Replacing Fuel Tanks on OA 50 Mk1. Looking for Lessons Learned
- Thread starter AdamWalsh
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Comodave
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There are many threads on fuel tank replacement. Not necessarily on O As but good info anyway. Try a search for fuel tank replacement.
jungpeter
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Hi Adam,
An excellent question, but unfortunately a bit open-ended. So here's some questions to (hopefully) envoke substantive input to your question, and narrow the bandwidth on this thread.
a. Where is the boat located? On the hard in the winter? Afloat at a full-service marina and/or boatyard? On a private dock somewhere? Close to home?
b. What is your level of do-it-yourself (DIY) comfort? If you're planning a DIY replacement, you're going to have to dig into many systems aboard (furniture, electrical, plumbing, etc.) to replace your tanks.
c. More importantly, what is your level of DIY capabilities? Given your initial query, I expect you haven't tackled a project like this before. And it's a BIG one! Arguably the biggest project a boat owner can face during his ownership.
d. How long do you want to own this boat?
e. What are your usage history and plans for this boat? Marina hopping? Multi-day off-grid trips?
f. Have you engaged your insurance company and/or a surveyor to determine the extent of your fuel tank issue(s)?
g. What is the size of your wallet? Replacement of fuel tank(s) is typically a VERY expensive proposition, at least to do it correctly. And if you're planning on having professionals do this work (see b. above), then your original posting hopefully will lead you to these professionals.
Unfortunately, your original posting may evoke many, many responses that will be less-than helpful. In particular, the "howler monkeys" may chime in and post advice to "pour some mouse milk into the existing tanks. It'll work just fine." Or others that suggest rote replacement of large tankage with multiple small (usually plastic) fuel tanks. And without knowing intimate details of your particular situation, or intimate details of the OA 50 Mk 1, much of this advice may be fruitless. Given I have absolutely no knowledge of either, anything I may add at this point will be equally fruitless. Other than to say "been there, done that" on multiple large powerboats in the past.
Best of luck in this venture. And kudos for posting a search for "cost effective" vs "cheapest" solutions to this issue. They very definitely aren't equivalent. And "cost effective" and "DIY" are also non-equivalent, depending on who's asking.
Regards,
Pete
An excellent question, but unfortunately a bit open-ended. So here's some questions to (hopefully) envoke substantive input to your question, and narrow the bandwidth on this thread.
a. Where is the boat located? On the hard in the winter? Afloat at a full-service marina and/or boatyard? On a private dock somewhere? Close to home?
b. What is your level of do-it-yourself (DIY) comfort? If you're planning a DIY replacement, you're going to have to dig into many systems aboard (furniture, electrical, plumbing, etc.) to replace your tanks.
c. More importantly, what is your level of DIY capabilities? Given your initial query, I expect you haven't tackled a project like this before. And it's a BIG one! Arguably the biggest project a boat owner can face during his ownership.
d. How long do you want to own this boat?
e. What are your usage history and plans for this boat? Marina hopping? Multi-day off-grid trips?
f. Have you engaged your insurance company and/or a surveyor to determine the extent of your fuel tank issue(s)?
g. What is the size of your wallet? Replacement of fuel tank(s) is typically a VERY expensive proposition, at least to do it correctly. And if you're planning on having professionals do this work (see b. above), then your original posting hopefully will lead you to these professionals.
Unfortunately, your original posting may evoke many, many responses that will be less-than helpful. In particular, the "howler monkeys" may chime in and post advice to "pour some mouse milk into the existing tanks. It'll work just fine." Or others that suggest rote replacement of large tankage with multiple small (usually plastic) fuel tanks. And without knowing intimate details of your particular situation, or intimate details of the OA 50 Mk 1, much of this advice may be fruitless. Given I have absolutely no knowledge of either, anything I may add at this point will be equally fruitless. Other than to say "been there, done that" on multiple large powerboats in the past.
Best of luck in this venture. And kudos for posting a search for "cost effective" vs "cheapest" solutions to this issue. They very definitely aren't equivalent. And "cost effective" and "DIY" are also non-equivalent, depending on who's asking.
