Cracked fiberglass fuel tank

[LobsterMobster]

I have a 50 gallon fiberglass fuel tank under the deck in my boat that has a crack, i currently do not use it, because I have another 50 gallon on the other side. I was wondering if there was an easy fix or if its even possible to fix it after fuel has been in the tank. The crack is fairly low on the tank and the tank has a fill, feed, return, transfer, and vent. I didn't do it but i can only assume it happened due to rockhopping. I am not ready to rip up my deck, but it may eventually come to that...

 

[LobsterMobster]

boat is diesel, so don't tell me i need to get a plastic or aluminum tank!

 

[MDI45]

L.M. If you can get to the tank ..you can try draining it and washing (SOAKING)the area with acetone and try to re fiber glass the crack

 

[BillD]

I have a 50 gallon fiberglass fuel tank under the deck in my boat that has a crack, i currently do not use it, because I have another 50 gallon on the other side. I was wondering if there was an easy fix or if its even possible to fix it after fuel has been in the tank. The crack is fairly low on the tank and the tank has a fill, feed, return, transfer, and vent. I didn't do it but i can only assume it happened due to rockhopping. I am not ready to rip up my deck, but it may eventually come to that...

A new term/word here....."rockhopping" ??

What is it ????

 

[F/V First Team]

Engaging rocks that are higher than the depth of ones keel?

If you can access the crack, rub ivory soap into the crack, nice and hard. Prep the area, a little grinding should suffice, glass the area.

Easy peasy


That's Ivory soap
Ivory
Remember: Ivory

This stuff

I can't stress how important it is to use Ivory

 

[winterking]

OK, stupid question, why Ivory?

 

[F/V First Team]

Because it works

 

[LobsterMobster]

Previous owner decided to encounter as many rocks as possible, doesn't soap contain silicate??

 

[F/V First Team]

Sodium Silicate in this instance
The soap creates a barrier so that the fuel doesn't impact the resin trying to bond to the fiberglass already in place.

 

[LobsterMobster]

Thanks, I do not think i will be tackling this issue anytime soon, but always good to know the best route for when I do!

 

[Sailorgp]

I wouldn't use polyester resin for the tank repair...it has poor secondary bonding characteristics. Epoxy would be a better choice...although I'm not sure how compatible cured epoxy and diesel fuel are. Vinylester resin would be another possibility. You might want to search the web for possible solutions Could you repair the tank from the outside?

 

[F/V First Team]

Amusing, since probably all of the boats here are built on those "poor secondary bonding characteristics"

 

[LobsterMobster]

No glassin' from outside, the tank is glassed right to the hull and no space to get at it under the deck, so its sounding like the only option is to cut it up and do a legitimate repair. Thanks.

 

[Sailorgp]

FV/First Team,
You might find this an interesting read...

http://www.amtcomposites.co.za/sites/default/files/media/howto/Advantages%20of%20Epoxy%20over%20Polyester.pdf