need advise - welding metal sheet with stick:/ has ended up like this:D

[the]

hi everyone

i need some advise - I wanted to try to enlarge my sump, used some 4x4 steel welded together ) - holdin liquids no problem - welded it ok - though - i tried to weld it to the sump ) - pressed sheet metal)

http://img812.imageshack.us/img812/3329/47322206.jpg - the pic


- at first i made edges of that walls thicker by using 1.6mm electrode (cuz i tried it recently and it burnt through without that) - after i added more and more layer (though it was having these valeys etc - after i tried to smooth it out with 3.2mm rods (but it just didnt turn up as I wanted.. now the water runs through some little holes all around those welds (not too much but its not tight....
any ideas if i can save it yet? or better to bring to some welder - and TIG it? (or its no way now and it must be grind off? will appriciate any info
thank you

 

[Lewis Medlock]

I was in the REME years ago. I heard a story about a Bedford truck (how true it was I don't know).

There was a thing called BDR which stood for Battle Damage Repair which was basically bodging a vehicle on the battlefield until it could be properly repaired when time and facilities permitted. Part of the BDR research was working out what damage was likely to be sustained and what effect that would have on the performance of the vehicle. One experiment looked into what would happen if a typical Army vehicle (the Bedford 4 tonner) took a round to the sump and all the oil drained out of it, in particular they wanted to know how far the vehicle could be driven with no engine oil before it seized. The story goes that the boffins in white coats obtained a Bedford and shoehorned it into the lab. They drained the oil, set the engine to run flat out and started their stopwatches (or as Murray Walker would say "stopped their startwatches" bless him).

Several hours later the boffins were bored and half deaf, they finished for the day. Next morning they stopped timing the experiment.

Four days later the Bedford was still going strong and they turned it off because if any soldier was driving it they probably would've reached a workshop and the boffins needed the lab for another experiment.


The reason the truck ran for so long was that the mineral oil the Army use had leeched into the cylinder walls over the years, as the engine got hotter the oil seeped back out lubricating the pistons.



My point is that if your initial fabrication didn't leak oil and it was only when you welded this to the sump that you had problems, the porosity may be caused by oil seeping out as it became hot.

Or you just need to practice a bit.


All the best, Jim

 

[Lewis Medlock]

And here's the pic you posted in case imageshack goes down

 

[the]

heh, i appriciate your story bud, though I am not sure how does it solve my welds? just need to know what would be the best solution for me - it grind some material of again, re weld and again again until its without any porosity..,? or TIG it,?

btw thank you for uploading the pic

 

[Lewis Medlock]

Do it again with a stick welder, TIG would be far more susceptible to porosity and MMA far more tolerant of impurities.


Jim

 

[Drains]

What Lewis says (and I wish I'd seen you'd uploaded the pic before I clicked on the image shack link and lost the will to live), but you need to grind the weld back first. And learn how to lay a good bead too.
See how when you were a little kid and did colouring in with crayons and it looked rubbish, and now that you're older, if you had to, you could colour in neatly? Welding's like that. You have to practice a bit, or it'll look like a five year old did it.

 

[Lawnmowerboy]

you would be best off with an external oil tank surely, at the level of the sump and a decent size hose or do you need the depth for a different oil pickup tube?

 

[pedrobedro]

I was in the REME years ago. I heard a story about a Bedford truck (how true it was I don't know).The reason the truck ran for so long was that the mineral oil the Army use had leeched into the cylinder walls over the years, as the engine got hotter the oil seeped back out lubricating the pistons.

I know a scrapyard where they used to sell ex services vehicles and when the vehicles were put into store the engine oil was replaced with vegetable oil. Some new age travellers bought one of those Bedfords with the idea of changing it into a mobile home. They were told about the storage oil and that it needed changing but they thought they knew better. It managed about 3/4 of a mile before it seized solid. I think oil leeching into cylinder liners is a bit of a stretch Hot oil is something like the consistency of paraffin so it will find any pinholes you have left. There should not be much pressure in a sump so you might get away with sealing the inside with something like Petseal.

 

[rich r]

I think what people are saying is that metal was probably already slightly porous, and the oil that has soaked into the pores is now causing those holes to open up when it's subjected to the heat of the welding process. Because the weld isn't good, the holes are a problem.

