We are currently running on the new domain and server: www.Speed-Talk.com

IMPORTANT: Update your bookmarks to https://www.speed-talk.com/forum/
(Right-click the URL and select "Bookmark this link")

Just made a sump. How do I seal the weld leaks?

General engine tech -- Drag Racing to Circle Track

Moderator: Team

AC sports
Pro
Pro
Posts: 254
Joined: Mon Jun 03, 2013 6:25 am
Location:

Just made a sump. How do I seal the weld leaks?

Post by AC sports » Thu Feb 27, 2020 8:33 am

As it says guys.
I cut up and extended an old sheet metal sump, added trapdoors and a baffle... Happy with the result but im not a welder and I used a mig on the 0.050" sheetmetal.
I was expecting a few leaks.....
So:
1, Any tricks to finding them? I used kerosene but may add some colour to it to make the leaks more visible.
2, how do I seal them up? Re mig or can I use a soft solder over my suspect welds?
3, Will a soft solder hold in the long run? Any issues using it as a sealer over my suspect areas so to speak?

Dutchman
Member
Member
Posts: 120
Joined: Sat May 11, 2013 9:15 am
Location: Bohemia ny

Re: Just made a sump. How do I seal the weld leaks?

Post by Dutchman » Thu Feb 27, 2020 8:54 am

Spray a soapy solution on the outside of the pan and blow compressed air on the inside.
Warm the pan up with a torch and recheck,may expose a bad weld when it's hot also.

Walter R. Malik
Guru
Guru
Posts: 4808
Joined: Tue Jul 24, 2012 11:15 am
Location: Roseville, Michigan (just north of Detroit)
Contact:

Re: Just made a sump. How do I seal the weld leaks?

Post by Walter R. Malik » Thu Feb 27, 2020 9:12 am

AC sports wrote:
Thu Feb 27, 2020 8:33 am
As it says guys.
I cut up and extended an old sheet metal sump, added trapdoors and a baffle... Happy with the result but im not a welder and I used a mig on the 0.050" sheetmetal.
I was expecting a few leaks.....
So:
1, Any tricks to finding them? I used kerosene but may add some colour to it to make the leaks more visible.
2, how do I seal them up? Re mig or can I use a soft solder over my suspect welds?
3, Will a soft solder hold in the long run? Any issues using it as a sealer over my suspect areas so to speak?
IF they are merely pin holes or seepage ... Brush-on some fiberglass resin over the entire weldment on both sides is the easiest solution.
Paint it with "hammer finish" paint and you'll never see it.
http://www.rmcompetition.com
Specialty engine building at its finest.

prairiehotrodder
Guru
Guru
Posts: 1161
Joined: Sat Dec 24, 2011 10:02 am
Location: melfort saskatchewan Canada

Re: Just made a sump. How do I seal the weld leaks?

Post by prairiehotrodder » Thu Feb 27, 2020 9:41 am

I have welded on lots of sumps with a mig. There is always a leak or two no matter how perfect the weld looks. I cut a chunk of an old tire tube with the valve stem on it and hose clamp it over the filler neck of the gas tank. Then pressurize the tank with a few PSI of compressed air and use soapy water to find the leaks. Then mark them, let out the air, fix them with the welder, Re-check.

Brian
The Word of God is quick and powerfull
www.therocketshop.blogspot.com

chevyfreak
Pro
Pro
Posts: 349
Joined: Sat Oct 04, 2014 4:23 am
Location: south africa johannesburg

Re: Just made a sump. How do I seal the weld leaks?

Post by chevyfreak » Thu Feb 27, 2020 9:57 am

AC sports wrote:
Thu Feb 27, 2020 8:33 am
1, Any tricks to finding them? I used kerosene but may add some colour to it to make the leaks more visible.
2, how do I seal them up? Re mig or can I use a soft solder over my suspect welds?
3, Will a soft solder hold in the long run? Any issues using it as a sealer over my suspect areas so to speak?
Been thru the sump building and modifying proses couple of times. Tracing leaks can be tiresome. Take your time double check everything. Worst frustrating moment is finding a leak when its in the car, and as mentioned heat it, or leave it out in the sun with your checking fluid in seperate container, when nice and hot then recheck it. Can use hydraulic oil as well as most is sae10, or brakefluid.
Best way to seal your weld is solder all over your welds on the outside.
The reweld where it leaks doesnt always work or makes it worse. Sadly i had one of those before.
Silicone Sealer or an epoxy doesnt hold, as a temporary fix its ok, but not in long run.

Chevyfreak.
Bowtie for life

User avatar
Caprimaniac
Expert
Expert
Posts: 907
Joined: Fri Nov 18, 2011 1:17 pm
Location: NORWAY

Re: Just made a sump. How do I seal the weld leaks?

Post by Caprimaniac » Thu Feb 27, 2020 10:29 am

I have done a couple. Used mostly water.
Grund down leaky points and rewelded.

