Log in
Search
Latest topics
» **VOTE-ON-THE-NEXT-COX-ENGINE-OF-THE-MONTH** (December 2024)by 1975 control line guy Today at 5:58 pm
» music vids.. some of your favorites
by HalfaDave Today at 5:18 pm
» EXTREMELY RARE COX THIMBLE DROME PROTOTYPE "BLACK WIDOW" GAS MODEL AIRPLANE
by a betancourt Today at 2:44 pm
» Really Nice Free Flight Video
by akjgardner Today at 10:36 am
» More Fun with the Scanner: My May '67 Issue of Model Airplane News: "The Demoiselle"
by Kim Today at 10:27 am
» Free Flight Radio Assist
by rdw777 Today at 10:25 am
» ebay Top Flight Nobler. Oh well......
by Ken Cook Yesterday at 4:08 am
» Cox control line three line throttle
by 049kid Sun Dec 08, 2024 11:35 am
» "Cox Flying School" in M.A.N. May, 1967
by Kim Sun Dec 08, 2024 6:54 am
» Automobiles you don't see everyday...
by Oldenginerod Sat Dec 07, 2024 3:44 pm
» Cox 020 PeeWee rebuild questions
by LooseSpinner99 Sat Dec 07, 2024 3:33 pm
» Tiny Glider
by rdw777 Sat Dec 07, 2024 2:37 pm
Cox Engine of The Month
sealing leaky plastic tank?
Page 1 of 1
sealing leaky plastic tank?
I have a tank plastic tank that has a back plate that leaks around the seams. I tried super glue but the fuel seems to dissolve it. Any suggestions ? Don
dontrinko- Moderate Poster
- Posts : 29
Join date : 2015-05-15
Re: sealing leaky plastic tank?
RTV?
Aluminum safe sealant?
Visit your local auto parts store.
Make sure your choice is aluminum safe since you will probably use it for plastic to aluminum or aluminum to aluminum and so little is needed a tube lasts a very long time. Regular RTV silicone is acidic and will erode aluminum, eventually destroying thin parts.
Phil
Aluminum safe sealant?
Visit your local auto parts store.
Make sure your choice is aluminum safe since you will probably use it for plastic to aluminum or aluminum to aluminum and so little is needed a tube lasts a very long time. Regular RTV silicone is acidic and will erode aluminum, eventually destroying thin parts.
Phil
pkrankow- Top Poster
- Posts : 3025
Join date : 2012-10-02
Location : Ohio
Re: sealing leaky plastic tank?
ON a Cox Reed tank to Back plate- there is a small raised section on the tank back and on the perimeter mating surface of the tank a very shallow groove...some folks saliva wet a cotton thread to add in the groove, I personally use Permatex Anaerobic gasket maker as it seems fuel proof and doesn't react to the aluminum or plastic and will not set hard and glue the pieces together
http://www.permatex.com/products-2/product-categories/gasketing/anaerobic-gasket-makers-flange-sealants/permatex-anaerobic-gasket-maker-detail
I also us a 2/56 bottoming tap to chase two extra threads into the case after surface facing the back of the case on a flat glass or other flat surface using 600 grit wet dry paper and oil to remove the original raised burrs from the drilling of the 4 holes
Reason...Cox had an exact screw length..Estes and other sources are not true length and some too long... There is plenty of depth remaining in the holes and by adding a deeper hole I don't worry about false tightening and always get a good tank to back plate seal.
The Du Bro Cat No 360 2/56 tap and drill is NOT a bottoming tap...I just grind off the lead in tip and have a bottoming tap that works just fine...much cheaper than the shipping cost of the real bottoming tap from McMaster or Grainger etc
The 4 tank to case screws get a twist of cotton from a Q-Tip, about a 0.5 inch long, turned clockwise near the head of the screw...not very much just enough to foul the threads in the tank back plate hole
http://www.permatex.com/products-2/product-categories/gasketing/anaerobic-gasket-makers-flange-sealants/permatex-anaerobic-gasket-maker-detail
I also us a 2/56 bottoming tap to chase two extra threads into the case after surface facing the back of the case on a flat glass or other flat surface using 600 grit wet dry paper and oil to remove the original raised burrs from the drilling of the 4 holes
Reason...Cox had an exact screw length..Estes and other sources are not true length and some too long... There is plenty of depth remaining in the holes and by adding a deeper hole I don't worry about false tightening and always get a good tank to back plate seal.
The Du Bro Cat No 360 2/56 tap and drill is NOT a bottoming tap...I just grind off the lead in tip and have a bottoming tap that works just fine...much cheaper than the shipping cost of the real bottoming tap from McMaster or Grainger etc
The 4 tank to case screws get a twist of cotton from a Q-Tip, about a 0.5 inch long, turned clockwise near the head of the screw...not very much just enough to foul the threads in the tank back plate hole
fredvon4- Top Poster
-
Posts : 4013
Join date : 2011-08-26
Age : 69
Location : Lampasas Texas
Re: sealing leaky plastic tank?
Thanks; This actualy the back plate to a Testors 049. I have some permatex on order that is resistand to oil , gas and several other solvents. Don
dontrinko- Moderate Poster
- Posts : 29
Join date : 2015-05-15
Re: sealing leaky plastic tank?
Not trying to be snarkey ----my comment below is so YOU can get better information
This is the Cox Engine Forum BUT we all have many kinds of model engines so there is a place for Non Cox engines
You asked in the Engine Forum for Cox Engines so I assumed it was a reed valve Cox .049 you needed help with
don't sweat it as most all of us just want to help. When you ask questions please describe whet we are trying to work on so you get relevant answers
This is the Cox Engine Forum BUT we all have many kinds of model engines so there is a place for Non Cox engines
You asked in the Engine Forum for Cox Engines so I assumed it was a reed valve Cox .049 you needed help with
don't sweat it as most all of us just want to help. When you ask questions please describe whet we are trying to work on so you get relevant answers
fredvon4- Top Poster
-
Posts : 4013
Join date : 2011-08-26
Age : 69
Location : Lampasas Texas
Re: sealing leaky plastic tank?
I get good answers here so.... my question was generic, my problem is specific. Thanks, Don
dontrinko- Moderate Poster
- Posts : 29
Join date : 2015-05-15
Re: sealing leaky plastic tank?
dontrinko wrote:I get good answers here so.... my question was generic, my problem is specific. Thanks, Don
BTW, One of the solvents used to soften CA glue is nitro methane.
George
gcb- Platinum Member
- Posts : 908
Join date : 2011-08-11
Location : Port Ewen, NY
Re: sealing leaky plastic tank?
Thanks George, CA was my 1st try and the back leaked like a sieve. The only good part was that it was easy to remove. I next tried some gasket cement I have, Still leaks.
I have some Permatex on order that is supposed to be resistant to Gasoline, oil and other common solvents. Don
I have some Permatex on order that is supposed to be resistant to Gasoline, oil and other common solvents. Don
dontrinko- Moderate Poster
- Posts : 29
Join date : 2015-05-15
Similar topics
» OK Cub plastic tank
» cox plastic fuel tank
» Plastic tank issues
» Plastic tank Repair
» *Cox Engine of The Month* Submit your pictures! -April 2022-
» cox plastic fuel tank
» Plastic tank issues
» Plastic tank Repair
» *Cox Engine of The Month* Submit your pictures! -April 2022-
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum