New project with a bladder problem......

[Bigbore500r]

*EDITED WITH PICS*

Im taking on a new-to-me boat project, a 10M Cooper Prowler "aft cab" that is currently slipped in Channel Islands Harbor. Nice boat, great condition and runs well, but it has deteriorating aluminum tanks that are not flushable / fixable in any manner. One of the tanks actually began seeping into the bilge and they were both drained and dryed out as a precaution. The tanks are completely un-accessable without major demo work, cutting the gunnels open and ripping the interior of the boat apart. The plan is to leave those tanks empty and abandon them, and run a new tank or fuel bladder setup to get this boat back on the water. The boat runs great (when the carbs arent contaminated with tank sediment...) and overall is in good shape, it's a shame that the tanks took it out of service. So i'm gonna fix it.....

Thinking of either having a few new tanks made custom to fit in some alternate locations in the bilge, or possibly even on the lower back patio deck and built in to a sort of "bench seat" that would conceal them. These ATL fuel bladders look pretty cool, wondering if I can build a deck box of sorts and have one made custom sized to fit in the box. They seem to be made well and from what I can tell are USCG legal for use above deck.

Photos of similar boat - 10M cooper prowler "aft cab" with 2 staterooms and 2 heads, central galley / saloon layout.

Tons of room on back deck to place a bladder / tank setup and make a deck seat out of it. 6' wide x 2' deep x 18" high would get us 130 gallons or so, and we could always have another bladder for extended range. This thing is gonna be used for harbor cruising and a trip to Channel Islands / Catalina at the most, so range doesn't need to be much.

Pic / example of fuel bladders available - can be customized to space and capacity

Theres also room in the bilge forward of the engines, if I relocate the black water tank a bit. But now were moving stuff, putting in support structure, and below bilge ventilation and fill becomes an issue we would need to ensure is safely handled. Above deck seems easier. Weight of tank with fuel is approximately 800lb filled, not to concerned as the rear patio is built like a brick shithouse and the boat weighs in at 15,000lb! It's not gonna notice the weight of 3 men on deck.



The thought is to build a deck box (a very sturdy deck box) that appears to be a built-in bench seat, and under the flip-up lid is the fuel bladder that sits inside. Box would be ventilated of course.

Flame away......feedback is appreciated

 

[HCP3]

Can't flame if we can't see the pics.

 

[LargeOrangeFont]

Can't flame if we can't see the pics.

Nor can we flame with dry fuel tanks.

 

[DRYHEAT]

I can’t see the pics either, but the only concern I would have would be raising the center of gravity and altering the balance of the boat. Not sure if this is even a concern depending on how tall the boat is.

 

[Waterjunky]

One of your biggest issues is going to be the change in the center of roll. This is a serious issue in salt water as most fresh cannot generate the waves to really cause a problem. There are exceptions of course.

I am not saying don't do it, just think this through.

Can the existing tanks be cut open for inspection? A possible thick liner installed? This method would keep everything "as engineered".

 

[Taboma]

One of your biggest issues is going to be the change in the center of roll. This is a serious issue in salt water as most fresh cannot generate the waves to really cause a problem. There are exceptions of course.

I am not saying don't do it, just think this through.

Can the existing tanks be cut open for inspection? A possible thick liner installed? This method would keep everything "as engineered".

I agree, adding that much weight on top of an aft cabin will certainly make what tends to be a top heavy boat, even more so. Especially considering most passengers when seated outdoors will be up on the upper level larger bridge area.
I couldn't see the OP's pics, but this appears to be a 35' Prowler as the 32' seems to be called a 9M.
The boat also has a shallow draft and gas engines, which won't aid in stability. With a 12' 6" beam, the engine room pictures I could find seems to provide a fairly wide area between the engines. This area is normally accessible through removable floor sections in the salon. I'd consider having a custom belly tank (Or two) made for that area covered with a plywood top to allow continued access between the engines.
Between condensation and now ethanol fuel causing water to form at the bottom of aluminum tanks, these leaks from the inside out and are becoming more problematic and common.

 

[C08H18]

i would remove the existing swim platform and build a hull extension in place of the platform. The added weight would sit at the water line (partially below, partially above). I did this with a 50' ocean alexander to gain 600 gals of fresh water.

If you really think 800 lbs won't be felt, fill a couple of 5 gal buckets with water and place along the gunnel. IMHO, 800 lbs is a tremendous weight and will cause issues at sea.

 

[Bigbore500r]

Can't flame if we can't see the pics.

Added pics to OP
Oops!

 

[MK1MOD0]

Weight should be placed as low as possible. Think ballast. That amount of weight in the keel could actually help stabilize the boat, but the further up ya go, you get the opposite effect.

