Floor replacement question

[62cruiserinc]

Re: Floor replacement question

Two quick fuel tank questions:

1)To flush out the tank properly, I will have to remove the sending unit as that has the largest hole through which I can check out the tank and pour cleaner in/out. The gasket will probably have to be replaced. Are sending unit gaskets still available for 1984 boats or do I get some gasket material and cut my own?

2) In several articles I have read about gas tank installation, they have mentioned not to have the tank supported by the hull. In my boat, the tank was originally resting on the hull (with rubber strips under it). Because of the shape of the tank (V-shaped bottom) it appears that the tank has to be supported by the hull to fit in the available height. I can't simply attach pieces between the stringers to support the bottom of the tank because the bottom of the tank is below the bottom edge of the stringers. Is it ok to reinstall the tank as it was originally put in (laying on strips attached to hull)?

Thanks
Steve

 

[62cruiserinc]

Re: Floor replacement question

Any suggestions on the fuel tank questions?

I am open to any input.


Steve

 

[jbcurt00]

Re: Floor replacement question

There have been a few threads discussing keeping the hull up & off the hull to allow any water under the tank to escape & not promote corrosion. Friscoboater Jay used a recycled tire door mat from wally world. Other people have used other types of 'shim' to elevate the tank. Maybe these will help:

Aluminum tank installation1

Aluminum tank installation2

Barato2 has a post about the gasket material, but I can't seem to find it..... But you can hit him W/ a PM or find a post of his, click his user name & scan thru his last 500 posts or his boat threads looking for it.... An advanced search may find it.....

 

[62cruiserinc]

Re: Floor replacement question

Thanks for the info, jb.


Steve

 

[62cruiserinc]

Re: Floor replacement question

I'm getting closer to the actual installation of the stringers. The bulkheads have been cut to size and only need the fuel line cutouts along with the bottom cutout to allow water to flow down the center of the bilge.

I have a few questions:

1) Is one layer of CSM (after the resin soak) enough to waterproof the edge of the bulkhead cutout that is exposed to the water in the bilge?

2) For those who used PL for stringer bedding, did you have a problem with wiping off the excess PL without getting it all over the hull and stringer side? I am assuming that PL smeared on the hull and/or stringer would affect the bond of the PB fillets and tabbing.

3) For those who used PB for stringer bedding, did you apply the PB first and then drop the stringers into the PB, or did you suspend the stringers 1/4" above the hull and then apply the PB under the stringer bottom edge? I am concerned that I wouldn't be able to force the PB into the 1/4"" high space (my stringers are 1" thick). If I put the PB down first I don't know If I would have enough time to align the stringers and bulkheads before the PB kicked off.


Thanks
Steve

 

[Woodonglass]

Re: Floor replacement question

I'm getting closer to the actual installation of the stringers. The bulkheads have been cut to size and only need the fuel line cutouts along with the bottom cutout to allow water to flow down the center of the bilge.

I have a few questions:

1) Is one layer of CSM (after the resin soak) enough to waterproof the edge of the bulkhead cutout that is exposed to the water in the bilge? Not sure I understand "Edge exposed to water"???

2) For those who used PL for stringer bedding, did you have a problem with wiping off the excess PL without getting it all over the hull and stringer side? I am assuming that PL smeared on the hull and/or stringer would affect the bond of the PB fillets and tabbing. When using PL I suspend the stringer with 1/4" dowels and put about a 3/4" bead of PL down and set the stringer trying to not get to much squeeze out. Just want it to act basically as a rubber gasket between the hull and the stringer. 72 hours later PB the fillets.

3) For those who used PB for stringer bedding, did you apply the PB first and then drop the stringers into the PB, or did you suspend the stringers 1/4" above the hull and then apply the PB under the stringer bottom edge? I am concerned that I wouldn't be able to force the PB into the 1/4"" high space (my stringers are 1" thick). If I put the PB down first I don't know If I would have enough time to align the stringers and bulkheads before the PB kicked off. Same with the PB as PL, Bead of PB to set the stringer but good thing is you can immediately begin filleting.


Thanks
Steve

See answers above.

 

[tpenfield]

Re: Floor replacement question

Two quick fuel tank questions:

1)To flush out the tank properly, I will have to remove the sending unit as that has the largest hole through which I can check out the tank and pour cleaner in/out. The gasket will probably have to be replaced. Are sending unit gaskets still available for 1984 boats or do I get some gasket material and cut my own?

