Thread Tools Search this Thread Display Modes
Old 10-03-2016, 04:47 PM   #1
4 Rivet Member
ericpeltier's Avatar
Vintage Kin Owner
Superior , Colorado
Join Date: May 2014
Posts: 442
add a port to a fiberglass tank

Hello, all!
I need to add an inlet to a fiberglass waste tank that fits in my 1972 Streamline. Does anyone have experience with this? The big issue....I do not have access to the inside of the tank (shape is too convoluted). All work needs to be done on the outside of the tank. Impossible? Thanks!

1972 33' Streamline Emperor Crown Imperial
1949 30' Spartan Royal Mansion
2012 Nissan Armada
Most of China
ericpeltier is offline   Reply With Quote
Old 10-03-2016, 08:01 PM   #2
Rivet Master
dbj216's Avatar

1986 34' Limited
1975 27' Overlander
Conifer , Colorado
Join Date: Jun 2009
Posts: 4,590
Images: 1
I'm surprised it is a fiberglass tank. But I don't know your vintage trailer at all. If it is fiberglass, I believe you could drill a hole, and "lay up" fiberglass and resin around the fitting you want to add. Kinda like working on a boat.

Airstream waste water tanks are polyethylene plastic, usually rotomolded. This material is thermoplastic, meaning it can be melted and retain its original strength. Factories can "spin weld" fittings to polyethylene tanks. Some folks have heat guns where you can "braze" a fitting to a tank with pretty good success.

And I use rubber grommets because I'm generally lazy and can't spin weld. With this component you get the right size hole saw, deburr the hole you drilled, install the grommet, and then install the fitting you want. These grommets will not work on fiberglass tanks as they are too rough on the outside. The grommet seals on the ID of the drilled hole, and the OD of the installed ABS pipe. Most of my connections were 1 1/2 ABS pipe.

Attached Thumbnails
Click image for larger version

Name:	1312 Plumbing New Holding Tanks Grommet Side View.jpg
Views:	28
Size:	88.5 KB
ID:	272813   Click image for larger version

Name:	1404 Waste Tanks Grommets Installed.jpg
Views:	32
Size:	293.5 KB
ID:	272814  


dbj216 is offline   Reply With Quote
Old 10-03-2016, 08:36 PM   #3
Rivet Master
68 TWind's Avatar
1968 24' Tradewind
Oxford, , Mississippi
Join Date: May 2009
Posts: 1,522
When I repaired my 68 Trade Wind, I had to replace the black tank. I ordered a factory replica from Inland RV. Very high quality fiberglass, and expensive. It came with no fittings, I had to cut the hole for the vent stack and the toilet. Fittings were included with the tank and following the instructions I fiberglassed the fitting in. I a used West System epoxy resin instead of polyester and fiberglass cloth. The process was very easy to do. Make sure you rough up the gel coat before you glass in the fittings to give the resin better adhesion.
Bruce & Rachel
68 Trade Wind
2001 Toyota Tundra
68 TWind is offline   Reply With Quote
Old 10-03-2016, 08:47 PM   #4
Rivet Master
65CV's Avatar
1959 26' Overlander
Western , Massachusetts
Join Date: Sep 2005
Posts: 1,457
Images: 6
Try the Fastener section here:
65CV is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Black Tank, Grey Tank, New Tank, Old Tank Bunkroom Waste Systems, Tanks & Totes 3 07-22-2014 09:35 PM
any residents of Sequim ,Port Townsend or Port Angeles kingfisher24 On The Road... 6 10-15-2013 09:57 AM
External port from water tank Jeremy9107 Plumbing - Systems & Fixtures 1 09-27-2012 05:14 PM
Does old fiberglass insulation equal new fiberglass insulation? Petethefeet General Interior Topics 7 11-14-2010 01:16 PM
Fiberglass black tank Wooden Rivet Waste Systems, Tanks & Totes 1 07-31-2010 09:39 PM


This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:10 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.