Courage cracked block

PTmowerMech

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I've got a customer who brought me one with a cracked block. In that same top corner as they all crack. And for the same reason. Loose top cover bolts. I've ever made this repair, so I told him I wouldn't try it. But, I did take a small grinder and cleaned off most of the old repair that someone tried. BTW, one of the reasons I didn't do the repair is because there's still some of the stuff they used the first time, down in the crack, that you can't reach.

With that said, I got some stupid ad on my facebook feed, that showed a guy heating up aluminum and melting some sort of metal onto it. And like all ads, it worked like a charm. So I took to Youtube to check their reviews. I found a few people who knew welding/soldering and they tested it on several different types of metal. On most of the metal, it didn't work. But every video I watched, where they did this to aluminum, it did work. And worked well.

Here's the ad: (turn your volume down)

Here's one of the reviews I watched.
 

StarTech

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I have tried those rods and they don't work as advertise just like JB Weld products don't as advertise. Or at I never had them to work.

What needs to be is for the metal to cleaned up and TIG welded, laying down what they call dimes. Aluminum is very hard to weld due to the oxidization of the surface metal. When laying down dimes you got wait for the aluminum that being welded to cool back down somewhat.

By the time you get the surface oxidization to break for the solder type rods the aluminum melts away itself as it has a much lower melting point than the oxidized aluminum.
 

bertsmobile1

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The stuff has been around for as long as I can remember .
It keeps o being reinvented.
It is a Zinc based SOLDER
Used to be called Alumi-Weld and eazi-weld
It is a quateranary alloy of zinc , bismuth, antimony & aluminium
The earlier stuff had cadimum in there which has been deleted .

It was invented and works really well on aluminium boat hulls
It does not work particularly well on things that get hot like motorcycle engines and lawnmowers because it melts at too low a temperature.

Back in the early days it came with a titanium scriber and you deposited a blob onto the surface then scratched through it to break the tough aluminium oxide layer.
Once you had done that you just kept working the puddle to float off the oxide.

The process is called "Dip welding" down here and is a standard way of welding aluminium with a torch.
The retailers of the rods have been sued regularly down here because the process is not welding, it is soldering or at a pinch braizing because the filler rod is a different composition to the weldment and the parts joined are not molten .

To get it to work you need a lot of operators skills .
The newer stuff is the rods they use to join aluminium radiator cores and in particular joining copper to aluminium cores and that will only work on very clean metal.

IF you use it to fill a Kohler crack for instance over time it will melt out and form beads ( called pearls ) at the bottom of the crack.
And the aluminium has to be clean for it to work, and that is clean with a capital K so there is another reason why it should be avoided as an engine cranjaces would need to be degreaed then vapour blasted before the stuff will take.
And with the earlier rods, iron was poison so if you wire brushed the join area with a steel brush, the tiny amounts of steel would prevent it taking, Stainless was OK but plain steel a no no .

I have had limited success using it to fill small holes in aluminium push mower base plates where a rock has gone through but not a bolt hole or anything that is under stress like a flogged out bolt hole.
Like most things, if the stuff was really that good you would not need to be flogging the hell out of it on late night TV and the web .
And I would definately be wary of recommendations form a Y-Tube hero who seems incapable of properly securing his vice to his bench.

OTOH the stuff is cheap and you can fill a hole in a beer can with it , although why you would want to do that is beyond me .

It does work fairly well of zinc bases castings which I think is what he is incorrectly calling "pot metal" which by defination is anything that is melted in a steel crucible so that ranges from lead sinkers all the way through to carburettor bodies.
It will not work an anything that has been electroplated or anodized .
All of these "escape" clauses are in the instructions .
 

cpurvis

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The bad news is, even using the proper process, not all aluminum alloys are weldable. Two that come to mind are 7075 and 2024.

The good news is, the aluminum alloys used in lawnmower engines are. Tig and Mig welding both work for welding aluminum.
 

bertsmobile1

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You lot use different alloy number than we do but in general Al-Mn alloys do not weld but they are extrusions so you don't want to weld them in any case.
And no not crap, the right tool for fixing leaky bots or installing air con radiators and mower base plates . Wrong thing for mower engines.
FWIW I use Dillon low pressure oxy kit that I bought from Mr Dillion ( the man who invented it ), back in the 70's
HE tried to get them retailed down here but we had a monolopy gas supply in those days as CIG ( Now BOC ) was both the gas supplier, bottle renter & retail outlet .
So he took his idea to the USA where a mob called Cobra started making it and now mob called Henrob market it as the DHC 2000
Being well & truely out of patient Kent the Tin man tinman technologies markets a gun using the same technology but in a conventional pattern called the Mecco Midget , rather than the pistol grip Henrob
people who have never gas welded find the Henrob fanasitic while old hands find it cumbersome because of the pistol grip & weight.

Ed came to my employer, went into the scrap yard, grabbed some aluminium & steel beer cans, cut them dead strait then welded them back together to make airtight double length cans.
His wife then walked deeper into the yard and grabbed some filthy greasy stainless plate and made a series of weld before cutting a comb from an RSJ .
Then to prove a point they grabbed some broken casings and welded them using pieces of broken aluminium from the pile of shreds , no cleaning . just a touch of flux brushed onto the job.
I was hooked
Gas is of course slow but I have welded so many really thin things with it over the decades and most on my friends now own one after seeing how well I could weld anything.
I loaned mine to a customer ( previous business ) who was into Suberu and was forever making stainless turbo traps and paying $100 to get them welded.
Took to it like a duck to water and ended up making 3 complete rolling kitchens in stainless ( he was a food photographer ) before buying one for himself.

I had trouble with aluminium till I forked out for one of Kents ( tinman tech ) TM 2000 orange lenses and since then there has been nothing I can not join together, no hole I can not fill.
In particular Honda walk behind base plates with rock holes , do at least one a month
 
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