Another Deck-Off Gas tank Thread

[Kirbyvv]

Ok here's another thread on deck-off gas tank replacement. I'll post some photo's as progress is made. Thanks to info. from George Carter, Frank (Penbroke), Tony, Matty and Mr. Fixall, among others, I think I've got it figured out.

It is a 1978 X-18, with OEM aluminum tank. The original tank cracked last summer along a weld on the top of the tank. We patched it with JB Weld and it made the rest of the season. I don't have any inside space to work on it, so packed it away for the winter until last week.

This past weekend my my buddy Paul and I got it prepped to pull the deck. As he said, it's sad to take a good looking boat and tear it apart, do all this work for something that no-one will see. But at least we won't be smelling gas.

The hardest part was getting too the front lifting eye. I'm not a big guy, but it was a struggle to get up there. This is a foamed boat, and the foam made it too tight. I had to hack chunks of foam out for over an hour, kind of like a coal miner, laying on my side in the ski locker, to have enough room to move my arms to be able to hold the wrench. I'm glad I'm not claustrophibic. This was also the warmest day this year, so it was hotter than %$#@ up there. Once I got to the filler, my shoulder wouldn't go past it, so out I came again to remove it. When I finally got in there and had a big enough hole in the foam hacked out, I had a mind fart and couldn't figure out which nut to put the wrench on. I was just about to climb back out and call Penbroke, when rational thought came back. The lifting eye screwed off nicely, using a piece of rebar from the outside and me with the wrench on the correct nut on the inside.

The most intersting part was, there is no drain hole in the bulk head at the stern end of the tank. I've seen all kinds of threads about how poorly the drail tube is put in, but no drain hole into the area under the floor locker. I wonder how much water is in the foam under the tank???

The firberglass tabs were also interesting. The ones at the front of the ski locker looked like someone stuffed a ball of resin coated glass about the size of a baseball at each front corner. About half the tabs were cracked all teh way through. The other half were so thick and heavy duty, they took alot to cut.

Everything is disconnected, the fiberglass tabs are cut (along with my hands), liftiing pieces all fabricated, etc. The deck is held on with every fourth screw so the deck won't come off during transport. Off to a friends shop, where we will use a fork lift with a 16 foot reach to lift the deck. I'll take photo's for sure.

Sorry for being so wordy, photo's will do the talking from no on.

[Just Say N20]

Well, its begun!

I feel your pain regarding the bow area. I too did the "sideways wiggle" up to the bow of my 18 to tighten the towing eye. One of the most uncomfortable things I have done. I'm not claustrophobic, but I had to have my son sit in the boat and talk to me non-stop the whole time I was up there to keep me focused on something other than where I was.

He had to pull my feet to help me get back out.

The good news is, that with the condition of your boat to start with, you are already in pretty good shape.

Keep the pictures coming.

I was surprised at the weight of the deck on my 16. (4) adults lifted it off fairly easily. I slide a 2 x 8 under the deck at the front of the engine compartment, and another one just in front of the dash. We all lifted and a friend on my garden tractor pulled the boat out from beneath it.

[jl1962]

Crawling under the deck of a classic - now there's something I was born to do! Sorry I wasn't there to help - might get another chance another weekend. Line up some "no experience necessary" tasks and I'll see what I can do.

Glad you got started!

[gcarter]

The only thing that surprises me is the absence of a drain.....but then again, that may not even do it!
If I were you, I'd plan on doing something to replace the tabs. There's lots of options. I mounted Minx tub on some aluminum angles bolted to the stringers. It turned out solid as all get out.
I'm doing the same w/the TR.
Good luck w/the project.

[Kirbyvv]

Figured I might as well do some cosmetic stuff while this project is underway. Just ordered some new decals from Richard Weaver. What a great guy to deal with. I highly recommend anyone needing some decals to contact him.
mine aren't in too bad shape (see photo), but while waiting on the tank I'm going to compound and/or wet sand the hull and deck.

[Just Say N20]

I don't know who Richard Weaver is, or how to contact him.

I need new decals.

Thanks.

