Aluminium Repair

[bob6600]

Have just found a small crack in the sump pan, probably due to hitting one too many speed bumps with this low car. MB price for the part is circa £280, a couple on ebay range from £100-£130. I wouldn't mind the latter but just checked WIS and it's not a simple bolt on - bolt off. The labour charge is probably going to run into a couple of hours at lease which is annoying as it's just down to where it is.

So looking at cheaper alternatives, I though let's find an aluminium welder (person not equipment) and found this by Laser Tools which I rate quite highly. Seems perfect for the job as it is a very small crack in the corner. Anyone got any experience of this item? Video is impressive.

LASER TOOLS 4707 ALUMINIUM REPAIR SYSTEM | eBay

[YOUTUBE HD]SwyglwkZcCU[/YOUTUBE HD]

 

[hotrodder]

I can't see that vid as i ditched flash, if it's the same as this https://www.youtube.com/watch?v=SwyglwkZcCU then it's a zinc based self fluxing solder that exists under many different trade names, others include durafix & lumiweld. Lots of the brands are hyped up to be some wonder invention with all sorts of utter BS about it being welding, brazing or "better" than welding and lots of other utter nonsense. HTS200 is apparently a "second generation" version that they claim is different and better again. Quite how it's different when it's melting temp, specific gravity and various other properties are identical to all the other zinc based solders is anyones guess though

The same thing is also available from many welding suppliers (and probably air con suppliers too) without the BS claims. Usually cheaper too, or at least better value, as SIF 555 Al solder can be picked up for ~ £20 for a pack of 12 rods instead of £15 - £30 for a pack of 5 - 10

The shills in the demos make it look very easy to use and it is on the type of stuff they use in their vids/marketing. Trying to repair a largish casting wit a little DIY style or plumbers gas torch ain't gonna happen though or will at least be very frustrating and boring as neither heat source can supply enough BTUs to get a large chunk of ally upto the required temperature
While they shout about it being stronger than aluminium they always forget to mention that it's more brittle too...

I'm a welder and fabricator and keep some SIF555 to hand for repairing pot metal castings and the odd ally repair that isn't really suitable for TIG welding or brazing with oxy acetylene, flux and 4047*. Something like a radiator is much lighter/thinner than a sump casting and while a pinhole can be fixed with zinc solder and a plumbers blow torch it is beyond boring to do as the torch takes eons to get the rad to the right temperature for the solder to melt and flow. Try and heat the solder out of frustration and it all goes wrong very quickly. While oxy fuel makes more sense from a heating POV it obviously makes the repair a bit trickier at the same time as it's fairly easy to melt the part by accident if you're not paying enough attention
Obviously it's easier to use 'downhand' but fighting gravity with vertical or overhead positional repairs is doable

JB weld is just a reinforced epoxy resin, kinda a DIY version of Devcon or Belzona puttys. Belzona especially is in a different league but then so is the price although that might be partly due to minimum pack sizes i.e. doesn't exist as small tubes?

Welding is waaaaaay better for something like a sump but, as with the zinc based solders, an in situ repair is usually way more difficult i.e. can't get/keep the area clean enough as the heat keeps drawing more oil into the crack. If it's too much aggro to remove the sump to clean it properly and vee out the crack i'd go with an epoxy or fibreglass repair

* 4047 is a eutectic aluminium silicon alloy

 

[bob6600]

Thanks hotrodder very informative. I may go for one of the epoxy based solutions first (one has been recommended on the other side) as it seems an easier solution for me. Thanks again

 

[Stratman]

Is welding a sump in situ safe? I'm thinking of a crankcase full of flammable vapours.

 

[rockits]

I had a rusty sump on an old Cavalier SRi 130 years ago with a leak/whole. Drained the oils, took the sump off. Bit of wire brush work, rub down, some JB Weld with Hammerite treatment and all good. Lasted the 2 years I had the car no problem. JB Weld was good enough for that application.

 

[martyz]

+1 for JB weld, made for that sort of repair.

 

[rockits]

I should think it would be able to be done sump on if oil isn't leaking out. I had to take mine off as it was pretty rusty. Doesn't sound as though you have the same issues or complications though. JB Weld is ideal for this. You have nothing to lose by trying.

 

[streethawk]

I should think it would be able to be done sump on if oil isn't leaking out. I had to take mine off as it was pretty rusty. Doesn't sound as though you have the same issues or complications though. JB Weld is ideal for this. You have nothing to lose by trying.

Aluminium doesn't rust just oxidise. I had to do a lad I knows golf years ago. Took it off and gave it our fabrication department and come back as good as new. We are an aerospace company so we've all the kit.

 

[Bewva]

The problem with trying to do this in situ is that the crack has oil in it. You need it to be spotlessly clean for a proper job which would probably mean excavating the crack to get back to clean metal. Not cleaning the oil out will result in the weld sitting on top rather than filling the crack properly.

 

[bob6600]

Right I think JB Weld will be my first point of call. Will drain the sump and let it sit, carve the crack a little with a Dremmel and then hopefully fix it. I have plenty brake cleaner so will try and ensure it's oil free

 

[Bellow]

HTS200 is apparently a "second generation" version that they claim is different and better again.

A small point. It could be 'second generation' as rods such as these pre-date all welding methods bar arc and oxy/acy torch. My father used to work for the Swiss company Eutectic and the company had a Number 19 rod that did all that. (It also had (paste) solders you could use with a lit match). Eutectic were way ahead in the game.
Second generation or user more skilled than me? Possibly for the former, definitely for the latter!
All the points you (HR) make about applying it are spot on. They are good, but very difficult to get the heat 'just right'. Absolute cleanliness is a must also.

(Not mentioned, is the ability (of Eutectic 19 at least) to join aluminium and steel).

 

[Bellow]

While they shout about it being stronger than aluminium they always forget to mention that it's more brittle too...

Brittle.
A long time ago preparing my sister's first car for its first drive by her (from Aberdeen to Southampton) and servicing the engine, I had my old man on my case urging me to check the gearbox oil. So, I stopped what I was doing and set about checking it. Out with the level plug...and two things occurred simultaneously. One, I realised that this was no 'level' plug - not with that length of steel rod attached. Two, a clunk - as whatever the bolt restrained slid into the bowels of the gearbox. Damn!
Quick, retrieve it! First thing at hand to fish it back to where it had to be was a Eutectic 19 rod. And yes, a bit broke off! Finally, after an age of dicking around I got whatever it was back in place and secured. What about the bit of 19 rod still in there? Well, we drained the oil - no sign of it. So we flushed with paraffin - still no sign of it. So we refilled with paraffin, started the engine and with the wheels free of the ground ran it up and down all the gears umpteen times - still no sign of it. At which point we concluded 'it must have been crushed by the gears' and put the box back to how it should be - drained of paraffin and filled with oil. The car drove to Southampton and the episode was forgotten.
Then, years later, my sister couldn't engage reverse. Yep, you've guessed correctly. When the (local) garage stripped the box they found the reverse selector jammed by ' an inch long piece of aluminium bar'!

This should really be posted in the Hold Your Hand Up To A Stupid Moment thread - but I'd rather hide it here. Yes - these rods are brittle!

 

[bob6600]

Update:

It has been approx 3 weeks now and although I haven't managed to get under the car, the oil level on the dipstick is still on Max! So far so good, hopefully will hold for the year or so I want to keep the car