 

[Bigbore500r]

i would remove the existing swim platform and build a hull extension in place of the platform. The added weight would sit at the water line (partially below, partially above). I did this with a 50' ocean alexander to gain 600 gals of fresh water.

If you really think 800 lbs won't be felt, fill a couple of 5 gal buckets with water and place along the gunnel. IMHO, 800 lbs is a tremendous weight and will cause issues at sea.

Im not saying 800lb wont be felt, but saying its a 15,000lb boat with a 12 1/2' beam. I know when we put 6 people on the back patio the boat doesn't really notice, nor does it seem to notice 4 people up on the flybridge while underway. But of course it has an effect, its math and physics.

Bilge is better of course. I need to go look at it and take measurements and see what I can do

 

[coolchange]

I think I'd be looking at cutting the old tanks open and adding bladders. As long as they are still structurally sound.
We hang out at CI a lot. Dinner / booze cruzn.
C I to Santa Cruz is what you want!

 

[Bigbore500r]

Went and looked at the boat today. Here are my thoughts -

The area between the motors, forward of the batteries, has plenty of room to house a belly tank. The issue I see is that putting a tank there blocks access to the starter on the Starboard side engine, and in general would prevent you from comfortably kneeling down below deck to work on the motors. There are "hatches" in the floor that open up, but the entire floor above the motors does not open so your would be pretty uncomfortable if you were kneeling on a fuel tank and had to slither under the floor to try and work.

There are 2 other spots that looked good for tanks:

1. Below the bed in the forward cabin (flat on the keel of the hull, toward the front of the boat). Would be easy to throw a 75-100 gallon tank up there. This is pretty much unused space, empty.
2. Below the bed in the aft cabin (next to the fresh water tank, almost center of hull, able to mount 12' away from bottom of bildge on top of existing bulkheads). Easy 75 gallons or so available here.

Now the question is - can you safely install 2 tanks under the beds, with proper venting and fill hose configurations? In my eyes, it is no different than the current tank setup - both of these areas adjoin the bilge at some point, and the current tanks are located in the gunnels on either side of the motors mid-ship. The bilge is directly below the saloon, and while there are hatches to close it off it is by no means sealed airtight. Seems you have the same venting concerns there, and fumes would enter the passenger compartment if not properly ventilated. Could I run a tank under the beds, 1 front and 1 back, and perhapse run added bilge blowers to these compartments to promote ventilation prior to starting the boat?

Using the under-bed areas would put 400lb's of fuel in the nose, 400lb in the stern, pretty much on-centerline of the keel and with the weigh kept as low as possible.

If I need a stern talking to (get it.....) please school me

 

[AEA]

How about contacting the manufacturer, explain the situation and see if they will provide some input on what they think possible solutions might be. It’s possible they would offer some help to point you in a safe direction. Interesting challenge, good luck with it.

 

[lbhsbz]

I wouldn’t concern yourself with fumes or venting...if the tank is properly vented using hoses to outside the cabin, there should be no fumes inside and the only reason to run blowers would be as usual to vent the engine room. Use good gaskets and check them and the fittings regularly and you should be good.

 

[4Waters]

Can you get at the original tanks enough that you could get a bladder in those?

 

[Big B Hova]

Just say no to salt water

 

[Bigbore500r]

Can you get at the original tanks enough that you could get a bladder in those?

Original tanks are trapped in the gunnels. You'd have to yank both motors / transmissions, tear out interior of saloon, tear out flooring...etc etc

 

[4Waters]

Original tanks are trapped in the gunnels. You'd have to yank both motors / transmissions, tear out interior of saloon, tear out flooring...etc etc

Find a different boat

 

[motormonkey]

Nice boat. I knew a guy with a Viking that had an exhaust / water leak. The boat yard went thru the transom to fix. He also had something done to the front state room, they went thru the deck. I asked what happens when a engine goes out. Haha I allready knew the answer. It was then I realized that I had no business or money to own ocean going craft.
With that encouragement, talk to a boatyard and see what they recommend.

 

[Bigbore500r]

Find a different boat

Si Se Puede!
It's gonna get fixed

 

[Bigbore500r]

Nice boat. I knew a guy with a Viking that had an exhaust / water leak. The boat yard went thru the transom to fix. He also had something done to the front state room, they went thru the deck. I asked what happens when a engine goes out. Haha I allready knew the answer. It was then I realized that I had no business or money to own ocean going craft.
With that encouragement, talk to a boatyard and see what they recommend.

Boatyard says 20k and it's good as new ....they want no part in backyard redneck engineering

Hell now that you mentioned it....how DO you get the motors out above floor and out of the Saloon ?
Good thing they're good ole 5.7 SBC's.....sons of bitches better live forever!

 

[chvynhra]

Can't you get the tanks coated while still in the boat?

