Hi All,

After a little advice if possible.

We have a homemade lowered sump on our Zetec Locost, fabricated by us... Ally welded by a friend.

The car has a leak when hot, which could be coming from the sump, or could be a gearbox end crankshaft oil seal thats gone... bit hard to say.

I want to smother the welds with some sort of sealant to cross that off the list of possibilities.. Can anyone recomment a product to use?

Thanks

Dan

When I shortened the steel sump on my x-flow I cleaned it up, sat it on some blotting paper, then filled it up with some water to a few inches above the weld line. At first it showed some patches where the welds had leaked, but after a bit of re-welding it was all good.

Maybe you could try something like that?

Clean and Repaint it with a few coats..

quote:

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Originally posted by David Jenkins
When I shortened the steel sump on my x-flow I cleaned it up, sat it on some blotting paper, then filled it up with some water to a few inches above the weld line. At first it showed some patches where the welds had leaked, but after a bit of re-welding it was all good.

Maybe you could try something like that?

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I had all this misory with a sump I welded on my xflow, and no matter what I did, from welding it up further, to adding JB weld over all the welds, painting the outside in enamel paint, etc, I then sold it on ebay as "xflow modified sump, that leaks" for £50
and had a new sump made by a local welder for £120, and the new one has never leaked !!

steve

POR 15 tank sealer will do the job
You'll need the kit with cleaner and etchprkmer but the actual tank dealer is amazing stuff

I welded mine up, sat on the bench full of oil for a couple days and no leaks.

Put it on the engine and yes, you can guess as soon as it was hot it leaked!!!

The problem is that you will be able to clean off the oil from the areas that don't leak,
but oil seeping though the leak will stop anything sticking to it.

The chances are that a leak in an ally weld will be no more than a pinhole (gas pore)
so once found the pore can be sealed with a tap from a dot punch.
It can then be painted if you wish.



HTH
Paul G

Thanks for the ideas all, certainly some food for thought!

putting sealant over the welds will contaminate them so will make it harder to weld - obvioulsy the same applies on the inside due to the oil.

if you don't want to remove from engine, then clean sump and dry it, then use talc to cover the sump, this will make it easy to spot the origin of the oil but depending on location, may not narrow it down 100%

Sounds weird, but I promise it works

Rub a bar of soap over the leaky part, try and shove soap into the seam. Clean off with a wet cloth and cover with araldite.

This was our temporary fix to get home once, it lasted a couple of years

[Edited on 17/11/16 by UncleFista]

As it's an Ali sump start off by plannishing the welds, it will compress the metal into the holes and hopefully stop your problem.

It's always good to break out the hammer anyway on frustrating problems.

To prove its good fill with diesel and leave overnight.

Thanks everyone, gonna whip the sump off at the weekend and try all the various ideas... One of them must work!

I had this on a shortened ali sump on a bike engine. Turns out it was leaking through a hairline crack around one of the lugs where one of the sump bolts went through caused by a homemade baffle plate by the previous owner that wasn't uniform thickness.

When tightening the sump up it obviously torqued the ali and started a hairline crack. I snapped it off to see the cross section of the metal and it was dark all the way through indicating a leak.

Maybe take a look around the areas where the sump bolts pass through to check for any cracks? Not saying it will be that, but just a thought from experience.

Sean

When I shortened my first steel sump I tested it with paraffin and it leaked like a seive. After several attempts at re-weleding and grinding it sill leaked so I gave up, painted it and fitted it. Not sure of it was the paint or that oil is thicker than paraffin but it didn't leak at all.

My advice would be give a good paint!

We took the sump of a week or so ago, and found the seal completely shot at the gearbox end so we are hoping it is that.

We filled the sump with boiling hot water (to open up any cracks / pin holes) and there wasnt a leak in site, filled much higher than the normal oil level.

Will order a new seal and hope its leak free!

Now just 3 CV joints to replace and some new harness belts to fit and it will be ready for summer! :-)