Grind back that ugly weld, and retry it - if you can lay a nice neat weld, the welding process will have cleared these holes. But welding with 1.6mm rods is tricky and takes a lot of practice.

Practice on similar metal if you can until you can do consistently good welds, then have another go at the sump.

 

[Wallace]

Is the sump still bolted to the block or loose? You might find the gasket face is a bit distorted now and may not pull flat.

Mike

 

[chevy2]

Adding whats already said,
any major welding to sumps require it being ideally bolted to the engine block or something of similar rigidity,
recently did some mods to an ali skyline sump so clamped it to a lump of marble,
handy as the owner of the sump cuts marble in his day job!

I also doubt the story of the army engine lasting two days?
if that engine was run in the real world and under load with no oil the main and rod bearings would be shot way before the bores seized.

Regarding your sump, assuming the crankcase breathes efficiently there should be very little internal pressure,
yes, rewelding would be better but if not thoroughly clean the inside of the sump with brake cleaner then smear all the joints with JB weld.

 

[the]

Is the sump still bolted to the block or loose? You might find the gasket face is a bit distorted now and may not pull flat.

Mike

nope, I have it bolted to the block - using it as a torque plate i know about possibility of distortion so i used a spare block

btw thank you for replies - so I grind that ****ty weld off again - and reweld it - btw - what taqnicue is the best for welding 90° stuff together like here - the wal to the bottom - in 90° any info on that? what movement - circular or just pullin it backwards?

and also - what thicknes of the rod would be the best,,,,? definitely bigger than 1.6 now though , right?

 

[the]

Adding whats already said,
any major welding to sumps require it being ideally bolted to the engine block or something of similar rigidity,
recently did some mods to an ali skyline sump so clamped it to a lump of marble,
handy as the owner of the sump cuts marble in his day job!

..

wow is it TIG I presume? looks awesome ... skylines have them aluminium - its the 26dett version with awd

 

[Terrapin]

Sometimes a far better alternative is to make what is referred to as a sump extension - essentially a spacer plate between the engine & sump with a gasket either side. Give a greater capacity without the danger of grounding extensions sticking out of/off the sump.

 

[rich r]

what taqnicue is the best for welding 90° stuff together like here - the wal to the bottom - in 90° any info on that? what movement - circular or just pullin it backwards?

and also - what thicknes of the rod would be the best,,,,? definitely bigger than 1.6 now though , right?

Have a read of the tutorials at the top of the page, and there's a superb video on YouTube from The Welding Institute - it's a bit 1980s, but everything in it is valid. If you're having to ask how to do a simple T-joint like this, put the sump to one side and practice with some scrap steel - start with nothing thinner than 4mm. Once you've got the hang of it, then return to the sump, otherwise you'll get frustrated and make a mess of it. Stick welding thin metal is tricky, so you need to be fairly consistent and confident before you try it.

 

[chevy2]

wow is it TIG I presume? looks awesome ... skylines have them aluminium - its the 26dett version with awd

Yeah its tig,
modified now to a dry sump system.

 

[chevy2]

Sometimes a far better alternative is to make what is referred to as a sump extension - essentially a spacer plate between the engine & sump with a gasket either side. Give a greater capacity without the danger of grounding extensions sticking out of/off the sump.

Thats one way, another is to weld boxes to the sides to gain capacity without losing ground clearance, putting hinged trap doors in there also keeps the oil in the centre during heavy cornering.

 

[penfold]

That's an ugly weld; it all needs grinding off and starting again. Even then it won't be easy as sump pans are made of fairly thin sheet. Did you clean all the rust off the pan before starting? A MIG is the best tool for this, or OA if you have it; stick is the least suitable welding method available.

As someone else has said you could just bodge it with petseal or something similar.

 

[the]

yeah those weld are horrid I did grind it off as much as the size of the disc allowed me - do you think its weldable now - though still with that porosity,? or as long as there is the porosity it cat be welded good together.-..?

please let me know

 

[Wallace]

There's a lot of slag in there still, I would grind all that out and start again with clean metal and a better fit up.

Mike