However- last I did had so manu leaks and very hard to locate soI gave up and thrashed the whole thing.

Ended up buying new sump- with issues too...
How to turn GURU in an instant.....

AC sports
Pro
Pro
Posts: 254
Joined: Mon Jun 03, 2013 6:25 am
Location:

Re: Just made a sump. How do I seal the weld leaks?

Post by AC sports » Thu Feb 27, 2020 10:41 am

So a soft solder melted into the suspect areas will hold long term?

User avatar
BOOT
Guru
Guru
Posts: 1749
Joined: Fri Apr 09, 2010 6:23 pm
Location: Michigan

Re: Just made a sump. How do I seal the weld leaks?

Post by BOOT » Thu Feb 27, 2020 11:28 am

Long ago when young and broke a friend of mine had a rusty leaky oil pan on a farm truck he bought and it was before computers so maybe that's why the salvage yard gave him the wrong dipstick/seal oil pan. Anyways he decided to use silicone cause we had to have it back together so he could work Monday. We wire wheeled n coated the entire sump with a tube of clear silicone I had, thing must of had 50 or more pin holes but it didn't leak! Later when he blew that engine up, I bought the truck and pulled that engine to replace it. That pan still didn't leak but you could see thru the clear silicone the oil seeping in a few spots but not leaking LOL
Channel about my projects https://www.youtube.com/user/BOOT350V

I know as much as I can learn and try to keep an open mind to anything!

If I didn't overthink stuff I wouldn't be on speedtalk!

Protech Racing
Member
Member
Posts: 63
Joined: Tue Nov 28, 2017 2:51 pm
Location:

Re: Just made a sump. How do I seal the weld leaks?

Post by Protech Racing » Thu Feb 27, 2020 11:50 am

You can also use some flux and braze the leaky spots.

engineguyBill
HotPass
HotPass
Posts: 1185
Joined: Fri Feb 26, 2010 11:15 am
Location: Gold Canyon, AZ

Re: Just made a sump. How do I seal the weld leaks?

Post by engineguyBill » Thu Feb 27, 2020 12:10 pm

^^^^^^^^^^^^^^^^ THIS ^^^^^^^^^^^^^^^^^^

Or, silver solder.
Bill

Perfect Circle Doctor of Motors certification
SAE Member (29+ years)
ASE Master Certified Engine Machinist (+ two otherASE Master Certifications)
AERA Certified Professional Engine Machinist

Schurkey
HotPass
HotPass
Posts: 1498
Joined: Sun Mar 01, 2009 2:42 am
Location: The Seasonally Frozen Wastelands

Re: Just made a sump. How do I seal the weld leaks?

Post by Schurkey » Thu Feb 27, 2020 6:28 pm

We used to have to deal with 3" tubing, bent sections welded together, and beaded on each end to retain a silicone-rubber hose connection for use with City Bus cooling systems. Lots of it was brass tubing, some was stainless, some was coated mild steel.

The company that supplied the tubes couldn't weld worth a shit. It's like they were made by some guy in his home shop, using Harbor Freight equipment.

We re-welded the tubes until they didn't leak. Never considered soldering them. 'Course, these tubes would be pressurized by the "radiator cap", whereas an oil pan has little or no pressure inside; and maybe vacuum.

BigBlocksOnTop2
Pro
Pro
Posts: 487
Joined: Thu Mar 21, 2013 12:03 pm
Location: Chancellorsville Battle Field, Chancellorsville, Virginia

Re: Just made a sump. How do I seal the weld leaks?

Post by BigBlocksOnTop2 » Thu Feb 27, 2020 7:57 pm

That s the thing with wire feed welding a fluid vessel. The starts and stops can cause a slag pocket. With time and vibration the slag pocket cracks out and there's a leak. Been there and done that. Nice looking welds too, not to mention. Just the beast with wire feed welding. TIG is the way to go....

AC sports
Pro
Pro
Posts: 254
Joined: Mon Jun 03, 2013 6:25 am
Location:

Re: Just made a sump. How do I seal the weld leaks?

Post by AC sports » Fri Feb 28, 2020 11:38 am

Update on this. I ground the welds down and re did them. Much better job....but 2 small weeps. May do those areas again then melt some soft solder over the area.

dondon
New Member
New Member
Posts: 43
Joined: Wed Sep 09, 2009 6:30 pm
Location:

Re: Just made a sump. How do I seal the weld leaks?

Post by dondon » Fri Feb 28, 2020 12:16 pm

i had a pin hole in an oil pan, I painted it with por 15 that stopped it. pan was off when I painted it.

stealth
Guru
Guru
Posts: 1129
Joined: Fri Jun 30, 2006 9:37 am
Location:

Re: Just made a sump. How do I seal the weld leaks?

Post by stealth » Fri Feb 28, 2020 9:47 pm

Clean well and coat with jb weld. Smooths over the poor appearance of weld area and seals very well...
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

Post Reply