That's my 2 cents, not as a journeyman welder, but just a guy who has tried a few things. I have tried to find two reports about the use of the process being contained somewhere in my trade journal collections, but I beg your forgiveness, I haven't found them and it would take too long to continue the search - although I know they are there. I'll take the time to come back and post how it all went. With regards to the low temp aluminum solder Your vetran welders mentioned, it does work well for soldering nail holes in beer cans, but I am unsure that You will have sucess on a 300 engine block with it. Once we got it in the shop, we found a section inside the lifter valley that had been treated to a grinder. It is a tricky technique to learn and not many facilities offer this service anymore, but when done right it works. Anyone with an inverter could do the job on site, but I would think the cost of this would be far greater than taking it to someones workshop.
Some heads, such as Ford 2. You will end up with an outer edge of the puddle that has a high silicon concentration, and therefore crack prone. Next step was to take a torch and get the area real hot. Also make sure you mix it really well. I used a hardened drill bit and cutting fluid.
Perhaps you could get a friend to help with presentation of photos and text, as your skill would be much in demand, because more and more car parts are being made of alloys other than steel, which is much more forgiving in treatment. Volvos have cast iron blocks as far as I know. Read more about this repair on our Blog: How-To Guide: Step 1: Before starting work on the repair, make sure the damaged area is thoroughly cleaned and free of grease, oil and dirt. Six months later my tractor doesn't leak one drop of water in the oil and it has run as good as new. But I know some welders who swear by 5356. This is a real solution to a problem that many restorers and hobbyists have faced. But only the portion of the spline where the crack was.
The fellas have covered everything here. But it depends upon the power supply and if so you might try striking the arc. Cracks do not necessarily mean a cylinder head has to be replaced. Good luck with your repair. Just think of the possibilities.
I have repaired cracked up motorcycle trannies and cases with it, intake manifolds, etc. Cast iron can be welded using an arc welder with cast iron rod. This is a business transaction and your present mechanic may have made a misdiagnosis. The heat cool cycles should not be that extreme. These extremely hard particles make up 4% of the coating and form a multitude of adhesion spots where oil can collect.
I concluded that it's cheaper to go find another block from the same year and rebuild vs. Stop, clean it up again only to have more oil and the other crap that often accompanies welding cast ally appear once you start welding. Never gas welded or soldered. Jefferson has also written 5 books and produced countless videos. Once the hardener begins to harden inside of the resin, the epoxy forms into a solid weld inside and around the damaged area. Brazing with an oxy-fuel torch would be my first choice of a do-it-myself fix, otherwise a metal-filled epoxy.
We won't know how it turned out until I put the engine in the car and drive it for a few thousand miles. Do not tell the second mechanic what the first mechanic found, let him find out for himself. Second choice is to weld it with nickle rod. Devcon makes a repair epoxy for aluminum that has to be machined once it sets up. The spray welding technique has been around for about 40 years. The process sounds harder than it is- locate the crack and mark it We used the SpotCheck kit from Maganflux , drill a hole in the block, countersink the hole, tap the hole with a special tap, insert the pin, and then drill another hole right next to the first, while overlapping the first pin, and repeat.
As for repairing them that way, most times it isn't worth the cost. Thanks for the input from everyone, the job worked out and I saved my brother in-law 9k on having to buy a new block. Plastic tank can be plastic welded if there's still some life in the plastic. Today we have epoxy but everything is thrown away. He used the tape only to hold it until it was dry. We built a Fixture to hold all the parts together.