Hunter 310 1997 Fuel tank replacement - pics of aft

[mghunter310]

Hi

my Hunter Ezell al tank has finally given up and started to leak.

I've read all the posts as to how I need to remove / cut the rear aft timber cabin wall to get it out and new one in, but seems no one posted any pictures or tips.

So, can I take the timber wall out in one piece or do I need to cut it in half ?

I can see the tank is fitted against the wall and seems to be bolted to the timber wall, so cutting just an access hatch does not seem possible.

Any tips / pics appreciated

 

[sailcapt340]

Are you saying you have to cut the wall itself that we see in your third photo?
When I enlarge you picture, I see a molding strip behind the aluminum pole in the picture to the right.
On my 340 those have screws in them that hold the wall (panel) in place. All I have to do is remove the 2 strips of molding on either side, fold back a small amount of foam wall covering to expose 2 more screws on both ends and pry out the panel.
Can you push against the wall self and feel any movement in the panel on the top or bottom? The bedding needs to be removed, there may be screws behind that. That should come out in one piece, with a little effort. Once out it will open the entire back area.
I do need a small screw driver to hold the panel while I put the screws and molding back in place though.
It could be held in place by the longer strips butting against it. In which case they would need to be removed.
I hope this helps in some way.

 

[mghunter310]

Thanks - there are a few screws holding the wall that I can see inside the rear battery area hatch but it seems the ends of the wall are fiberglassed in and that port side would be impossible to get to (unless you were a very small child) - see pic

Even if I could unscrew and remove the wall, I can't get to the screws holding the tank to the wall (albeit I guess I could drill them out) but still may not be able to move the wall as the tank is pressed up and screwed inside the rear battery hatch areas (too far to reach)

I've also measured the tank the best i could (its not a square one from what I can see)


ps- the "borrowed" the original aft wall photo until I could get onto the boat

 

[JamesG161]

I've also measured the tank the best i could (its not a square one from what I can see)

You are correct, that tank is shaped to fit the hull.
I have the same type tank same year as yours.
There may be a shop drawing of your tank available from links to Marlow Hunter past info.
Try calling here for most information...
1-to-1 Hunter Support and Service

Jim...

 

[JamesG161]

That wall fits in a grove and can be removed, possibly without a cut.

I can help with that potential cut by... Where to cut and and how to put it back looking very nice too.
Jim...

PS: That tank can be cleaned and weld fixed and put back.

 

[mghunter310]

Thanks Jim

Would be grateful for any tips / ideas re cutting / removal

On your boat, is the aft wall fiberglassed to the hull as that is what it looks like in the pic ?

There is no way I can get into that space to cut it out from the inside and it looks like the tank butts up against that section so cutting it from inside the aft cabin is also a bit dicey (assuming I can remove and fix the current tank)
regards

 

[mghunter310]

Had some spare time to row out and can see the possible removal of the aft wall as one piece (and even managed to remove the bolts holding the tank to the wall).

However, what I can't work out is why the backside of the aft wall looks like there are no cuts or joins whereas the front looks like a jigsaw (this is the starboard side)

Also the battery case is bonded to the aft wall and the aft wall seems bonded to the hull

I guess keep taking the screws out and see what happens.

I also suspect the water damage to the port side timber was due to a water leak from the cockpit electrical cord opening and which may have now contributed to the tank leak.

 

[JamesG161]

My 50 gallon tank is under the Aft cabin bed and easy to see too.
If I had to remove it, I would old have the Deck of the bed in my way.

If you cut the wall, make a vertical cut, Top to Bottom.
On return fix, a use a thin Teak board to cover that cut. Looks like an extension joint.

which may have now contributed to the tank leak.

If the outside of tank is corroded, then you have an easy fix. Perhaps no removal needed.

Most tanks leak from water in the fuel over the years.
____

Also the battery case is bonded to the aft wall [] and the aft wall seems bonded to the hull

That wall separates cabin from the Rudder and steering [my guess].
If you do not have your Owner's manual look here...
HunterOwners.com downloads

Part 2 , page 61 A, has a drawing that might help.

Jim...

 

[smokey73]

Ezell, in Perry FL, probably has a drawing of the tank. The did for my 1994 Hunter 40.5. Its worth it to give them a call. (850) 578-2558 There is a very nice lady there I worked with to have a replacement tank made out of thicker aluminum than the original. They even customized it for me with an extra pickup/return for a dedicated fuel polishing system as well at two openings on the top for cleanout (on both sides of the baffles.) I was very pleased with the workmanship and it fit like a glove and I didn't lose any capacity that comes with selecting a tank that doesn't fit the location perfectly.

 

[smokey73]

In my tank, the leaks were in the bottom of the tank and were slow leaks through corrosion holes that looked like "wet cardboard". You could push an ice pick through the porous area on the tan bottom. There were several of these holes.

I see by your avitar that you are in Sidney. Is that Sidney Australia? If so then it may be more cost effective to try and repair the leaks, maybe by welding a new bottom on the tank if that is the location of the leaks. Welding aluminum by a skilled welder with the right experience once the tank is out should work considering it was welded to begin with. Best of luck

My tank came out up through the port lazarette. It was a tight fit but it worked.

 

[smokey73]

ps: I removed the whole back divider since I had some wood rot because of an undetected leak but I don't think I would have had to do this to remove the tank. It did make it easier though. I replaced the back bulkhead with a piece of exterior PVC board and it looks fine. The original was white painted plywood to begin with so it looks the same. I painted the board with a pvc compatable paint that matches the interior color. Note that was an opening in the bulkhead but I don't see that in your pictures.

