Mercury 60hp Bigfoot fuel leak

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Tully
Posts: 196
Joined: Sat Mar 05, 2011 6:45 am
Location: Table Rock Lake. SW Missouri

Mercury 60hp Bigfoot fuel leak

#1 Post by Tully » Wed Apr 22, 2015 7:47 am

Getting boat ready for the season. Removed engine cover, put on muffs and let it idle to warm up before changing oil. Noticed fuel spraying from left side of engine. A block about the size of a cig pack called the fuel cooler. Attaches to vapor separator. Removed top plate to find 4 o'rings sealing the lines. O'rings not sold separately and the cooler lists for around $500.
Found some o'rings that fit as well as possible. Took to local Merc dealer to install fuel line clamps. Oretiker type clamps that require a special tool to crimp the clamp. Dealer had to order clamps so I'm waiting to see if the substitute o'rings work. If not, there goes $500 for a new cooler.
The fuel line plate attaches to the cooler with 2 #10 machine screws. Don't understand why the o'rings are not sold as a repair part.
2008 Tracker 24' Party Barge
Mercury 60 hp Big Foot 4 stroke
2011 Ford F150 Ecoboost
Point 25
Owl Creek Cove
Table Rock Lake
Southwest Missouri

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teecro
Posts: 1009
Joined: Sat Jul 12, 2014 7:23 am
Location: Sunset Bay, TN

Re: Mercury 60hp Bigfoot fuel leak

#2 Post by teecro » Wed Apr 22, 2015 7:50 am

Tully wrote:Getting boat ready for the season. Removed engine cover, put on muffs and let it idle to warm up before changing oil. Noticed fuel spraying from left side of engine. A block about the size of a cig pack called the fuel cooler. Attaches to vapor separator. Removed top plate to find 4 o'rings sealing the lines. O'rings not sold separately and the cooler lists for around $500.
Found some o'rings that fit as well as possible. Took to local Merc dealer to install fuel line clamps. Oretiker type clamps that require a special tool to crimp the clamp. Dealer had to order clamps so I'm waiting to see if the substitute o'rings work. If not, there goes $500 for a new cooler.
The fuel line plate attaches to the cooler with 2 #10 machine screws. Don't understand why the o'rings are not sold as a repair part.
YES YOU DO !!! $$$ :censored
T CRO
2017 Berkshire CTS 24 RFX with Yamaha F150
2015 Caravelle 16 EBo with Mercury 90

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jgrimes295
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Joined: Wed May 09, 2018 7:03 am
Location: Fredericksburg, VA
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Re: Mercury 60hp Bigfoot fuel leak

#3 Post by jgrimes295 » Sun Oct 07, 2018 10:59 am

So I've had a similar issue:

Started as a VST problem. We have no trailer for the boat....it stays in the water at the marina until November where it goes into dry storage, so when the VST issue surface, I sailed around to that marina/mechanic. They spent a day or two on it....had to rework it a couple of times...then said its all fixed.

I took it for a test run and sure enough, the bog-down/stall out issue appeared to have been fixed. And it wasn't "peeing" out of the overflow any more.....Great!

Went out about 3 days later for a cruise with my first-mate and when we pulled into our little cove and anchored up, smelled gas. Look over the transom and sure enough, a small fuel bloom. Started the engine again and saw that the thing was leaking....again...but this time it was kind of just gushing down the bottom rim of the cowling.

Back to our slip. Came down the next day and removed the VST myself.....took it home and dismantled it...thanks to a Youtube video, I knew exactly what to look for and frankly, the dismantling and cleaning were pretty easy. I found some deposits on key points in the pump. Specifically in the tube that comes off of the regulator and dumps back into the tank, as well as a hardened and crusty o-ring for same regulator. (Ordered parts - Amazon.....$20 total). While waiting for those, I took time and cleaned the crap out of the other pieces of the VST. Found yet another piece of debris in the float valve that had caused IT to start sticking again.

So....(I know...this is becoming an epic).....Put that all back together...head down to the marina and put the engine back together. Left the cowling off and started the engine.....once it self-primed...it caught and ran like the champ that it is....and then.....spraying out of the fuel cooler (attached to the VST) is fuel. A nice flat, fanned out spray. Very clearly coming from under the top plate of the cooler. Ok...tighted screws....didn't work.

Took the cooler (only) off and brought it home. On the bench I find that its just a block of metal (with ports), and two screws on each plate holding the fuel and water lines on. Looking at those....small (8mm) O-Rings...flattened out and a little brittle. Having already read about this as part of this forum and a few others I knew that checking Mercury was useless....and the assembly must be made of gold as a new unit goes for about $500.

Ok....so of all places, Lowes has O-rings that are the correct inner-diameter. They have two different thicknesses....the one that is closest in size is the #10, 5/16th Inner diameter and 1/16th thickness. ( I got those and the 3/32nd versions as well). I've installed the smaller rings and have reassembled the cooler. I pretty confident that this will work, but if not, I'll use the thicker rings....should take about 15 minutes to change them out.

I'll post the results after I get back to the boat and test this......I'm also putting together a video to post on YouTube.....stay tuned!

Jim
2011 Harris Floteboat
Cruiser CX200
"Sandy's Shore"
Home Port - Anna Point Marina
Lake Anna, VA!

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Rick McC.
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Joined: Fri Mar 31, 2017 7:12 pm
Location: Weeki Wachee, Fl

Re: Mercury 60hp Bigfoot fuel leak

#4 Post by Rick McC. » Thu Oct 25, 2018 7:59 pm

Jim:

So how did it go?
Rick

Sights are for the unenlightened.

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