[Kirbyvv]

Richard Weaver owns Weaver's Marine in Shapleigh, Maine. He has restored a Donzi 14 and Hornet to better than new conditions. He is a great guy to talk with and has or can get OEM style age appropriate decals. He had the ones I needed in stock. You can contact him at (207) 636-2133. Expect to pay about $100 for entire set, shipped.

[jl1962]

Bill - I got my decals from Richard as well. Great guy.
Jay

[Kirbyvv]

The deck came off yesterday without any major issues. Two men and a three year old. The only issue came when we tried to drive the fork lift with deck out of a 14 foot wide garage door. It took some manuvering and one chip to the gel.

[Kirbyvv]

We also pulled the tank yesterday. It was an FMT-25-DZ , 25 gallon, built in June of 1978. The hull was also built then.
This is a foamed boat, so chopping foam has become my hobbie. It's not to tough, but gets everywhere.
We had pumped the tank as much as we could, stuck a hook in the sending unit hole and made a hook out of rebar for the filler hole. I used a hand saw to saw cut the foam around the tank. The gas smell was a bit too strong to use any power tools. It popped right out, but wow, raw gas and gas saturated foam. There was a few inches of gas beneath the tank. Chopping out the gas saturated foam was a real "blast". The tank looked great except of the crack at the top seam. All this gas had gotten under the tank from that little crack on the top.

[Kirbyvv]

We wrapped the engine in plastic since it was a rainy day and I headed for home with just the hull. All the measurements are done and the new tank will be ordered from FMT tomorrow (5/10/2010). I'll have 4 weeks to chop foam, move a bulk head, clean up the hull, relocate the trim tab pump, add hydrualic lift to the hatch, try and fix some delaminations on the hatch among other things.

[Just Say N20]

Lots of good progress.

Can you figure out what caused the crack in the tank?

That is a lot of gas in the bilge. You would have been more aware of the problem if there had been a limber hole in that bulk head, as the gas ran beneath the cockpit storage area into the engine compartment.

[OFFSHORE GINGER]

Kirbyvv , lookin good and dont you just hate all that foam and just curious are you going to refoam the tank back in because there is a whole lot of other options out there like gcarter suggested .:)

[penbroke]

You're making good progress! Hitting it hard! Have you had that "Oh my god what have I done?" moment yet?

That foam looks like a pain to deal with though. I've been scared twice in my boat. Once was when I was sitting in the open hull scraping out the fuel soaked foam from the tank compartment... Be safe.

Check, adjust, fix, lube, or replace everything in the boat. You'll never have better access. I ran a palm sander over the inside of entire hull to knock down all the sharps sticking up. Not enough to change the lumpy character but just enough so I don't get cut everytime I stick my hand in the dark places. I also cleaned up and painted the area of the hull under the floor storage tub. I leave the tub out and have lots more storage there.


Frank

[penbroke]

...That is a lot of gas in the bilge. You would have been more aware of the problem if there had been a limber hole in that bulk head, as the gas ran beneath the cockpit storage area into the engine compartment.

Boats of that era usually had a drain tube from the bulkhead forward of the tank to the bulkhead aft of the tank. The theory was to confine any fuel leak to the tank compartment and keep it out of the engine spaces.


Frank

[Kirbyvv]

Yes, Frank, after the deck was off and the tank out, I was sitting in the hull saying holy $#%@ what have I gotten myself into. I woke up in the middle of the night dreaming about getting the wiring all screwed up.....

Then yesterday I made good progress chopping out the foam. I'm going to sand the inside of the hull and paint with bilge coat. I'm leaving one section of foam in place. The cockpit sits nicely on it and it does offer some support.

I'm going to foam the new tank inplace, but will have a drain tube beneath the tank from the forward bulkhead to the one at the back of the tank.

I'm relocating the trim tab pump to the engine compartment. it was in the floor locker. I'm going to clean up the wiring as there is old stuff and new. Some just cut off and goes nowhere. I'm also going to add side rails to the deck, since I can access the middle piece nicely.

Tank gets ordered today. I'm ordering the same tank as I have. I can only move the back bulkhead back 3-4 inches and keep the full floor locker and that only gains me about 1.6-2.5 gallons. It's not worth the effort to relocate the bulkhead.

[penbroke]

What is the capacity of your old tank?


Frank

[DON N.]

