I need a product to fill pits in an aluminum head

I agree with Kevin, the JB weld 24 hour set (not the 5 min stuff) should work fine. Rated to 600 degrees, we use it a lot in our powder coating shop and have exposed it to over 500 degrees without failure. I know a head surface is a different story but there's no reason why it shouldn't hold up. I would just make sure the areas that are pitted and are going to be filled are at least sandblasted so all the crap is out of the pits, prep it good with some brake cleaner and fill it. If you heat it up a little with a heat gun before mixing it, it will flow out better into the pits when applying it. Don't apply to much heat or you will get air bubbles in it. JB's some good stuff if you apply it right and let it set up when your suppose to!

 

The JB im sure will work just fine
The closest iv come personally to using it like this was also on a flathead.

I bloke a chunk of block out on the deck …. head bolt hole into the cylinder.
I JBed it back in and put the heads on …. No problems. It would still be in there if I didn’t build a fresh motor.

 

Me too

 

I have used http://www.belzona.com/products/1000/1511.aspxused with good luck, I can not tell you the price as I acquired some from a friend that had access to it.

 

Can't beat High Heat JB Weld...

http://www.jbweld.com/product/j-b-highheat/

 

All the pits I'm seeing are where there is no gasket anyway. Looks like you have good surface everywhere the fire rings seat. Do you really need to do anything?

 

Porosity and inclusions? Any chance you are a foundryman?

 

I've used Marine-Tex in some pretty demanding situations. It's available in most boat shops. You might look it up online and see if it fits the bill.

 

As stated, the JB has a higher heat rating than the Devcon. I suggest looking into the high heat Lab Metal, often called Pyro-Putty. Eastwood sells it.

 

I have Lab Metal but never used it in this app. It is some neat stuff. I have done what Kevin has done using JB to guard against porosity. Car has somewhere close to 15K on it with no issues.

 

Used J-B Weld on my SBF cast iron heads.Same issue/ No problem

 

I have a pair of Evans block letter heads worse than these. I've been really concerned they were just junk. But....

....if this is the results Kevin has experienced its good enough for my junk!

Thanks Kevin (and several others) for the real-world experience, it beats data sheets any day and I never would have considered JB would save these!

Sent from my DROID device using the TJJ mobile app

 

What did you wind up doing? Have an update?

I'm thinking of doing DevCon on some stock 34 aluminum heads were the water ports are corroded a little.

 

Any reason i couldn't use the devcon or jb weld to fix the water neck tapped hole of a old set of navarro heads?

 

Midwest Cylinder Head, the experts at welding anything cast.
http://www.midwestcylinderhead.com/index.php

 

This man has the correct answer. MarineTex is JBWeld on steroids. It is intended for exactly this type of repair. Available in black or white.

Those surfaces do not see combustion temperatures, BTW. They will be clamped nicely by the head gasket. I would consider using copper gasket spray on both sides of the gasket.

Of course, this is a necro thread so all bets are off as we do not know what OP did.

 

There was a link to this thread from another, so I thought I'd let you all know I haven't done anything to these heads yet. I haven't found a welder, and haven't tried any epoxy.

The car these are destined for might see some progress in the next year, so I hope I'll find a way to repair these soon. I'm probably going to try welding a bad spot first and see if it blows through.

 

My heads were about like yours...

I had them welded up and so far so good... After surfacing and putting in a larger cam I had to cut the valve area a bit deeper on each cylinder.

 

The last thing I would do in a case like this is welding. There are so many good epoxy type products out there it is simply not worth risking your vintage stuff. I had a set of Edmunds heads that were in about the same shape, and I used the "High-Heat" JB Weld to fill in the pits, even though it was probably not necessary. It worked fine.

 

I have done this in the past. Getting to spotless clean is the key to good repair . It is porous as a bar of Lava soap . I always would have a scrap piece of the material I was repairing and file on it for a bit . Gather up the shavings and mix them in with the product I was using to make my repair with . I have done many Harley heads , chipped , broken cooling fins , chips out of head gasket surface , no issues with the repairs what so ever .

 

Pyro-Puty
https://www.aremco.com/ceramic-metallic-pastes/

 

You can't go wrong with this stuff. you can machine it after it sets up.
http://www.aircraftspruce.com/catalog/cmpages/aluminumfilledepoxy.php

 

Many stories around here about someone pulling a cylinder head and finding this stuff inside, because the head had broken clear in half many years before:
http://www.pratleyadhesives.com/diy-adhesives/pratley-putty-original

Pratley's is South Africa's answer to duct tape.