I need a product to fill pits in an aluminum head

I've got a pair of Harrell heads for a flathead Ford, and they are corroded on the underside. I was thinking they'd have to be welded, but old aluminum castings were notorious for poor quality materials. Many stories of porosity and inclusions making the weld pop and blowout.

I'm wondering now if there is any other non-weld material that will work instead. Some magic goop to mix and apply. Most of the corrosion is around the water port holes, and kinda near the stud holes. But there are a few that go to the edge of the combustion chamber a little. Truing the heads after fixing is not a problem.

Has anybody used a product exposed to combustion heat with no failure? What was that product, and what did you use it on?


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I think anything not fusion welded in will have problems. Due to thermal expansion, anyting that relies on adhesion is going to have problems unless it has exactly the same coefficent of thermal expansion. Or something that has good flexibility, but then it would not work so good for clamping force and sealing.

 

There is a product race motor builders are using now for filling in stuff … exhaust ports and such.
Sorry I don’t know the name but iv seen it and its said to stand up to heat and fire.
It may be the same stuff they fill dry blocks with.

Like kev said JB would also work

 

Well, there are a lot of pits for a product to bite into. But the rest of your argument makes sense.

 

I found this stuff. The Resbond is supposed to be good to 2300 degrees. Anybody use it?

http://www.ruffstuff.com/pages/kits.html#epoxy

 

i'd try something long these lines, http://www.youtube.com/watch?v=Bu2bq9ad0e0

 

I also have used J-B Weld and it is very durable.

 

J b weld...

 

Look up Loc***e and Devcon products. They're carried by MSC, McMaster-Carr, Tractor Supply, Graingers, etc. Maybe even Ace Hardware. The 2-part epoxies set up hard and we've had no problems machining it smooth and drilling holes in it.

Bob

 

There is a product called Devcon that is made for filling pits in aluminum castings. I used it in my air cooled VW head porting days. Good stuff.

 

Beat me to it, I'm a slow typer!

 

I have soemthing else to ad. This works and works well.

If Kevin's toaster isn't proof enough then I have also used it on valve in head engines with good sucess as well. They do also make a JB weld that is specifically for aluminum.

 

I used JB weld on a late model intake with the same problem. It worked great.

 

Late model 3.1-3.5 GM heads get like that If the coolant isn't maintained properly.
I've used JB weld with no complaints or returns. Just blast the crud from the eroded spot. Apply the JB and re-surface head. The stuff is inert and lasts longer than the parent metal.

 

JB Weld makes a specific high temp goop that would probably be the stuff to use, although it sounds like the regular one works too.

 

I think that is Devcon, which others have mentioned - this is what I use....

 

Devcon epoxies are JB weld's big brother and the steel putty will hold up when used to repair gouged bedways on boring mills. They have an aluminum specific product too:

http://www.devcon.com/products/products.cfm?brand=Devcon&family=Aluminum%20Putty%20%28F%29

 

Check out products made by " Devcon "

 

Woops, I didn't read the post above mine.

 

Find a good race engine builder, they'll grind out areas, and weld them up. Followed by a quick deck of the heads. We've welded up stuff a lot worse than this, no problem.

 

Will milling the head .010, .020, or even .030 clean it up enough to seal on the head gasket? Then you could relive the block to get the compression ratio back down to what is was before milling the head. On the one hand the higher CR that results is better, but all high compression heads already sacrifice flow for CR. By milling the head we gain CR but loose on what already is a low flowing design therefore, relieving the block gets the flow back that was lost in milling (and in the original design of the aftermarket head) If your going to relieve the block do it all the way to the cylinders, from what I understand, partial relieving doesn't do anything for flow.

Just an idea.

Kipp

 

I think your in for a rough one, epoxy is great for alot of things, but not on a deck of a head. To weld those heads I bet you'll have to grind out to about 3 times the size of the affected to get to any decent material,maybe.

 

Welding old sand castings is (ALOT!) easier said than done.
Plus heat treat will be lost

 

Don't think so. That one little spot at the top of the valve pocket in the pic would probably take .100" to mill out. Then I'd be cutting a lot into the dome and valve pockets to get clearance. Probably the same $$$ as if I'd just welded it.

I'm thinking now I'll just have to find a local welder willing to give it a try. I notice most of the fillers posted and linked are good to maybe 500 degrees, except for the Lab Metal. And many of them cost a bunch (maybe an hour's worth of welding time).

Thanks for giving me products to research, and if there's any more experience or products let's hear them.

 

Theres a small tube (grey) at auto parts stores here it looks like grey clay.you mix it together and it dries hard as hell.it's for aluminum.I used it on a sbc intake

 

I've seen a product used in aluminum foundries to fix up less-than-prefect cast parts. If I can dig up the name of it at work, I'll post it.

Bob

 

And it was the best REAL WORLD solution. Sometimes we overthink these things.