Kirby said on 1st page 25 gal.

[penbroke]

Thanks Don. I was just double checking because I expected there would be enough room to make the tank 10 -12 inches longer...


Frank

[mrfixxall]

If you made the tank 1'' taller that should be good for a few exrra gallons:)

[Rootsy]

Moved the bulkhead back 12 inches in the Mistress. FMT built my tank design from the blueprint I supplied them. Fits like a glove. Capacity is 33 gallons.

[Kirbyvv]

Rootsy, thanks for the diagram of your tank. If I want to keep full use of the floor locker, I can only go back 3 inches. I might be able to go up 1 higher though.

[Just Say N20]

Make sure you measure the height thing carefully.

I don't remember the fuel withdrawal location on the 18. On my 16 the tank fits fine, but the fitting where you attach the fuel line to the engine sat about 3/8" too high, and it actually wore/bashed a hole through the cockpit floor, right next to where the outer lip of the ski storage trough is.

I'm not trying to be an alarmist, but would hate to have you go to put it together, and run into the same little snag.

[gcarter]

[quote=Just Say N20;565003]Make sure you measure the height thing carefully.

I don't remember the fuel withdrawal location on the 18. On my 16 the tank fits fine, but the fitting where you attach the fuel line to the engine sat about 3/8" too high, and it actually wore/bashed a hole through the cockpit floor, right next to where the outer lip of the ski storage trough is.
[quote]

Bill, follow carefully...remember the deck is a trampoline. It fatigues after awhile. The tabs sag and fail.
The deck is probably 1" or more lower than it was when new.
The solution;
Set the deck on the boat, put two scissor jacks under the cockpit floor and raise it until it is at the height you want it.
Then do the 2" angle routine I did w/the Minx.
You can have the room you need.
PM me if you need more input.
But this works, and fixes a LOT of problems.

[mrfixxall]

I have 2'' of clearance between the tank and the floor from looking at the fuel line/shut off valve hole..If you look at the pic in post 10 he has plenty of room to go higher..

[Just Say N20]

Thanks for the input, for both of us.

George, I plan to do as you said. When I took the boat apart, the only thing holding the deck to the hull were the shoebox lid screws. There was NOTHING securing the cockpit tub to the hull anywhere. That could explain why the tank fitting bashed through the floor. It had to have been flexing like crazy without anything holding it firmly in place.

I hadn't thought that a properly supported cockpit floor would "lift" the whole thing high enough to get the necessary clearance.

I am going to glass the front section with the footwell and ski-storage area to the rest of the cockpit/deck. I see no reason for this to be (2) separate pieces. It had to be made this way from a mold stand point, but once it has been built, is there a reason why I shouldn't glass them together?

Sorry about the hijack.

[gcarter]

I am going to glass the front section with the footwell and ski-storage area to the rest of the cockpit/deck. I see no reason for this to be (2) separate pieces. It had to be made this way from a mold stand point, but once it has been built, is there a reason why I shouldn't glass them together?

I don't know enough about 16's to comment.
But whether you do or don't, do the support thing first so you can have access to the tub bottom w/o the storage locker in place.
Once you get the angles in place, you can do most anything you want.

[Kirbyvv]

The tank has been paid for and I'm waiting on the design sketches to sign off on. Should have them by lunch today.
I remeasured everything last night and still can't get more than a few inches longer without loosing floor locker space. With space at a premium, I want all I can get.
Also chopped out more gas soaked foam forward of the bulkhead at the front of the tank. I didn't have a clue how much gas had spilled when the tank cracked. I don't have a clue why it cracked except that it's 32 years old. The crack was on a weld?
It has become part of my daily routine now, come home, mow the lawn, clean the gutters, etc., then chop foam until dark.

[penbroke]

Just for giggles could you measure the length and width of the tank compartment when you get a chance?


Frank

[CHACHI]

It has become part of my daily routine now, come home, mow the lawn, clean the gutters, etc., then chop foam until dark.