2) In several articles I have read about gas tank installation, they have mentioned not to have the tank supported by the hull. In my boat, the tank was originally resting on the hull (with rubber strips under it). Because of the shape of the tank (V-shaped bottom) it appears that the tank has to be supported by the hull to fit in the available height. I can't simply attach pieces between the stringers to support the bottom of the tank because the bottom of the tank is below the bottom edge of the stringers. Is it ok to reinstall the tank as it was originally put in (laying on strips attached to hull)?

Thanks
Steve

I recently installed a new tank in my Formula 242 . . . so here are my words of wisdom on the subject . . .

If the sender is the 'standard' 5 bolt pattern, then you should be able to get a suitable gasket replacement.

The main concern about fuel tank installation is to adequately support the tank. Keep in mind that the fuel in the tank is 8 lbs. per gallon (+/-) so a 50 gallon tank would be about 400 lbs, plus the weight of the tank. Neoprene strips will keep the tank suspended off of the hull to avoid direct contact. In your installation, that is what the strips were for . . . keeping the tank from direct contact with the hull. So, yes, you could replicate the original OEM installation as long as the isolation from the hull is adequate and the fastening is adequate as well.

Many boat manufacturers foam in their tanks because it is the best overall method of suport and strength. . . I contacted Formula Tech Support about this for my boat, and they confirmed that they still foam in their tanks.

The problem with many OEM installations is that they do not provide drainage from under the tank. So, moisture does collect in the tank bay, and it has no where to go. It eventually saturates the foam and comes in contact with the aluminum surface of the tank, causing it to corrode. If you provide drainage from the fuel bay, you will be miles ahead.

 

[62cruiserinc]

Re: Floor replacement question

WOG: I was referring to the edge of the bulkhead where the "water flow clearance" cutout is in the middle bottom. Normally this cutout allows bilge water to flow underneath it but if the bilge were to fill up it would eventually touch this edge.

tpenfield: My tank is a 28 gallon aluminum tank. I will space it with the strips to keep it off the hull, but the weight of the tank and gas will still be borne by the hull. I don't have an alternative as there is no room to build a "false bottom" to allow the tank weight to be supported by the stringers. There is very little room around the perimeter of the tank (less than 1 inch at the ends, 1/2" on the sides). It was supported only by the rubber strips on all sides, including the top. There isn't much room for foaming it in.

Steve

 

[jbcurt00]

Re: Floor replacement question

WOG: I was referring to the edge of the bulkhead where the "water flow clearance" cutout is in the middle bottom. Normally this cutout allows bilge water to flow underneath it but if the bilge were to fill up it would eventually touch this edge.

Some slice thru a pvc sch40 pipe & set it w/ 3m 5200 into the water clearance opening:

Side one of the first bulkhead with CSM laid...

Finished up the water drain holes in the other two bulkheads

Side two of the first one..Actually didn't do too bad with getting the edges of the cutout covered. The top edge will be geting cut away so no worries on that one.

Almost FRIDAY!

tpenfield: My tank is a 28 gallon aluminum tank. I will space it with the strips to keep it off the hull, but the weight of the tank and gas will still be borne by the hull. I don't have an alternative as there is no room to build a "false bottom" to allow the tank weight to be supported by the stringers. There is very little room around the perimeter of the tank (less than 1 inch at the ends, 1/2" on the sides). It was supported only by the rubber strips on all sides, including the top. There isn't much room for foaming it in.

Steve

Friscoboater & others have subbed a recycled tire door mat from wally world, cut into strips under & around the tank. 3M 5200 to adhere them to the tank w/ no room for water to sit between the strips & the tank.

Unless there was major pitting from the original install, using similar materials, in similar locations, in a similar fashion w/ good adhesion between the tank & the strips, should pose no problems....

 

[93bayliner1800]

Re: Floor replacement question

I set my stringers and bulkheads in place and secured them with finish nails and braces in a couple of spots.....then mixed pb and put into a zip lock bag. Had no trouble at all getting it underneath. I squeezed it under allowing excess to come out on each side....then used excess for my fillet.

