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

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

Post by ProPower engines »

Stop using a mig welder. Oxy.Acet torch. Same weld quality as a TIG in the right hands.
The process was developed to weld cr. moly for aircraft frames The Acet. acts as the shielding gas when it burns.
Never seen a pan made with a mig that did not have a few pin holes. Stops and starts go cold to hot to cold again bad metal flow out and leaks result.
Practice with a small tip to start till you get the perfect puddle action just like a tig. =D>
Real Race Cars Don't Have Doors
Chris_Hamilton
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Re: Just made a sump. How do I seal the weld leaks?

Post by Chris_Hamilton »

Lots of good info and quality gas welding equipment here:https://www.tinmantech.com/products/welding/
High quality metal, body and paint work
http://www.spiuserforum.com/index.php?t ... inia.9030/
allencr267
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Re: Just made a sump. How do I seal the weld leaks?

Post by allencr267 »

It says temporary, but you know how temp seems to turn into permanent.

https://www.skygeek.com/la-co-11475-oyl ... -5841.html

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

Post by falcongeorge »

Walter R. Malik wrote: Thu Feb 27, 2020 9:12 am
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.
simple, works well, no need to re-invent the wheel. I have done this several times, lasts virtually forever.
peejay
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Re: Just made a sump. How do I seal the weld leaks?

Post by peejay »

I have seen oil pans pass the kerosene test on the bench for hours, but weep oil on the engine. Not sure if vibration caused them to crack, or the crack was already there but didn't leak when stationary.

I have re welded them with success. If you want to do the job only once, use a sealer like the fiberglass resin mentioned earlier.
Roy
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Re: Just made a sump. How do I seal the weld leaks?

Post by Roy »

I'm going to seem like a jerk here, so I do apologize..its not really meant to insult. Learn how to weld. Get some scrap pieces and start playing with it. If your mig uses shielding gas, buy a roll of solid wire. The glow as it cools will look different if there's a crack or pinhole. I have welded quite a few gas tanks, aluminum fuel tanks, air tanks, water pipes, etc etc. A leak free weld is very easily attained as long as the machine is set right and what you're welding is cleaned properly (i normally just touch it with a grinder if steel, if its shiny its clean.) Don't be afraid to burn through! You want to weld as hot as you can without it burning a hole, that will burn off impurities ahead of you and give your puddle a better chance of cooling in one piece. Flux wire works good in a lot of instances but hard wire teaches you how to weld. You don't have an extra puddle of flux hiding your metal.

Whatever you do, do NOT weld something you cleaned off with chlorinated brake cleaner. It can and will kill you
dannobee
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Re: Just made a sump. How do I seal the weld leaks?

Post by dannobee »

I'll give him the benefit of the doubt that he at least knows somewhat how to weld. When using those kits, it's almost always about the prep. You have to clean the mill scale off of the metal before you weld, otherwise they'll never seal up. Sand, grind, sandblast, whatever it takes to get the metal shiny and bare. THEN weld it up.

Regarding the epoxy gas tank stuff, it works great. Had a green flag pit stop once where something on the track punctured the oil pan and got us black flagged for an oil leak. Got the epoxy patch prepped, jacked up the car, told the driver to rev it up (dry sump engine), cleaned the pan with brake cleaner, then slapped the patch up there. It didn't leak or seep at all. The "patch" was a piece of sheet metal with the epoxy around the perimeter.
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Re: Just made a sump. How do I seal the weld leaks?

Post by rebelrouser »

Have not built an oil pan for a long time, lots of reasonable priced ones on Ebay. But when I did build them, I did it old school with Oxy, acetylene, torch. Good clean metal, and I use extra light so I can really see the weld puddle as I am welding. After it is welded, look it over and just flow the weld bead and smooth out any spots you may think will leak. I just filled mine with parts solvent, mineral spirits, Marked any leaks, drained and blowed the pan dry and again just heat and flow the bead. Worst part of building a pan was getting the weld scale out of the pan, seldom had any leaks. I use the torch, because a mig welder welds at a constant rate, making you hurry and make mistakes. A good Oxy, acetylene job looks almost as good as a Tig weld. I build headers with a torch as well. Had one guy ask me why I did not Tig weld my stuff? I just looked at him and said do you see a Tig welder in the shop? Poor boys can't afford a Tig welder. Funny my son-in-law gave me a used Tig welder, and I am so used to using the torch, the only time I use it is for stainless.
PSA
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Re: Just made a sump. How do I seal the weld leaks?

Post by PSA »

I'm not sure if it's built from aluminum or steel, but for steel you can use regular lead for body work.
AC sports
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Re: Just made a sump. How do I seal the weld leaks?

Post by AC sports »

Guys this was finished quite a while ago. The small pinhole leaks were gone over with solder as suggested and as i planned .
So far all good and no leaks. If i had to do it again though I'd either oxy it or tig it.
Roy
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Re: Just made a sump. How do I seal the weld leaks?

Post by Roy »

Leave it to me to go through old posts out of boredom and not pay attention to dates!
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Re: Just made a sump. How do I seal the weld leaks?

Post by n2omike »

JB Weld. Seriously... JB Weld.
I've used it numerous times to seal gas tank leaks... some repairs have 10+ years on them. Back in the early 90's I drilled and ran a 1/2" aluminum fuel line through the sending unit. Hose clamped it to the original line and JB Welded it to seal where the hole was drilled. Worked for 20+ years before I changed it out... and still didn't leak. The stuff might not be pretty, but it can be magic. lol
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Re: Just made a sump. How do I seal the weld leaks?

Post by jsgarage »

I've built gas tanks and oil pans and rewelding leaks (on both sides) works for me. On aluminum I use TIG and on sheet steel an oxyacetylene torch. But never with a MIG. I once fixed a pinholed gas tank on a mid-engined car that needed the whole powertrain removed to access the tank. I used BONDO! Wire-brushed the pinhole till it was shiny, sprayed the thing with Isopropyl alcohol and gave the Bondo 24 hrs before adding gas. A temporary repair that I really need to fix one of these days, but its held for 25 years now... NItrous Mike's JB Weld fix should be maybe better for strength.
engineguyBill
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Re: Just made a sump. How do I seal the weld leaks?

Post by engineguyBill »

I have used JB Weld, very successfully for this type of repair. Make sure that the surfaces are clean and dry prior to repair. The stuff will last indefinitely and will not crack like bondo is likely to do . . . . . . .
Bill

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