Good thing the sun sets after 8:00 PM. :wink:

Ken

[Kirbyvv]

Frank, the existing tank was 22 x 42 inches. The opening is about 23 1/2 x 43 inches. The lip on the storage locker is 3 1/4 inches behind the the aft edge of the bulkhead aft of the tank. There was only about 1/4 inch between the aft end of the tank and the bulkhead. I'll remeasure tonight if I get home before dark, but it looks like the stringers are 24 inch on center. Could the barrel backs you and Rootsy own have a smaller floor locker, set farther aft???

I confirmed the measurments for the opening, 23 3/4 x 43 1/2 inches.

[Kirbyvv]

I got alot accomplished this weekend and found some more work that needs to be done. I figured that would happen. I got all the old foam out, with the exception of two places where it offers great support for the cockpit floor. Sanded the entire inside of the hull, mainly to get all the foam residue off, drilled the bulk heads for the drain tube beneath the gas tank. drilled beneath the two foamed areas for drain tubes.
But when I pulled the foam from the two sides of the engine, I found some cracking at the end of two of the gussets. Not bad, but...So, spent this afternoon prepping the gussets for some fiberglass work. I figured I might as well do them all, since it's so easy to get to. So I've got a bad case of the fiberglass itch going now and dust everywhere. It was too hot to wear the tyvek suit......I'll post some photos when I get a chance. Gussets and sealing in the drain tubes will be next, then painting the inside of the hull with bilge coat.

[Walt. H.]

Looken good so far!
I never used a tyvek suit just wore a pair of old work coveralls and duct taped the cuffs and ankles and I still sweated a gallon of fluid out per half hr, but heck its the easy way to lose weight w/o trying.:shades:
Plan on buying a another shopvac before you're through if you haven't done so already, fiberglass dust is a muther on them.:yes:

[jl1962]

Kirby-

You are going to be the dustiest person at the Dust-Off! Don't worry about the boat not being ready - you should try to get a ride in one of everything. Kind of like the Donzi version of "hitting for the cycle".

Keep the pictures coming and don't forget the orange and black splatter paint in the bilge.

-Jay

[Rootsy]

Tyvek? You don't want to look like this????? Really, itching is fun.... burns calories....
http://www.jarootfarms.com/photogallery/albums/1966%2018%20Restoration/normal_1966%20C18105%20%28316%29.JPG

[Just Say N20]

Or this?

[gcarter]

Don't you guys ever take showers? :wink:

[mattyboy]

Kirby,
if i could ask a favor can you take a pic of your 280T trim switch and the trim pump for me while you have the top off?

Thanks

Matty

[Kirbyvv]

Matty,
I'll give you the trim switch I just took off. I'm putting a different one on, but neither is OEM. I'm putting a Graffrig throttle mount switch on. it is not designed for the teleflex type throttle, but with a little dremel work, I've got it to fit nicely.
Remember, mine wasn't a 280T from the factory, I bought and added the power trim transom assembly. I went through 3 used volvo trim pumps (they all came with the power trim transom assembly I got from Wayne "onesubdrvr"), before I put in a merc pump. The merc pump is higher pressure, so moves the drive up and down faster than the volvo unit did. If you still want a photo, I can shoot you one.
This is the trim switch I've been using and will give to you. It will mount to any flat surface or to the steering wheel. http://cgi.ebay.com/ebaymotors/TH-Marine-Boat-Steering-Wheel-Trim-Tilt-Control-Switch-/230470286035?cmd=ViewItem&pt=Boat_Parts_Accessories_Gear&hash=item35a9197ad3

and this is what I'm putting on, only for left hand throttle. http://forums.screamandfly.com/forums/showthread.php?t=213713

[mattyboy]

Kirby,
I guess i am trying to get at how many wires are on the circuit.
my boat has the original volvo type switch spdt with 3 wires .
the wires have rotted off the trim pump but what I am figuring is hot, up, and down and there is no "trailer" mode

[Kirbyvv]

I'll take a photo, but I know there are 4 wires going to the pump and I don't have any trailer mode either. I know this because I had to cut them when the deck came off.

[Kirbyvv]

Matty, my mistake, it's a 4 wire bundle, but only three are actually used between the switch and pump.

[mrfixxall]

Matty, does your boat have a 280t?

[mattyboy]

yes, and with all the manuals i have the trim wiring diagram pages are missing :boggled:

[mattyboy]

sorry for the hi jack now we return you to our regularly scheduled thread

how the tank coming along Kirby?