 

[Woodonglass]

Re: Floor replacement question

The Plastic Bag/corner cut off method ^^^^ works really well from what I understand. Keep it in an ice chest and you'll get longer application time.

 

[jm625]

Re: Floor replacement question

Steve,
Just read through your thread and must say, great job so far! Tuned in and excited to see you're progress, I have an 82 Larson awaiting full resto and reading threads like these do motivate me to get going on it.

Jared

 

[62cruiserinc]

Re: Floor replacement question

Hi guys, I'm back!

I took 3 days off from work and combined with the weekend it gave me 5 days to do non-boat-related stuff around the house. I had been neglecting some needed maintenance around the house and also I have a renovation project that was put on hold while I worked on the boat. The climate here only allows about 4 months of reasonably warm weather to do all the outdoor work and also enjoy some summer with the family. It sure would be nice to be able to work outside at least 1/2 - 3/4 of the year. Combine the bad job market here, high taxes and short summers, places like North Carolina are starting to look a lot better!


I told my wife I have to complete the tabbing of the stringers/bulkheads and installing the deck because the resin I ordered will soon be 3 months old and I know it has a limited lifetime. However, before I can install the deck, I need to finish the gas tank resto and buy new gas filler/vent hoses. So now I am planning on accelerating the work to try and get the stringers and deck installed before cooler weather sets in.

I like the idea of using PVC pipe in the bilge cutouts and plan on using it along with the 5200.

Steve

 

[62cruiserinc]

Re: Floor replacement question

A quick question:

I need to attach two pieces of 2-3" wide by 48" long plywood to ech stringer in the area where the fuel tank access panel will be. These will be glued to the stringer along the top edge so the deck and the access panel can both attach to the stringer.


I have 3/4" plywood pieces left over from previous projects, but have no way of knowing if they are glued up with exterior glue. I don't want to buy a whole sheet of 3/4" exterior plywood for just those two small pieces. HD and Lowes in my area don't sell smaller pieces of 3/4" exterior plywood (and if they did they would want almost as much as a whole sheet!). Can I use some 1x3 boards instead? What type of wood? I have pine and red oak, which aren't particularly good for this application. I did buy some 2x4s made from Douglas Fir recently and have some left over. I could cut 1x3s from them.

Any suggestions?

Steve

 

[Woodonglass]

Re: Floor replacement question

The Doug Fir would work fine. Coat it with Resin and a layer of shredded scrap pieces of CSM and it'll be good to go.

 

[62cruiserinc]

Re: Floor replacement question

Thanks, WOG.

For those who have used the 3M 5200 adhesive/sealer, did you use the regular or fast-cure?

The regular 5200 says it is tack-free in 48hrs, full cure in 7 days. This seems really long. Unfortunately the fast-cure is very expensive ($25 for a caulk tube at the local marine store).

Steve

 

[Woodonglass]

Re: Floor replacement question

Where are you using the 5200? No need for fast cure IMHO

 

[62cruiserinc]

Re: Floor replacement question

I'm using the 5200 to hold the piece of PVC pipe that lines the bilge cutout in the two bulkheads (as was posted on the previous page in this thread as a way to waterproof the cutout edge).

I don't want to have to wait days for the 5200 to cure, but I don't want the PVC to fall off while I'm installing the bulkhead either.

Can I mix up some PB and use it to hold the PVC onto the bulkhead edge?

Thanks
Steve

 

[Woodonglass]

Re: Floor replacement question

Yep, I'd use PB

 

[62cruiserinc]

Re: Floor replacement question

I'm going to use PB to set the PVC in the bulkheads.

I've also decided to use PB instead of PL to bed the stringers. Today I'm placing an order with US Composites for two 5 quart Cabosil containers to make sure I have enough. The 72 hour wait for PL to cure was just too long. Plus I can fillet at the same time If things work out properly. To make sure I have enough time, I will mix the MEKP for a slow-cure (maybe 1%-1.25%). Also I will use the ziploc bag applicator trick that has been suggested here. Another option is the throwaway cake frosting applicators. My son has used these. The tip is plastic or steel, but the bag part is plastic and disposable.


Looks like I will still have to buy a tube of 3M 5200 to attach the plastic strips to the bottom of the gas tank where it lays on the hull. Our local Lowes and HD don't carry it in the store, but I can order it from them much cheaper than the West Marine here.


Steve