Welding cracks in cylinder

Found cracks in the cylinder on a 6 hp Fairbanks Morse H I am restoring. Two are cracked around the point where the head bolts attach in the water jacket. The other one starts one side of a where the bolt attaches and goes around the ignitor to the other bolt. The cracks are only in the cumbustion chamber, not where the piston runs. The engine was in a fire, but I don't know if that was the cause of the cracks. I would like to weld this. Does any one have any ideas about how to go about this? In total, there is likely about 8 to 10 inches of crack.

If it was me I'd drill a hole at the end of the cracks. Grind a V in the crack, (both sides if you can), and them get some nickle welding rods and weld it up. The condition it's in, I don't think you can hurt it.

Be careful not to warp it though by getting it too hot.

A fellow I know has done some welding on cast iron for me. There is a lot of debate on this topic in terms of pre heating and post cooling. He has welded some high stress areas for me (rocker arms, garden tractor axels etc.) and all that he does is pre heat, weld with nickel rod and let it cool on its own without quenching it etc. So far I haven't had one of his welds break on me.

CJ Winslow - the kid with a lust for rust.

Thanks. That's what I was thinking of doing, but I thought there may be a better way.

Merlin...If it were my engine, I'd V it out with a grinder and weld it up with a wire feed welder or mig....weld it with low temp,no preheating or slow cooling...this method works better for me in places that are thin and no/low stress areas like water jackets...Oh by the way...when you're done trying the Nickle rod on thin areas...and have an engine full of "burn through holes"...the wire feed works good to fill in the holes too.....Thank God! Mark Congden

I've read about a cold repair process called "metal stiching", where you drill and tap the crack and insert special studs that interlock.

You can look up metal stitching on the Web. Personally, I don't like to cook old iron. Sometimes it ends up in worse shape than when you started.

Take care - Elden

I'm not sure how thick it is, but I would think it is fairly thick. Is there any thing special about the wire or the gas for wire welding. Cold welds wouldn't work here.