[Kirbyvv]

Made some great progress this weekend. Everything takes longer than anticipated. Glassed gussets, relocated trim tab pump, move wiring around, installed the drain tube beneath the tank and painted the inside of the hull with bilge coat. I had 1 can of white and 1 of gray, so since the engine compartment was gray, it stayed gray and the front of the hull is now white. how many people have a two tone hull???

[Kirbyvv]

and a couple more...

[gcarter]

When I was working on Von Kamps 18, I moved the tank bulkhead aft far enough to install a later model 41 gallon tank.
This boat had the fiberglass drop in cockpit floor storage compartment.
I had plans to shorten the storage tub and extend the forward flange to make it fit normally in the cockpit floor.
I could still do that for someone at a reasonable fee if they wanted it done.

[penbroke]

Looking good Kirby!! You'll be back on the water before you know it.


Frank

[Kirbyvv]

I've been out of town a bunch lately, but the hull is all ready. I was going to move on to some deck work, but the new tank arrived today, a week ahead of schedule. FMT did a nice job. To bad something this pretty is going to be hidden.
So, on to preping the tank George Carter style, 2 part PPG epoxy primer, followed by 2 part coal tar epoxy (George I found a place to by it by the gallon). Now I'm thinking I just might have it done by the dust off????? Too bad work gets in the way. I'll post some more pics this weekend.

[penbroke]

...Now I'm thinking I just might have it done by the dust off????? Too bad work gets in the way...

The way I heard it you make the rules at work. Git 'r done! :wink: :wink:

See ya soon...
Frank :cool:

[Kirbyvv]

OK, I got a bunch more done, but she won't be seeing the Dust-Off. Primed the tank with PPG high chromate epoxy primer. This is nice stuff as there is no sanding necessary. Then did the coal tar epoxy. Boy is that thick stuff.
Then while waiting for the epoxy to harden I added a trim switch to the throttle. I had the switch for the Volvo 280T on the steering wheel, but wanted something I could use without looking. This Gaffrig left hand unit was on sale for $20. It was made to fit a flat throttle, so I had to do some grinding and shaping with the trusty dremel. Also updated and replaced some wiring while it was easy to get at.

[Kirbyvv]

I added side rails today also. I put painter tape on the deck so I wouldn't scratch it. Mocked it up, drilled all the holes, then pulled the tape, waxed the H&%$ out of it and put it back together. I used Bill's method and epoxied a stainless T nut for the center bracket. It took longer than anticpated, but no scratches.
Actually waxed the whole deck. It was way easier with the deck only 4 feet off the ground.
Hopefully if the weather holds, I'll get set up for foaming the tank tomorrow.

[Just Say N20]

Kirby, most excellent job! Very well done, and the deck looks awesome!

[Greg Guimond]

Kirby, while that deck is off get a scale under it to see what it weighs in at. I wonder what it is as compared to a 16.

[Kirbyvv]

I don't think my bathroom scale goes that high.....I can pick up one end by my self, but it's not light.

[Kirbyvv]

The tank is in place, blocked, clamped, etc. Weather permitting I will foam it in tomorrow night. Progress is a good feeling.

[gcarter]

Excellent Kirby!

[Sweet Cheekz]

Looking great Kerby!
Parnell

[MOP]

Nice it sure looks like you have covered all the bases, soon it will come alive and make noise!

[Kirbyvv]

The tank is in, wiring done and gas line goes on today....Drum roll..the deck goes back on tomorrow. I see the light at the end of the tunnel now.

[Kirbyvv]

The deck is back on finally. Actually we put the deck on twice today. First I put a bead of 4200 around the lip of the deck, then lifted it and set it with a track mounted boom. it slid right on. We put all the screws back in and then I climbed in to find the wiring harness had slipped and was pinche between the front of the cockpit floor and side of the hull. So out came all the screws and off it came again. Now to move the wiring harness I ended up covered with 4200. Real nice stuff to have in your hair, face, clothes. But in the end she is back together and in the driveway. I still have a bunch to do, but big time progress. It's a good feeling.

[axelkloehn]

you're going strong, man! Good job!

