Having used my car for the first time I have noticed that the sump has sprung a leak. It is an ali. job that was cut and welded to reduce its depth which I purchased from Ebay. The welding looks good but after just one run it is definitely leaking. So, as I can't weld ali. and don't know anybody who can, I was wondering if I can remove the sump and bond the joint on the inside with something like araldite?
I can weld ally but your a long way away, if you can find some one local to you i would get it welded, bonding is not really an option, sorry.
Oh dear, the welding introduces porosity and is difficult to eliminate.
Is there not a steel jobbie that can replace it?
I'm with welderman really, welding is the proper solution.
I have seen
this though, which is said to seal porus ally, might be worth a try if your really stuck.
When you've done whatever repair, fill the sump to above the repair with diesel, and look for any leaks, diesel will find them.
[Edited on 30/5/08 by r1_pete]
To repair porous ally castings a long time ago we used a product called Devcon. Just painted it ionto the outside of the casting (A series FWD
gearboxes mostly) left it to go off and hey presto.
I'll have a look to try and find some more info.
Cheers,
Mike
Edited to add linky thing for Devcon
[Edited on 30/5/08 by MikeCapon]
paint on stuff sounds the way to go, glue will never work, I doubt even JB Weld will manage
Frost sell some stuff that sounds exactly like the Devcon MikeCapon suggests.
http://www.frost.co.uk/item_Detail.asp?productID=8393&frostProductName=Glyptal+(946ml%2C+US+Quart)&catID=24&subCatID=32&FrostCat=Paint
ing&FrostSubcat=Eastwood
That is if it's porous and hasn't got a pinhole.
Edit: Bah r1_pete already linked to it - great minds and all that 
[Edited on 30/5/08 by iank]
Hi
Has any one tried techno-weld on larger items.
Linky
I have used it succsefully on a few ali brackets.
Wreck one model RC glow engine crankcase, through distortion.
Risky but may work on your sump.
You do need to be skilled with you hands
though. its like difficult brasing.
Best is still to get a pro ali welder.
quote:
Originally posted by rf900rush
Hi
Has any one tried techno-weld on larger items.
Linky
I have used it succsefully on a few ali brackets.
Wreck one model RC glow engine crankcase, through distortion.
Risky but may work on your sump.
You do need to be skilled with you hands
though. its like difficult brasing.
Best is still to get a pro ali welder.
The bike shop uses some black two part gunk to repair cracked alloy crankcases and it never fails. They clean the area up with thinners, mix the stuff and spread it on. It's a lot easier than welding or Techno.
Believe me guys, Devcon is the stuff you need. I worked with this stuff in the 80s when I worked at the Rover factory in customer service. We used
this stuff to fix new cars
but it almost never let us down. As with all these magic goos the prep is the most important part of the job.
can you not get stuff like what you use to stop fuel tanks leaking?
quote:
Originally posted by speedyxjs
can you not get stuff like what you use to stop fuel tanks leaking?
I holed my sump last year and did techno weld it - beware you need to get sump metal to 400 deg C and you will need something bigger than a blow
torch as ali disipates the heat too much.
Did eventually get it fix about 99% only weeped a wee bit.
quote:
Originally posted by Mr Whippy
quote:
Originally posted by speedyxjs
can you not get stuff like what you use to stop fuel tanks leaking?
the two part putty?
does work but the surface has to be spotless when applied.
Whatever you do, DON'T use Petseal. It's an epoxy resin sealent that's designed to seal leaky petrol tanks. The manufacturer said
it'd be fine in a leaky sump (same problem as you, porous welds or a pinhole or two).
It seemed fine, and set to a hard finish in the sump. Brilliant. No drips.
Luckily I ended up removing the sump a couple of months later (needed to change gearbox and thought I may as well take a look as it had started
dripping a bit again) - the petseal had bubbled, cracked and there were big hard flat flakes of the stuff floating around in the oil. How it
didn't completely block the oil pickup and kill the engine is beyond me. Very lucky.
Oh, and it's an absolute sod to get off again. Took about 4 hours to chip the remains off the inside of the sump (why oh why did I weld the
baffles in....).
Mark (fella who welded it in the first place) has kindly offered to buzz over the welds again in an attempt to seal it up, which is exactly what I
should have done the first time.
Get it rewelded! You should be able to identify where it's leaking if you fill it up with thinners and put it on a paper towel. Mark all the wet
spots and get them rewelded.
Devcon is awesome stuff. We use it at work for fixing damaged ali bits and pieces. Just dont get it in your eyes!
Remember using Devcon years ago on new BMC 1300s that had leaking gearboxes . Always worked . If you can find the leak then clean up the area and degrease before applying Devcon to the outside
Yes I used "Belzona Molecular Metal" on the BW35 auto ransmision casing of a Wolseley 18/85 (1800 Landcrab) --- the casing was badly cracked up after hitting a boulder, it went on to do at least another 90,000 miles.
quote:
Originally posted by djtom
Whatever you do, DON'T use Petseal.
which devcon product is the one to use ?