1984 Hunter Fuel Tanks

Jul 27, 2020
14
Hunter 34 Kingston
So I went to check the boat this weekend I had not been out to check on it in 5 weeks and found that I had some diesel fuel maybe a 1/2 cup (maybe less) outside the tank in the drop in mold for the tank. (between the out side tank wall and fiber glass mold to hold fuel tank) I checked hoses and hose fittings but did not see any obvious point of leak. I do have a suspicion the seal for my fuel sensor pick is leaking a little (middle top). I filled the tank for winter and the boat is on the hard here in Canada Ontario and we have had some mild days high teens. Would fuel expansion explain the diesel outside the tank. Or would it be more likely that I have small leak in the plastic tank that I can not see. Any thoughts or experience would be appreciated, and if anyone has replaced there tank with a new one if they still have the information or contact info it might help if I need to replace the tank. Hopefully it is not the tank. Thanks everyone in advance to any help.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,224
CAL 35 Cruiser #21 moored EVERETT WA
Your boat is 36 or so years old. Any idea if previous owners have repaired/messed around/modified any of the fuel system?

Your discovery is not a surprise, more of an inconvenience. Boats and their systems age. The event shows up as a surprise. We the owners are then challenged to become detectives and start to find the cause of the problem and correct it. It seems simple, but can become an experience like Alice falling down the Rabbit Hole.

Put a diesel/oil pad in the bilge to absorb any more leaking fuel.

An overfill can force fuel to leak from a weak gasket. Time to examine from the tank to the engine the fuel system. Checking hoses for cracking and snugging up all connections. Use a clean rag or paper towel to wipe and inspect the system. When you come across fuel on the rag/towel you have the first of possible suspects to address.

Good luck. You're at the best time to begin the inspection. Have it finished before spring and you'll be again sailing.
 
Jan 7, 2011
5,642
Oday 322 East Chicago, IN
So I went to check the boat this weekend I had not been out to check on it in 5 weeks and found that I had some diesel fuel maybe a 1/2 cup (maybe less) outside the tank in the drop in mold for the tank. (between the out side tank wall and fiber glass mold to hold fuel tank) I checked hoses and hose fittings but did not see any obvious point of leak. I do have a suspicion the seal for my fuel sensor pick is leaking a little (middle top). I filled the tank for winter and the boat is on the hard here in Canada Ontario and we have had some mild days high teens. Would fuel expansion explain the diesel outside the tank. Or would it be more likely that I have small leak in the plastic tank that I can not see. Any thoughts or experience would be appreciated, and if anyone has replaced there tank with a new one if they still have the information or contact info it might help if I need to replace the tank. Hopefully it is not the tank. Thanks everyone in advance to any help.
I had a fuel “overflow” once on my 1996 Hunter 280...during the winter. I believe it was expansion of fuel (I must have over-filled it). My tank was plastic also, and those are not prone to holes, but maybe a crack at a fitting.
I think mine leaked down the fill tube or vent when the level got too high.

Greg
 
Jul 27, 2020
14
Hunter 34 Kingston
Your boat is 36 or so years old. Any idea if previous owners have repaired/messed around/modified any of the fuel system?

Your discovery is not a surprise, more of an inconvenience. Boats and their systems age. The event shows up as a surprise. We the owners are then challenged to become detectives and start to find the cause of the problem and correct it. It seems simple, but can become an experience like Alice falling down the Rabbit Hole.

Put a diesel/oil pad in the bilge to absorb any more leaking fuel.

An overfill can force fuel to leak from a weak gasket. Time to examine from the tank to the engine the fuel system. Checking hoses for cracking and snugging up all connections. Use a clean rag or paper towel to wipe and inspect the system. When you come across fuel on the rag/towel you have the first of possible suspects to address.

Good luck. You're at the best time to begin the inspection. Have it finished before spring and you'll be again sailing.
Thanks.. I am hoping to solve any issue before the spring.. the previous owner did not mention any issues with the fuel system other then he had a hard time bleeding the air out when he changed the fuel filter before the sale. I think I have some cold days, in some tight spots this winter. But no better way to get to know your boat then getting your hands a little dirty.. Thanks for the tips,
 
Nov 6, 2006
10,099
Hunter 34 Mandeville Louisiana
My fuel return line cracked and puddled fuel on the tank top after a full tank expanded as it warmed.. The line was over 20 years old.. kinda tough to get to to change but ya gotta do it.. The tank itself did not come with a level gauge so I think you are right in suspecting that as a leak point too. Following is what I found on the label on my poly tank. Inca is still in business and with the model number, probably would make a new one if that is what you need.. A big problem is that you can't get it out without cutting a chunk of fiberglass out to make a hole big enough.. side note.. several owners have reported a capacity of closer to 20 or 21 gallons rather than the 25 stated by the factory..

Products 615-383-6020 Inca marine, in Nashville.

Date 10/84 , Material CL-100 (crosslinked ?)

Capacity 25 Gallons, Model FO-2500

Serial # 66899-1083399

Wall 0.200”
Inca Molded Products (ndt.org)
 
Last edited:
Jul 27, 2020
14
Hunter 34 Kingston
I had a fuel “overflow” once on my 1996 Hunter 280...during the winter. I believe it was expansion of fuel (I must have over-filled it). My tank was plastic also, and those are not prone to holes, but maybe a crack at a fitting.
I think mine leaked down the fill tube or vent when the level got too high.