[Kirbyvv]

FINISHED:rlol:
Marathon session on Saturday. I haven't put it on the hose or anything yet, but there are no parts left over!!!!

[jl1962]

:crossfing:

[gcarter]

Congratulations!

I always have lots of leftover parts.....like every original fastener in the boat.

[CHACHI]

Kirby, congrats.

Now you owe me a ride at Americade next year.

Hope to see you in August.

Ken

[mike o]

FINISHED:rlol:
Marathon session on Saturday. I haven't put it on the hose or anything yet, but there are no parts left over!!!!Hey, way to go......... now enjoy.:wink:

[penbroke]

Good job man! Once you get on the water let her strech her legs a bit you'll feel this little smile inside and realize it was worth all the effort. She is no longer what's his names old boat. She is now yours...


Frank

[Sweet Cheekz]

Well done Kirby
It seems llike it went fast to me so let us know how it works out.
Parnell

[DON N.]

It looks like the job came out execellent , very nice work !
Also , thanks again at lake george .

[Tony]

Congrats, Kirby!

Tackling this project is a daunting experience, especially so if you've never done anything like it before. All of which makes completing it successfully even more rewarding. Nice job!


:)

[Wet Vette]

I'm about to separate my deck and replace the tank. Where did you buy your tank and do you have a drawing of it? Gallons?

[Tidbart]

[ QUOTE=$originalposter]{$pagetext}[/QUOTE]

He used a slightly modified, 25g, FMT (Florida Marine Tanks) tank. Original manufacturer. Later 18s used a 41g model.

Bob

PS, You can start your own thread on your project, makes it easier to track.

[Kirbyvv]

Yes, that is correct. I pulled the original Florida Marine Tank (FMT) info off the tag, and they still had the drawings. I did have the pick up and sending unit moved so they were directly below the floor access port. It is 25 gallons. I'd like a larger tank, but didn't want to loose any storage capacity in the floor locker.

[scippy]

Kirby,

A question about the fuel tank prep if you don't mind. Got the coal tar epoxy already. Where did you buy
and how much did you use of the high chromate epoxy primer on your single 25 tank?....I noticed you
painted every side but the top. Mine are (2) belly tanks 60" long and are 60 gals apiece. Also, what type
of foam? closed cell?? ...what weight?......................Thanks

[Wet Vette]

thanks for the information. I think I want to go larger even if I lose some storage. I'm lifting the deck in the morning.

[gcarter]

Pete; this is the foam I used;
http://www.shopmaninc.com/foam.html

I reccomend the 4 LB density foam in the 16 LB kit. catalog #0416. Four LB is what's reccomended by the marine industry. It's pretty tough.
What you get is two (2) one gallon cans of two part foam. Each kit will make quite a bit of foam, but it takes a lot.
On the Minx I used one of these kits (47 gallon tank), but the TR's 62 gallon tank required more than one.......I used one, but I had to re-order an additional smaller kit to finish.
Bummer!
I would reccomend you start w/two of the #0416 kits and another smaller kit, just to make sure.

Yeah, I know my name's not Kirby........

[scippy]

George, thanks for the foam info!......Should the gas tanks sit flush upon the bottom?
I already glassed in the drain tubes, and wondered if the tanks should just lay flat on
the glass hull & just pour the foam around the whole inside perimeter?.....of course
with the clamps in place.

[gcarter]

Pete, I think you'd be better off wedging the tank into place w/the tank bottom clear of the hull.
I had some little tabs welded onto my tank so I could suspend it above the bottom. Since it seems you haven't finished your tanks yet, it's not too late to do this (I sawed them off later).
Something else to consider, is when the foam gets under the tank, it'll have maybe a couple of hundred pounds of lift while it's expanding. You have to come up w/some plan to retain the tanks.
I bolted some 2" X 2" x 1/4" angles to the stringer tops and clamped 2" X 4"'s accross the angles and the tops of the tanks to retain them.

[scippy]

George,

How much space is ideal to have between hull & tank bottom for proper foam penetration?
I have plenty of vertical play with the tanks so no problem there plus, I do have aluminum tabs
that the tank mfg. welded on for me (2 each side & one each end) I will also brace the tanks
from pushing w/clamps and 2x4's........One last thing concerning pouring, is there enough time
for the foan to get fully under the tank before it "kicks"........I'm thinking "fast -n- furious"

[Tidbart]

Just something else to consider..... leave enough room on the top of the tank so you can access the sender and fuel outlet through the inspection plate after the deck is replaced.

