fuel tank replacement

  • May 21, 2012 10:46 AM
    Reply # 926461 on 772857
    Deleted user

    As I mentioned in an earlier post, I have discovered that the previous owner replaced the steel fuel tank with a roughly 100 gallon poly tank with not steel tank.  I have completed removing the entire galley and dinette "furniture":  a full "gutting" is a more proper term. 

    Unfortunately, I found significant water damage from leaking deck fills and starboard stanchions.  While the dry rot is atrocious looking, the fixes necessary are not drastic, but none-the-less are involved.  Hopefully, we found all of the leaks, but an upcoming rain storm and a self-inflicted water hose test will confirm.

    Now that I have a completely vacant galley/dinette area, I can remove and replace the plywood sub-floor:  a victim of the water leakage, as well.  When the floor is exumed, I expect to find 3 stainless water tanks:  2 saddle and 1 center.  From what I can see, the tanks look fine.  However, I will need to do fill them and test for any leakage.  Hopefully, the leak test will be passed, and I can start reconstructing the galley/dinnette area.

    If leaks are detected, I will explore options of fixing or replacing.  In another boat I fixed a monel water tank with epoxy and glass cloth wrapping (ala West System).  The repair continue to last and perform well into its 15+ year.  However, I will probably choose stainless tanks as a replacement because I am not comfortable with what could go on inside an aluminum tank after exposure to various water supplies.  I want baffles in the tanks, so poly may not work.  Thoughts and/or recommendations would be appreciated!

    My tank inspection and hopeful reuse of the tanks rather than replacement involved a much more drastic gutting of the galley/dinnette area.  While more effort perhaps, it was a more easy option because removing/reinstalling the furniture would have been very difficult.  Firstly, The extent of the water damage and getting to it make the gut-job more palatable.  However, after noticing how well put together the galley/dinnette furniture was, made componentizing the areas almost impossible.

    For those consider the path I chose, please be aware that the structural integrity of the furniture buld by WestSail was/is impressive.  What I anticpated as a relatively easy demolition, turned into a 3 month task:  roughly 20+ full days effort by me alone.  Yes, it is not a project for the less inclined!  However, now that I am ready to remove the sub-floor, I am glad I did it.

    Doug

    s/v Harmony #91

  • May 21, 2012 9:05 PM
    Reply # 927030 on 772857
    Deleted user
    Doug,

    I am in for much of the same.  Ground out old rotten plywood sole supports which were tabbed into the hull.  I am going to use COOSA tabbed in around Moeller poly tanks in the center and ss custom fabbed water tanks in the wings.

    COOSA is a fiberglass composite which never rots and tabs well.  only you cant screw into it so teak blocks will have to be throughbolted to hold the cabin sole together.  It is pricey but it doesn't need the labor of sealing with epoxy so it probably costs the same.

    Fun stuff eh?
  • May 23, 2012 8:44 AM
    Reply # 928468 on 772857
    Deleted user

    Ed, always fun stuff!  I was on the boat yesterday, and was able to expose the water tanks.  Unfortunately, the original tanks have failed on the baffle weld point and now are more airtanks than water tanks!  I will be have new ones made out of stainless.

    The floor members are surprisingly healthy.  I don't belief that I will have to go to the extent that you are with coosa, etc.  However, I have gutted the entire galley/dinnette area and some of the salon because of water damage.  Yesterday, it was raining heavily and I found the source of the waterleaks.

    Most folks have suggested that the teak deck was leaking, but the deck is fine.  The leaks are coming from the cap rail and deck fills.  The deck fills are easy to fix, but the cap rail will be another adventure, and perhaps another subject thread!

     more fun for sure!

    Doug

  • May 25, 2012 8:59 AM
    Reply # 930313 on 772857
    Deleted user

    I was on Harmony yesterday and removed all three water tanks.  while the tanks looked passable at first glance, a more thorough inspections revealed failures at the baffle weld points, as well as heavy corrosion at the corner weld points.  Unfortunately, I had to pump a goodly amount of water out of the tanks, which indicates they were not properly cared for over the years:  New England freezing winters and all.

    I was able to remove the tanks from their spaces and pull them up through the companionway by myself.  I was also able to lower them down to the ground with little trouble. I will use the existing tanks as templates for new tanks.  That construction begins next week, and the investment, while not slight, will be worth the price as I don't want to replace or remove them again!

    While out, I will cover the existing floor members with epoxy/glass.  However, they are in very good shape for some 36 years of doing their job.  Per the recommendation of the tank maker, I will "glue" neopreme spacers under the tanks to prevent them from having direct contact with the hull:  this will also allow for some air movement.  Additionally, I will use neopreme cushioning on the topside hold downs to keep any hydrophyllic wood from making contact.

    I am staying with the 3 tank / 200 gallon tank set-up as was originally designed:  2 @ 50 gallon saddle tanks, and 1 @ 100 gallon central line tank.  while we may add a water maker down the road, our sailing plans should be comfortably accommodated by the original set-up.

  • May 25, 2012 5:36 PM
    Reply # 930660 on 772857
    Deleted user
    What I ended up doing was to downsize my 4 wing tanks so that 4 identical tanks can be fabbed (although they are enantiomers--R and L handed).  In that way my welder was able to set-up to make all the tanks and save on labor and material.  It also allows me to beef up the substructure by adding thicker cabin sole supports. 