Greg
Thanks, I did top up the fuel just after it was on the hard for the winter, it is possible maybe I did not leave enough room for fuel expansion and I have a bad or cracked fitting allowing some fuel to escape. I will also check my fill hose and fitting. It looked like it had some surface cracks but nothing was obviously leaking from it. Thanks for the tips
 
Jul 27, 2020
14
Hunter 34 Kingston
My fuel return line cracked and puddled fuel on the tank top after a full tank expanded as it warmed.. The line was over 20 years old.. kinda tough to get to to change but ya gotta do it.. The tank itself did not come with a level gauge so I think you are right in suspecting that as a leak point too. Following is what I found on the label on my tank Inca is still in business and with the model number, probably would make a new one if that is what you need.. A big problem is that you can't get it out without cutting a chunk of fiberglass out to make a hole big enough.. side note.. several owners have reported a capacity of closer to 20 or 21 gallons rather than the 25 stated by the factory..
Products 615-383-6020 Inca marine, in Nashville.

Date 10/84 , Material CL-100 (crosslinked ?)

Capacity 25 Gallons, Model FO-2500

Serial # 66899-1083399

Wall 0.200”
Inca Molded Products (ndt.org)
thanks the information and advice. I will have to check all my lines better I did a visual but the tip of a white rag or something that will show any trace of fuel while wiping and checking may provide further evidence to what the main issue is. Hopefully it is not the plastic tank and just a cracked hose of bad seal.
 
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Jan 4, 2006
7,273
Hunter 310 West Vancouver, B.C.
I will assume that you are correct about the tank being plastic. The boat is 36 years old and poly tanks were not in vogue back then. Check the interior for major signs of renovation to remove the old tank and install the new poly tank.

Other than that, try wrapping every small point you suspect of leaking with paper towel and hold in place with duct tape. Check frequently for signs of leakage. Hope for a heat wave to blow through again and possibly expand the fuel volume to either prove or disprove this theory.

Good luck and let us know.
 
Jul 27, 2020
14
Hunter 34 Kingston
I will assume that you are correct about the tank being plastic. The boat is 36 years old and poly tanks were not in vogue back then. Check the interior for major signs of renovation to remove the old tank and install the new poly tank.

Other than that, try wrapping every small point you suspect of leaking with paper towel and hold in place with duct tape. Check frequently for signs of leakage. Hope for a heat wave to blow through again and possibly expand the fuel volume to either prove or disprove this theory.

Good luck and let us know.
thanks. I think it is plastic, but it could be poly tank. It appears to be the original tank no sign of any removal or major work in that area.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,224
CAL 35 Cruiser #21 moored EVERETT WA
I think I have some cold days, in some tight spots this winter. But no better way to get to know your boat then getting your hands a little dirty..
Absolutely true. At least if the sun is shining the boat might be above freezing. I got a teeshirt for the experience. Still working on the check list for my boat. Pretty sure just as I get done something more will occur. But it is all good. I get to do it on a boat. I get to meet new people. Most everyone on the dock is pleasant and walks about with a smile. I think it is because they are on their boat.
 
Jul 27, 2020
14
Hunter 34 Kingston
Absolutely true. At least if the sun is shining the boat might be above freezing. I got a teeshirt for the experience. Still working on the check list for my boat. Pretty sure just as I get done something more will occur. But it is all good. I get to do it on a boat. I get to meet new people. Most everyone on the dock is pleasant and walks about with a smile. I think it is because they are on their boat.
It is all good fun and a way to pass the time, and if i didn't know what to spend my money on the boat will always remind me.
 
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RoyS

.
Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
No need to top off your tank for the winter.
 
Dec 14, 2003
1,433
Hunter 34 Lake of Two Mountains, QC, Can
interesting. your aft cabin for the batteries and fuel storage is a little different to mine. I think I like the pictured set up better then what I have.. thanks for the picture and info.
FYI, my 34 is also an 84. Unless PO has made mods, tank configuration must be same as yours. Picture was taken from the stern cabin. Batteries are on the starboard side in-between tank & hull so not visible from angle of the picture, ...and admittedly a little hard to reach through the opening, unless I crawl in. But tank fittings are easily reached and fridge compressor cn be serviced from there if need be. Attached pics will give you a better idea of that mod. You can siphon out the spilled fuel with a small hose inserted all the way to the bottom, near the inboard front corner of the tank. Points made in previous posts are all good. As for overfilling in the fall with the idea of avoiding condensation, we have all been there and done that. No condensation to speak of with our poly tanks ! It is the rise of temperature that causes the spill. Generally in the Spring, but the unusual temps we've had lately might have caused it. You may want to pump some fuel out with an oil extractor to avoid a greater spill with Spring temps. Good luck
 

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Jul 27, 2020
14
Hunter 34 Kingston
FYI, my 34 is also an 84. Unless PO has made mods, tank configuration must be same as yours. Picture was taken from the stern cabin. Batteries are on the starboard side in-between tank & hull so not visible from angle of the picture, ...and admittedly a little hard to reach through the opening, unless I crawl in. But tank fittings are easily reached and fridge compressor cn be serviced from there if need be. Attached pics will give you a better idea of that mod. You can siphon out the spilled fuel with a small hose inserted all the way to the bottom, near the inboard front corner of the tank. Points made in previous posts are all good. As for overfilling in the fall with the idea of avoiding condensation, we have all been there and done that. No condensation to speak of with our poly tanks ! It is the rise of temperature that causes the spill. Generally in the Spring, but the unusual temps we've had lately might have caused it. You may want to pump some fuel out with an oil extractor to avoid agreater spill with Spring temps. Good luck
thanks for the pictures.. i like your access hatch and plan to do the same to mine starting this weekend..
 
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splax

.
Nov 12, 2012
694
Hunter 34 Portsmouth
I found fuel like you but my fuel fill hose was the culprit. It was degraded underneath, out of sight.
 
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