B

[gcarter]

Pete, probably 1" average space is good.
Initially, it'll expand a lot slower than you would think.
This is 4 LB foam, it doesn't expand as much, that's how t hey get the density.
It'll take longer than you think untill it all starts heating up, then it goes faster.
By that time, the bottom is full and it starts filling the sides.
So, if the aft end is lower (usually the case), start at the rear.
I masked off the top of the tank and stringers, and worked on top of it, i.e., I had my foam cans, two 1 Pint, or quart mixing cups, and one 1 gallon mixing cup (but you'll need several of the large cups), a bunch of rubber gloves, all on top of the tank.
Find a somewhat comfortable position for your old body to spend some time in, pour identical amounts of part "A" and part "B" into the two smaller cups (don't get them mixed up) and then into the large cup, mix w/a stir stick and pour around the rear of the tank.
After it's mixed in the large cup, don't expect much to happen......just pour it into the space. The lowest space under the tank will expand first. Maybe you'll go a little slower to begin with, you may not want too much going on until it starts heating up. I'm not saying wait a long time between pours, just keep moving at a reasonable somewhat slow pace.
After about 3 or 4 pours out of the large cup, expanded foam will start filling it, as soon as that happens, start on another large cup.
Like me, you've got some fairly large tanks, stay on top of what's going on, keep it filling evenly.
Not only does it not expand real fast, it expands for a fairly long time. It's hard to gauge when you've filled enough around the perimeter and expect most of it to overfill. Be prepared to trim it the next day or so.
Also, I'd suggest not trying to set both tanks in one day, I think you'll find it a lot more emotionally exhausting than you might think.

[scippy]

Thank you guys (Geoge and Tibart) no excuses now, if I screw this up can't say I wasn't completely informed.
What's the deal with all the foamed in "saturated" tanks of the past....was there no closed cell foam back then?
I know inproper drainage would swamp a tank, but would that still occur with cc foam?.........thanks Scippy

[gcarter]

The tanks weren't coated in any way.
They never stood a chance.

I once figured the cost in doing it correctly from the beginning would have been maybe $10.00 extra per boat.

[Morgan's Cloud]

Just to add a few more thoughts if you haven't already started .
Phil advised me (when I was doing mine a few years back) to do a 'sample mix' first. I used an old plastic coke bottle with the top cut off.
I'm glad I did as it gave an excellent idea of what type of yield I would get with different sized batches.

For months before I did mine I was hoarding 1.5 gallon bleach bottles (tops cut off) for my mix/pour containers. You have to use a new container for each batch so you'll need plenty.

You'll find that once you start stirring the two ingredients the colour of the mix quickly changes. Once that happens you have to move fast. If you keep stirring just a bit too long , it's too late. Especially if you're working in very warm ambient temperatures. You have to pour the mix while it's still a liquid and it doesn't take long for it to fire off and start foaming !

[gcarter]

What Steve said is correct, as there'll be differences between envirtonmental conditions, and foam providers.
Apparantly the foam he was using sets off a lot quicker than the foam I got from U.S. Composites.
Best to make sure.

[mike o]

4lb is a structural foam, it expands slower than 2 which a flotation foam. You mix by weigh not volume. B side is lighter so mix 52% B to 48% A, above 75 degrees. Take 2 equal plastic spoonfuls and mix into a Dixie cup to get a feeling for the timing + growth. You must mix them throughly for the chemistry to work. The bigger the batch, the more heat it generates in the cup and so it will react faster. Wait 5 minutes between pours so the early stuff gets stable... :)

[Kirbyvv]

I've been on vacation and away from the computer. I used George's recommendations for my entire project. He was a great source and his thread on the Minx tank was my bible. I used a few pieces of scrap foam from when I pulled the old tank to position the new tank before the pour. I also had the tabs on the tank, so the tank was bolted in place and clamped and blocked the tank (see previous photos) to prevent the foam from lifting it even though it was also blted in place.