clears up my confusion. That finally makes sense. Guess it’s time to make a new cocktail.
 

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GM junk. Pain in the ass

This is the Mercruiser junk actually :) the GM junk just has the quick disconnect to the line.

I mean it’s 20 years old, so not the end of the world as long as the engine does not need to come out to replace the fuel supply line 😂.
 

Shlbyntro

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View attachment 1216509

I’ve got fuel dribbling from this fuel line where it goes into what looks like a fuel rail quick disconnect adapter. It is leaking from the brass fitting where it connects to the silver fitting.

Is this rebuildable once disconnected? Or do I need a new fuel line?

Engine is 2004 6.2 MX. I tried a different prop to no avail.

@Shlbyntro any pro tips?
you need a new fuel line. its merc specific. dont forgrt the special disconnect tools, the plastic ones work better than the metal ones
 

LargeOrangeFont

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you need a new fuel line. its merc specific. dont forgrt the special disconnect tools, the plastic ones work better than the metal ones

Thank you sir. Do you know or could you look up what the line part number is specifically?
 

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0W021067 shows your engine to be an MERCRUISER 6.2L BRAVO MPI model number 4R42027RS.

Item number 24 in the following link is your fuel hose assembly.


 

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But it’s odd. A 6.2 is 377. LS based. A 5.7 is a 350. Probably Vortec based. How could they look the same? Did GM ever make a 5.7 LS engine?
Ls1 and ls6’s are 5.7L.
 

Orange Juice

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View attachment 1216509

I’ve got fuel dribbling from this fuel line where it goes into what looks like a fuel rail quick disconnect adapter. It is leaking from the brass fitting where it connects to the silver fitting.

Is this rebuildable once disconnected? Or do I need a new fuel line?

Engine is 2004 6.2 MX. I tried a different prop to no avail.

@Shlbyntro any pro tips?
Replace with AN fittings, and steel braided (or similar) line. 😉
 

OCMerrill

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This is not LS based. It is SBC based. Think 383 without the .030” overbore.

Yes it is all Vortec SBC stuff.
Thats a good engine. Ultra reliable. I cant say much about all the Mercury shit attached to it. Most the time they nail it but when they fail they stick their head in the sand.

Mercury F'd us over pretty good marinizing 5.9 Cummins engines.
 

Mandelon

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1. I'd try a second zip tie first.

2. Really you guys? No one? Here: Have you tried a different prop?

Carry on, my work is done here.

;)
 
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