 

[motormonkey]

Yeh owning large vessels the saying goes break out another 10,000 for everything.
LOL

 

[GRADS]

I'm not sure if I understand what some people are saying will be a weight problem... What would be the difference than running the boat very low on fuel and having 4 fat chicks on the deck?

 

[lbhsbz]

Original tanks are trapped in the gunnels. You'd have to yank both motors / transmissions, tear out interior of saloon, tear out flooring...etc etc

If you hauled it out, cutting holes in the sides to drag out the tanks and glassing everything back up after replacing them probably isn’t as much work as fiddle fucking with it trying to make something else work.

 

[motormonkey]

It's been mentioned allready. Cut a access hole in the tops of tanks and lay a bladder in if possible.
As far as redneck style fixes, just remind the boatyard on how southern shipments get here with 55galllon drums of fuel with dip hoses on the decks. Haha

 

[ka0tyk]

Boatyard says 20k and it's good as new ....they want no part in backyard redneck engineering

Hell now that you mentioned it....how DO you get the motors out above floor and out of the Saloon ?
Good thing they're good ole 5.7 SBC's.....sons of bitches better live forever!

I knew someone that carrieda short block in a cart into his boat as it was docked. Then the heads, etc etc. just did it in pieces. All though an access hatch in the floor of the interior. It can be done...

 

[lbhsbz]

Or...build a bracket...hang a couple outboards off of it. Spend a day down below chopping up the existing engines with cutoff wheels and throw the chunks overboard...then put some tanks where the engines used to be.

inboards are stupid unless it’s under 20ft or over 40

 

[GRADS]

I'd cut the stern off and make a bar out of it for next to my pool...always wanted to do that.

 

[Bigbore500r]

Can't you get the tanks coated while still in the boat?

No. Tanks are leaking, cannot be coated / cleaned. Pinholes and corrosion

 

[Bigbore500r]

I'm not sure if I understand what some people are saying will be a weight problem... What would be the difference than running the boat very low on fuel and having 4 fat chicks on the deck?

Remember that RDP members never have ugly girls on the boat, pay cash for everything, and tow it with a 450 Platinum.

 

[rrrr]

Nice boat. I knew a guy with a Viking that had an exhaust / water leak. The boat yard went thru the transom to fix. He also had something done to the front state room, they went thru the deck. I asked what happens when a engine goes out. Haha I allready knew the answer. It was then I realized that I had no business or money to own ocean going craft.
With that encouragement, talk to a boatyard and see what they recommend.

Back in the 90s, a friend of mine owned a Viking 55 he bought new. Two years after he bought it, there was a defect discovered in the 6 cylinder diesel engine blocks that was terminal. The issue was covered under warranty, but the fix was ugly.

The furnishings in the saloon were removed along with the rear sliding glass door. The saloon was above the engine room, and the floor was cut out to get access to the engines. After the engine room was stripped of all piping, electrical, etc., the engines were rigged out of the boat and new ones were installed.

Returning the engine room and saloon to their original condition was a huge task. I saw the boat just after the new engines were installed, it looked like a bomb had gone off in the saloon. The entire project consumed over a year. I have no idea what it cost, but there was talk of sending the boat to the wreckers instead of repairing it.

 

[gqchris]

Hell now that you mentioned it....how DO you get the motors out above floor and out of the Saloon ?
Good thing they're good ole 5.7 SBC's.....sons of bitches better live forever!

You are a brave man for taking on an ocean boat project. One of my buddies use to own a repair shop for dockside stuff. I helped him often.

To answer your question how to get motors out, its piece by piece! I did it many times. It sucks and most of those ocean boats did not design for any sort of maintenance. We called it "Bilge Yoga". Fuck me I could not crawl in a bilge now, my back would straight give out! LOL

Here is a pic of my most recent Ocean Cruiser. was a great boat, but you have to be prepared for the bleeding! I think my Ferrari was cheaper monthly. LOL

 

[rivermobster]

Now lemme get this straight...

The guy that's always bashing on my 7.3 (that runs perfect by the way)...

Is gonna try and restore a boat, that should have went to the scrap yard????

Classic. lol!!!!!!




A free boat, will be the most expensive boat you'll ever own

-wiseman

 

[Royally PO'd]

The way some of this advice is going, you might think of just towing a dink as a fuel tank...LOL My opinion ( worth $.10), is to figure out where you can put new poly tanks , safely and do good venting,,,, Not in engine bilge, no sweat for fire. If you are using the blowers, it will pick up the whole under sole bilge , anyway... Keep us nosy bastards informed...good luck

 

[Bigbore500r]

You are a brave man for taking on an ocean boat project. One of my buddies use to own a repair shop for dockside stuff. I helped him often.