 

[mghunter310]

Thanks

I've emailed Ezell Industries but no response so far - I saw some earlier posts that others got the tank drawing and was hoping someone might post it up - if I get it, it will go up

Still stuck on why the divider seems glued in / fiberglassed in to the sides of the hull given it does not seem to be structural and best option to cut it out (eg without putting a hole in the hull)

I suspect you have a bit more room to play with on the 40 - on the 31 there is the steering shaft smack bang in the middle so no way to get the tank around it that I can see, and anyway would not come out thru the starboard lazerette anyway given tank size (the port one is for gas tank storage, is the same opening size and is built in / sealed up anyway)

I'm now toying with the idea of opening up the whole back area behind the divider, removing the tank and using the wasted space for storage.

I'd then use a flexible diesel tank in the middle keel channel where the rubber exhaust and fuel lines run - seems I would just need to extend the filler and vent pipes - sample tank pic would need a few fittings moved but seems possible

 

[mghunter310]

The saga continues

I decided to try the port lazarette (gas bottle storage) and found it was but siliconed in. So after cutting the silicon bead all around and removing all the gas fittings, it pulled up, only to get stuck halfway. A bit more pulling and it cam free.

Seems the drain is connected to a short hose to the outlet around the starboard side and gave was (rusted clamp) - lesson is to unclamp the hose from starboard outlet side first and it will just lift out ( and in reverse when refitting)

Anyway, removing the gas bottle storage gave access to a whole new world. After removing all hoses (had to slice the fuel outlet and return rubber hoses as they would not come off and no real room to pull them, I cut the foam out with a hand saw, turned the tank around to pull out and got stuck

Seems you also need to remove the hose ends as they reduce the clearance - using your feet on a 14mm spanner works best re leverage.

Anyway, having done all that, the tank would still not clear the lazarette as a) the corner stopped it getting out and b) the fuel inlet fitting was stuck under the lazarette.

I think Hunter though this was a good idea but never tested it as they probably fitted the tanks before attaching the deck .

After considering all options (including maybe cutting off the corner of the tank to get some clearance), I have resigned to going to to removing the aft wall, which has a few screws but is fiberglassed in at the ends (sort of a joke I think by the builders to lull you into thinking its a easy option). Now that the tank is turned I guess its a smaller hole to get it out so I can avoid the fiberglassed bits (I hope)

Some pics that might helps someone in the future.

Also Ezell came back with quote for a new tank of around US$786 (plus shipping) so seems like either a repair or flexible bag is the go (which might also cut down on any condensation as it collapses as the fuel is used and plenty of realestate at the rear to put it in ).

 

[mghunter310]

Update - so spent a few hours with a electric saw blade cutting thru the wall and avoiding any cables etc

In the end two straight cuts seems like the best way, mainly due to the height of the tank.

The bottom of the panel is fiberglassed in (probably for water proofing only) , the top is loose and just screwed in.

Next problem is the tank (430 mm wide) would not fit thru the door (400 mm wide) , so had to take the door and frame off )just screwed in) which made the opening around 460mm.

Now to find where / why the tank is leaking (no obvious holes but suspect a small pinhole somewhere).

Still leaning towards a flexible tank (would just need to extend the filler hose) in front of the rudder post (around 800mm to the back of the hull) plus clean up the wiring (seems Hunter coiled extra wire just in case you might extend the rear of the boat by 10 feet

 

[JamesG161]

Now to find where / why the tank is leaking (no obvious holes but suspect a small pinhole somewhere).

You might use the pressure of shop vac using the blower side to detect the leak.
Water fill is for sure, but must be done in a safe spot for diesel leak potential.

Note: There are "baffles" inside the tank.

Jim...

PS: Nice job on the panel cut, should be easy to hide the vertical cuts, with teak strips.

 

[mghunter310]

So cleaned the tank up and went looking for holes somewhere near the welds only to be sorely disappointed - welds are great. Even the inside baffle welds are not visible on the outside of the tank.

Filled the tank with some water (and detergent to get rid of any final gunk) and positioned it as it would be in the boat.

A few minutes later , had a puddle of water from an unexpected area of the tank. Looking into the tank against the sun confirmed 3 holes

Seems if Hunter had sat the bottom on the tank off the fiberglass on top of the foam it might have saved the tank, as it seems the 3 holes are from the outside in (or maybe both). I suspect salt water pooled and sat between the tank and fiberglass for 24 years and etched the holes. Otherwise the tank is in excellent condition.

The challenge now is do I get the tank welded only to find new holes appear later, or just go with the flexible tank option (and get some rear space to boot)

 

[JamesG161]

I suspect salt water pooled and sat between the tank

Salt water pooling against most mild steel is not recommended.

Still possible to weld a patch or buy and install that replacement. The OEM one lasted 24 years.
Jim...

 

[smokey73]

Still possible to weld a patch or buy and install that replacement. The OEM one lasted 24 years.
Jim...

Plus, the new tanks built by EZELL are made of thicker Aluminum. I ordered the replacement tank from EZELL and am very pleased with it. They also put in two cleanouts on the top of the tank and extra pickups/returns for me. What kind of fuel capacity will the bladder tank give you? Have you considered that it might reduce the selling price at some point in the future if the fuel capacity is reduced? Just asking.