    I had a question about your leaks.  Can you elaborate as there was a big leak in this vessel which may or may not have been completely fixed.  The deck fills were perhaps the culprit but you mentioned the caprail as well?  I suspect there was a similar issue here.
  • May 25, 2012 8:02 PM
    Reply # 930849 on 772857
    Deleted user

    Ed, our W42 suffered a significant amount of internal water damage.  Thankfully, all of it can be fixed.  I believe most of the problems staredt small, but through neglect over the years blossomed into a serious issue.

    The leak areas are many.  First, the deck fills were not maintained and lost all of the bedding compound and were basically just sitting in the deck hole.  Fortunately, no damage to the plywood deck core.  Second, on the stern deck there is a round teak plate which covers what may be on many W42s an access to a locker.  Well, on Harmony it is just a round plate that needs to be rebedded.  Third, several of the dorade boxes leak as a result of bedding compound failing:  an easy fix for a minor issue.  Fourth, and the biggest culprit is a leaky caprail.

    During a rain storm the other day, I witnessed water dripping off of the self-tapping screws used to secure the caprail onto the hull/deck flange.  I can see both self tapping scres and through bolts with the through bolts being the hull deck fasteners.  On the aft quarters, sailtrack was through bolted, but I only saw dripping from the self taping screws.  This is good because it is nearly impossible to reach the sailtrack through bolts without a creative fabrication of an extension wrench or removing furniture.

    Anyway, the caprail leaks destroyed the forward freezer bulkheak, the salon berth and ceiling, the aft galley bulkhead by the chart table, and a portion of the aft dinette bulhead.  Thankfully, all of this is a straightforward fix.

    However, fixing the leaky caprail will take a little more work.  I have noticed a sizeable gap, say up to 1/16 of an inch between the caprail and the hull/deck flange plate on the inside of the bulwark:  there was some bedding compound, but it was spotty.  On the outside of the bulwark, the gap is not as wide.  The fix is two parts.  Part A is to chaulk the gap with a good urethane sealant:  I will be using a new product from SystemThree called SA 2100, which is a two part urethane adhesive chaulk.  This should both seal the gap, as well as provide some flex when the boat moves.  Part B is to rebed each screw that attaches the caprail.

    Since I need to refinish the caprail, Part B is pretty much part of the deal.  I will drill out the bungs, unscrew, rebed with urethane sealer (perhaps not the tenacious adhering SystemThree product, but 3M 4200), re-screw, and re-bung.  The re-screwing with sealant should plug whatever leaks are not covered by the chaulking under Part A.

    If that doesn't work, I will try to design an aquaduct like the Romans had in order to make a more positive usage of all of the dripping water!  Well, it must be the epoxy fumes!

    Well, a long winded answer I fear, but I hope it helps.  The outside water seems to roll around the rounded edges of the caprail and follows the path of least resistance into the boat. I would suggest looking at the caprail for a gap like mine, as well as looking up into the bulwark:  you may see signs of water leakage.

    One other area for leaking may be the stanchions which are bolted on the inside of the bulwark.  Although, I have not seen any leakage from those areas.

    I will let you know how the Part A and Part B work.

    Doug

     

  • May 26, 2012 5:17 PM
    Reply # 931452 on 772857
    Deleted user
    Doug,

    Thank you so much!!!  It does help as I am contending with similar issues.
  • August 15, 2012 9:48 PM
    Reply # 1048407 on 772857
    Deleted user
    Progress update:  All dividers for all tanks removed.  New dividers/floor supports maunfactured of Fiberglass laminated COOSA board with Alaskan yellow Cedar stringers to screw new plywood cabin sole into.  I am currently starrting the tabbing into the hull of the tank dividers.  ill take pics after everything is tabbed in.  Used polyester resin for the COOSA (much cheaper---$125/5 gallons vs. $450/ 5 gallons for epoxy).  Using the epoxy to tab to hull (stickier, easier to use, not as volatile---safer, and seals better as well as will tolerate moisture while curing unlike poly resins.

    Fun project.  Lots and lots of hours.  Used plastic tanks---no rot.  Coosa no rot.  epoxy no rot.  Materials about 10k labor, well endless I suppose....
  • August 16, 2012 10:56 AM
    Reply # 1048992 on 772857
    Deleted user
    Doug,

    BTW it was the caprail.  I scraped out all the old caulking, prepped with sandpaper and brushed with denatured alcohol.  Recaulked with Lifecaulk.  I'll test this out.  I am hoping not to have to go to the lengths you did with regard to rebedding and bunging the screws.  The stanchions appear fine.

    Thanks.
  • August 16, 2012 10:26 PM
    Reply # 1049504 on 772857
    Hi Douglas and Edward, I have been following your H20 and fuel tank issues and just read the caprail notes. I have a W42 and  I am resealing the caprail. I am removing the the old calking which is a bear.. It is still very playable almost like gum and sticky. Do you have a good method of getting the old calking out. I am using a utility knife, screw driver, pick and chisels.. I am scraping the underneath outboard edge with the chisel, will sand, put some penatrating epoxy and rebed with polysulfide. I am using polysulfide b/c it is probably what was originally used, can be sanded and painted.

    I also will be dealing with replacing H20 and fuel tanks. I believe that I have leaks from both main H20 and fuel tanks.  Hopefully, the wing tanks are good so that we can use those for now.. Tackle the project later....  it would be great to see any photos that others have taken of the project... Thanks, George