Regards,
Pete
mvweebles
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I can't speak to OA50, but I just had my steel tanks replaced in Mexico. I had a pair of 200g saddle tanks, single engine and replaced with four 100g fiberglass tanks. Best I could figure, aluminum tanks are less labor intensive but more expensive materials than fiberglass. Due to low labor costs in Mexico, worked out to be a push. In the US, it would have been prohibitive to even consider fiberglass.
I chose Fiberglass as I believe it's the most durable material for fuel tanks. I had a lot of other work done so it's a bit hard to tell, but if had had nothing but those done, probably could have had it done for around $9k, might have been closer to $10k by the time I was done with some super-slick fiberglass pipe fittings and access plates used for fracking.
Doing it cost effectively. By far, replacing tanks is top-of-the-mark for scope creep. In a world where scope creep is ridiculous (boat projects in general), tank replacement is far and away has the greatest potential for runaway costs. Stay focused and don't get seduced into "well, while the engine is out, I might as well......."
Here's a list of stuff that are tempting to do at same time. Resist the urge, and you'll preserve your 401k cash position:
I chose Fiberglass as I believe it's the most durable material for fuel tanks. I had a lot of other work done so it's a bit hard to tell, but if had had nothing but those done, probably could have had it done for around $9k, might have been closer to $10k by the time I was done with some super-slick fiberglass pipe fittings and access plates used for fracking.
Doing it cost effectively. By far, replacing tanks is top-of-the-mark for scope creep. In a world where scope creep is ridiculous (boat projects in general), tank replacement is far and away has the greatest potential for runaway costs. Stay focused and don't get seduced into "well, while the engine is out, I might as well......."
Here's a list of stuff that are tempting to do at same time. Resist the urge, and you'll preserve your 401k cash position:
- Replace stuffing box (and cutless bearing)
- Paint engine room
- Paint engine
- Replace engine mounts
- Replace/repair bolt-on engine items such as hoses
- Replace sound proofing
- Replace generator if access is dependent on engine extraction
- Replace batteries with LiFePo4
- Replumb the boat
- Update fuel system - add polishing system, etc.
- Refinish salon floor because you gouged it removing engine
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Hi, Adam:
We replaced fuel tanks on our '81 OA MK 1 (OCEAN DREAM) back in the winter of 2002/03. Most cost-effective method for us, at that time, was to do it ourselves. We had the assistance of a diesel mechanic who was willing to "supervise", offering his advice for the grunt work (of which there's a LOT) when his expertise wasn't needed for direct install/plumbing, etc. Our project was complicated by the fact that we chose to repower with JDs at the same time. New tanks were fabricated in Bellingham WA (by Coastline, I think).
We accomplished this on the hard at La Conner Maritime in Washington state. Project required removing the galley peninsula, erecting a gantry on rails and learning a variety of new vulgarities. It helped immensely to have the feedback and advice of two other MK 1 owners in the PNW (KATHY LEE and MONEY SPONGE) who'd also gone through tank replacements recently.
It was an expensive, frustrating, filthy endeavor. Was it worth it? For us it was as we spent four to six months a year for the next ten years cruising with confidence in the systems we installed, not to mention enjoying how much nicer (and quieter) the engine room became after being fully painted & insulated.
Good luck with your decision making,
Vanessa
We replaced fuel tanks on our '81 OA MK 1 (OCEAN DREAM) back in the winter of 2002/03. Most cost-effective method for us, at that time, was to do it ourselves. We had the assistance of a diesel mechanic who was willing to "supervise", offering his advice for the grunt work (of which there's a LOT) when his expertise wasn't needed for direct install/plumbing, etc. Our project was complicated by the fact that we chose to repower with JDs at the same time. New tanks were fabricated in Bellingham WA (by Coastline, I think).
We accomplished this on the hard at La Conner Maritime in Washington state. Project required removing the galley peninsula, erecting a gantry on rails and learning a variety of new vulgarities. It helped immensely to have the feedback and advice of two other MK 1 owners in the PNW (KATHY LEE and MONEY SPONGE) who'd also gone through tank replacements recently.
