water tank repair - polyethelene welding/bonding

[brian w]

hi,

thanks to searching the excellent archives, I've found one of, and (fingers crossed) main problems with the water system on our 33.

for the past two seasons we've had little to no water pressure in either sink. also, we notice water on the cabin floor, particularly after filling the tanks, but also sometimes just overnight. (that's led to the sole delaminating in places, repair for another day). after searching the archives, and in particular Zeida's pictures, I found that on the starboad tank, one of the joints where the hoses enter the tank, had indeed cracked.

so last night I lifted the plywood - I couldn't get it all the way "off" only lifted enough to get the tank out - I assume it will be challenging to get the wood back in (am thinking of lubbing the wood walls with teak oil) and brought the tank home.

I was all prepared to order the 3m 8005 scotchweld, hoping it can all be overnighted. but it occured to me, since I have the tank out and can take it anywhere, are there places I could bring it to be fixed? seems like a pro would have these tools, and may actually be cheaper/easier than buying the full 8005 adhesive and gun.

I saw mention of RV stores, but don't know one in the area (will look further). would an autobody shop be able to do polyethelene repairs? plumbing store?
figured I'd ask the pros.

really hoping fixing the tank will get the water pressure back.

thanks in advance,

Brian
CD33

[s.v. LaVida]

Brian,

The kit is fairly cheap and you can get excellent results with the 3m package I told you about.

It works like magic.

sea u
rit

[Troy Scott]

Brian,

Be sure to ask for the mixing nozzles. You can't use the 3M product without them. Also, there is not much working time. Be ready and work fast.

[JimL]

All automotive body shops have a contact with bumper repair services. These folks can take a destroyed plastic bumper (often made of PE) and put it back to "like new". Turnaround 24-48 hours.

You might check with them.

By the way, I fixed mine with 5200 and no problems since.

Regards, JimL

[brian w]

thanks all,

called 3m to order 8005. they gave me the number for local stores, most of which were the same company with different locations. calling them revealed they only would sell to a company account. so I was stopped by our auto body shop with the tank in the car. he said he'd order the 8005 for me and lend me their gun (the most expensive part). subsequently, his supplier indicated he couldn't get 8005 (or that it wouldn't fit the gun they had) but would check the 3m catalog for a comparable product for polyethylene.

thanks again.

best regards,

Brian
CD33

[Troy Scott]

I bought 8005 over the internet with no problem at all. 3M 8005 is the only product that will bond polyethylene without special pre-treatment of the polyethylene. With the other products it's necessary to use a torch to "convert" the surface to something that will bond. I don't recommend that approach. As for the gun, I made one out of dowels and epoxy. When you get the kit you'll immediately see what will work. You'll also need a mixing nozzle. These are readily available at hobby shops because other bonding products come in similar packages. There is more than one size of these nozzles. I suggest taking the 8005 to the hobby shop with you to make sure you get the right one. Just google 3M 8005 and order it.

[Al Levesque]

If your system is like ours tank leaks should not affect the pressure. The intake side of our pump only needs the line to be able to draw water from the tank. One way to compare lines from each tank is to close off the valves from each other tank and draw from each in turn. If one has been open and allows the pump to draw air you could be losing pressure that way. If each tank draws the same then the pump may be the problem.

[brian w]

thanks. was hoping it would address the pressure problem. it would seem a leak would keep things from being pressurized enough to keep the pump off, but perhaps there are problems elsewhere.

it's been really difficult getting 8005, by the way. of the places 3m gave me, 1 said they'd only sell to a corporate account, 1 said you had to order the nozzles in a box of like 72, and the guns in a box of like 40. googling places found those that carried it, but they said because it was flammable, it had to go ground and would take a week. very frustrating.

-Brian