soldering aluminum?

[Soundguy]

I believe oil will burn before aluminum will melt... At least.. it's been my experience that it would.. IE.. a propane torch.. a little care.. and good cleaning techniques.

soundguy

 

[Bill_C]

I believe oil will burn before aluminum will melt... At least.. it's been my experience that it would.. IE.. a propane torch.. a little care.. and good cleaning techniques.

soundguy

Gotta agree with Soundguy on this...otherwise aluminum pistons or heads wouldn't hold up in infernal combustion engines....

 

[john_bud]

I believe oil will burn before aluminum will melt... At least.. it's been my experience that it would.. IE.. a propane torch.. a little care.. and good cleaning techniques.

soundguy

Maybe, but a propane torch can melt aluminum too. I know that on steel it takes getting the metal dern hot for much longer than imagined to get all the bubblies to stop. I can't imagine that being easier with Al.

Bill_C, You do realise that combustion temperatures are ABOVE the melting point of aluminum, right? The don't melt because there is active oil cooling from a squirt hole in the rod and the hot gasses are exchanged for cold gasses pretty often. Run too hard too long and the cooling is swamped and the temps exceed 1220F and there are issues. Most of us don't run that hard or that long. Remember the 426 Max Wedge that came with a warning from the factory that full throttle runs exceeding 15 seconds could cause internal engine damage? Ever see a hard run V8 at night with the exhaust manifold glowing red?

 

[Egon]

Use the epoxy to fix the crack. Probably end up with a better fix.

 

[varmint]

Egon: I am leaning towards using the epoxy fix. I think that the crack occured after any oil was in the cooler. You can tell it was used, but not for a while, and there's no liquid oil in it a present. The crack is a tiny area just where the machined alum. fitting was brazed to the alum. sheet metal plate that is the top of the cooler. I'm guessing it got levered when there was a hose attached. There's no thickness there in the sheet metal to drill or otherwise plug. (I'd attach a foto, but a friend has the cooler, he'd tried to find a specialist welder to fix it for me). The manufacturer tells me: A) they can't/won't rebraze it, B) heating it to weld will cause more problems, C) my only hope is epoxy.
I still like the idea of alum. solder, but I will "test" some before going any further on the cooler.

 

[Soundguy]

Do what you wan't.. but I can't imagine a glue on fix will be better than a metal patch.. either solder or .. as others have pointed out.. a tig..

Glue fixes tend to fail when you need them... I'd hate to be loosing oil out of an oil cooler because an epoxy scab cracked as the base metal it was attatched to expanded or contracted from heat/cooling at a different rate than the scab did.

soundguy

 

[RWolf]

If you have a friend in the aviation field ask them for some pro-seal. It's probably available to the commerial field but under a different name and I'll see if I can find out. It's similar to epoxy but works much better, lasts longer (i.e. permenent). As long as the parts are clean it applies as a thick paste or can be diluted to a watery solution. When it sets up it's oil, fuel and water resistant.

 

[varmint]

Soundguy- I am in accord with you- heating and cooling this thing from 50 to 200 and back on a constant basis just doesn't seem like a job for a glue. On the other hand, I know they build high performance aircraft with adhesives... I may have found a local TIG welder who'll give it a try? Worst case is I have some recycling to get rid of.

 

[Egon]

The manufacturer tells me: A) they can't/won't rebraze it, B) heating it to weld will cause more problems, C) my only hope is epoxy.

Chances are the manufacturer does not know what he is talking about??? ehh

 

[tlbuser]

Glue fixes tend to fail when you need them... I'd hate to be loosing oil out of an oil cooler because an epoxy scab cracked as the base metal it was attatched to expanded or contracted from heat/cooling at a different rate than the scab did.
soundguy

That's why you need to find the right sealant for the job. Not all "epoxy scab" patches are oil resistant or flexible or..... lots of neat stuff out there.