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Look what I found, 295 Head

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jlaird

jlaird

Great Pumpkin
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Looks like it was repaired at one time. However, it was run for an extended period after the repair and it looks like it held.

Intresting what a good man with a welder can do.
 

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Jack - was it 'stitched' or just cold welded?
 
Looks like cold welded to me Tony.
 
Ok, you experts out there need to comment for me. Is this an acceptable way to fix the problem or is there a better way or should I throw this head in the trash?

Remember now I do not race Miss Agatha, she is just for fun around town.
 
Jack - if a pressure test says its good, its good!
 
tony barnhill said:
Jack - if a pressure test says its good, its good!
Click to expand...

There ya go, have them run the pressure check on the high side, if it doesn't fail don't worry about. Cast iron welding is a art form, not many even try it, when I need it done I use Indy Cylinder head in Indianpolis, he's my be the best in the world at it, it ain't cheap, it normally for me only reserved for race head that repairing them is cost effective, but he repired a for for me, and they never gavew any trouble. You're going to have to deck a good bit off that head anyway for use with your 948 engine, so you will clean it up a bit. Go somewhere good to have it tested, ask your local racer buddy, machine shops ain't all alike, ask Tony about the guy who magnfluxed some cranks for me and him.

A couple of thing have to happen when you weld cast iron, first off you use a cast iron welding rod, and the head has to be normalized, mening it heated up in a oven, oh and done by someone highly skilled in doping it, it ain't as simple as just grabbing the mig welder and having a go at it, if that's what has happen there, then the repair will fail.
 
Hap Waldrop said:
machine shops ain't all alike, ask Tony about the guy who magnfluxed some cranks for me and him.
Click to expand...
Tell me about it....one shop said they were good, the other pointed out where they were cracked.

But, Jack, be careful & don't let them call a casting 'crack' a crack.
 
Understand Hap. I must have another .036 taken off the head, considering what has already been removed to keep my compression between 8.5 and 9.

Thanks guys.
 
Oh, thanks. Wondered about that.

Hope it was done professionaly and I guess with that note it may have been.
 
I've seen cast iron being welded. Hap is rite it is an art. I had a pitman arm on a very large power hacksaw fix ( i dont think calling it welding does the performance justice) defintly art.
 
tony barnhill said:
Hap Waldrop said:
machine shops ain't all alike, ask Tony about the guy who magnfluxed some cranks for me and him.
Click to expand...
Tell me about it....one shop said they were good, the other pointed out where they were cracked.

But, Jack, be careful & don't let them call a casting 'crack' a crack.
Click to expand...

Maganfluxing is only as good as eye looking at, plain and simple, I look at maybe a 100 cranks before I did it on my own, in the case of the cranks you sent me, me and kenny jaskson did them together, on aircraft magnfluxing troth .

When it comes to head, here's what I recommend, clean degrease, the glass bead blast the head, there is no possible way you can magnflux past carbon deposits, but either way you want the head bvack to the bare metal, and that point you can magnaflux a head, and only then, but a way better test procedure is pressure checking a head, thats the only crack test any head I'm working on gets, that real world/conditon test for cylinder head. Jack we got some really good shop up here to put exhaust seats in that head, you'll need new guides as well, valves and spring are cheap, so what the hey. Plus on your end, forget the froum ballbber, you need to cnfirm you piston deck height and dish volume, than you can tell what amunt needs to decked off the 295 head to get the compression ratio to where you need for a 948, this is not a job for any yo-ho.machine shop, if you have a good race shop down there maybe, but even then if thay are unfamialr with these heads and our guide clearences that still screww it up. I install my guides get all that right, then take to my buddies at Dover Cylinder Head and they put the seatrs in for, me, while threer i get them to cut the seat with 30-45-60 seat cutter, get my valve hieghts where I want them, then deck it, than I hand lapp the valves in and mask, paint and assemble, of course all valve are wieghted on a rimac, and seat pressure set to spec. Most machine shop just don't bother to do it right.
 
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