It was an expensive, frustrating, filthy endeavor. Was it worth it? For us it was as we spent four to six months a year for the next ten years cruising with confidence in the systems we installed, not to mention enjoying how much nicer (and quieter) the engine room became after being fully painted & insulated.
Good luck with your decision making,
Vanessa
mvweebles
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Re: Moneysponge, Steve had over $900k in receipts by the time he replaced the tanks, repowered and did Weebles list above, plus more. His wife no doubt named the boat!
After she died it was on the market, at the time I was buying, and even though I knew what he had spent I foolishly I missed the opportunity to buy it. It sold for $325k. Therein lies the rub. If the tanks outboard of the engines leak (and the aft tanks last much, much longer) then either de-commission them and just use the aft tanks. OR, replace the tanks, and do everything else. ie re-power, fit Naiad's etc, etc and then enjoy the boat for 10 years, or preferably longer.
I did the latter, and am now at year 9 and am not selling anytime soon. And Steve's costs were not out of line....
After she died it was on the market, at the time I was buying, and even though I knew what he had spent I foolishly I missed the opportunity to buy it. It sold for $325k. Therein lies the rub. If the tanks outboard of the engines leak (and the aft tanks last much, much longer) then either de-commission them and just use the aft tanks. OR, replace the tanks, and do everything else. ie re-power, fit Naiad's etc, etc and then enjoy the boat for 10 years, or preferably longer.
I did the latter, and am now at year 9 and am not selling anytime soon. And Steve's costs were not out of line....
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mvweebles
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Remember the scene in American Graffiti, the 1972 film about Eisenhower era teenagers, where the chubby geeky guy gets a peek at the blonde through the opera window of a '57 T-Bird? He melts and immediately falls in love.
More or less describes the first time I laid eyes on an OA 50 Mk1.
Ahh....to be young again
Peter
More or less describes the first time I laid eyes on an OA 50 Mk1.
Ahh....to be young again
Peter
tiltrider1
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This is what I have learned from replacing fuel tanks.
1) it’s easier to cut in an inspection port and have the tank coated with epoxy.
2) remove the old tank before you have the new tank built.
3) it’s ok to make the replacement tank slightly smaller if that’s what it takes to fit.
4) some times two smaller tanks work better than one big tank
5) use a tank manufacturer, not a sheet metal shop, discovering a leak 3 years later due to a contaminated weld won’t make your day.
6) don’t buy an old boat unless you know exactly how you can replace the fuel tank.
1) it’s easier to cut in an inspection port and have the tank coated with epoxy.
2) remove the old tank before you have the new tank built.
3) it’s ok to make the replacement tank slightly smaller if that’s what it takes to fit.
4) some times two smaller tanks work better than one big tank
5) use a tank manufacturer, not a sheet metal shop, discovering a leak 3 years later due to a contaminated weld won’t make your day.
6) don’t buy an old boat unless you know exactly how you can replace the fuel tank.
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I suggest using a borescope camera to assess the situation. If they are like mine were then you will see large amounts of flaking rust outboard, next to the hull and on a weld seam or the corner. And I only had slight weeps, and a pinhole in one place.
To try and epoxy coat them in situ will involve a lot of labour, and may not be very effective at all.
Best to remove engines and transmissions, etc and proceed as Vanessa noted above. Thats what I did. With the old tanks out they provide a good template to fabricate new ones. There are curves, sloping bottom etc
If you don't already have stabilisers, then this is the time to do it. Make the side tanks a bit shorter at the forward end so the Naiad's (or ABT Trac) can be fitted in the ER close to the forward bulkhead. If you are concerned about losing range with reduced fuel capacity, you can make the aft tanks larger by having the new ones extend further forward. I did that, and ended up with 1238 gallon capacity instead of the standard 1000 gallons.
All great advice. Think I’m going to try and remove the aft tank and decommission the saddle tanks until such time as I need to do a MOH on engines and pull everything in one swoop. How do you eat an elephant? One bite at a time. So I’m trying to figure out which bites to start with first as I’m on a budget of sorts and want to get to a comfortable confidence with the new boat that provides the range I need in costal waters. Rest will come with time. I have in-laws in the marine industry so I can try to do things closer to cost than most. So we shall see how to goes.