To answer your question how to get motors out, its piece by piece! I did it many times. It sucks and most of those ocean boats did not design for any sort of maintenance. We called it "Bilge Yoga". Fuck me I could not crawl in a bilge now, my back would straight give out! LOL

Here is a pic of my most recent Ocean Cruiser. was a great boat, but you have to be prepared for the bleeding! I think my Ferrari was cheaper monthly. LOL

View attachment 919000

It's a calculated risk....lol

My buddy has the boat already, and it was a good running boat up till a year ago when the tank issues became unbearable. I'm not buying it, but im taking on the task of fixing it and once done we're gonna split the slip fee and use it as partners.

We can always scrap it if it becomes a bitch down the road lol

Your old boat looks similar to my buddies Bayliner Cierra 3055. We had Menace Marine repower it with twin EFI Merc 377's....been dialed in ever since! He keeps it in the water down in Huntington Habor

 

[Bigbore500r]

The way some of this advice is going, you might think of just towing a dink as a fuel tank...LOL My opinion ( worth $.10), is to figure out where you can put new poly tanks , safely and do good venting,,,, Not in engine bilge, no sweat for fire. If you are using the blowers, it will pick up the whole under sole bilge , anyway... Keep us nosy bastards informed...good luck

That's exactly the plan!

 

[Bigbore500r]

Now lemme get this straight...

The guy that's always bashing on my 7.3 (that runs perfect by the way)...

Is gonna try and restore a boat, that should have went to the scrap yard????

Classic. lol!!!!!!




A free boat, will be the most expensive boat you'll ever own

-wiseman

Lets get this straight.....

Yore a mechanic, and yore saying replacing a fuel tank is too difficult and we should scrap a nice boat? Lol

FYI - I like 7.3's, but the tales of stock 7.3 trucks towing 15k uphill at 80 may qualify as biden campaign material

 

[Bigbore500r]

Or...build a bracket...hang a couple outboards off of it. Spend a day down below chopping up the existing engines with cutoff wheels and throw the chunks overboard...then put some tanks where the engines used to be.

inboards are stupid unless it’s under 20ft or over 40

Somebody should tell every cabin cruiser ocean boat builder since the beginning of time that....

 

[rivermobster]

Lets get this straight.....

Yore a mechanic, and yore saying replacing a fuel tank is too difficult and we should scrap a nice boat? Lol

FYI - I like 7.3's, but the tales of stock 7.3 trucks towing 15k uphill at 80 may qualify as biden campaign material

Well...

Apparently the guy that unloaded it on you thought so! lol

A stock 7.3 can barely get out of it's own way. Ask me how I know...

 

[C08H18]

I have an somewhat qualified opinion...from owning 3 saltwater boats. 38' Californian Trawler, 40' Ocean Alexander, 55' Ocean Alexander.

I would have no issue fixing that boat. you get a lot of boat that others won't touch. i like your two ideas for placement.

IMHO, a poly tank between the motors would be ideal. Design the tank so it could be emptied and lifted if need be and keep the battery cables away from it. how often will you replace the starter? or spend much time down there beyond checking oil levels or pumping oil during an oil change.

Under the cabin beds would allow you to control the fill levels in each and possibly change the ballast and weight. I carried 1200 gals and would often would pull from one tank to change how it would lay. And i would routinely polish fuel between tanks with a extra set of filters and pump. Not something you need to do with gasoline though. The ventilation in the bilge should be adequate too. Ideally the ventilation keeps the bilge slightly under a vacuum and an odor pulled from under the berths.

 

[Bigbore500r]

Well...

Apparently the guy that unloaded it on you thought so! lol

A stock 7.3 can barely get out of it's own way. Ask me how I know...

My initial investment is limited to tanks, brain power, elbow grease and splitting the slip fees. My friend has the boat already, i'm not buying it, im just captain save-a-boat

The plan is that it's all sunshine, BBQ's and high fives from there on out.....yea, that's how its supposed to go!

If we get a working boat out of it, and he has a partner that can turn a wrench and save him from the harbor rapists (oops...meant mechanics) its a win-win

 

[Gonefishin5555]

My fishing buddy brought the tanks back to functionality on his late 70s uniflite. He cut a 12 inch circle in the top and I'm not sure what he used to coat the inside or how he sealed up the cutout. Its been about 10 years without any problems. I'll ask him next time I fish with him but I remember him contemplating a very difficult and expensive repairs if his quick fix didn't work.

 

[rivermobster]

My initial investment is limited to tanks, brain power, elbow grease and splitting the slip fees. My friend has the boat already, i'm not buying it, im just captain save-a-boat

The plan is that it's all sunshine, BBQ's and high fives from there on out.....yea, that's how its supposed to go!

If we get a working boat out of it, and he has a partner that can turn a wrench and save him from the harbor rapists (oops...meant mechanics) its a win-win

I've met your crew. Hard to go wrong with that group!

Good luck my friend. Me thinks your gonna need it!