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I am looking for recommendations of a vendor who could repair the cylinder head from my Series 80. It has a cracked and bulged section (about 3″ diameter) resulting from water frozen in there one winter. It looks repairable to me, but I know that cast iron welding is a tricky art.
What experiences, good and bad, have you had with cast iron repairs? I’m in Oregon, so I’d prefer to find a vendor on the west coast. Does a repair like this make sense, or would it be better to just look for a replacement head?
Hello Dan,
Cracks in cast iron are one thing, but bulging with cracks are another.
As you point out, cast iron is hard to weld. You cannot just take an arc welder or oxy-acetylene torch and lay a bead of filler on the crack. This would be like concrete in Iowa. Cracked, and going to crack. The Heat Affected Zone right next to a weld in cast iron will cause a failure right next to the old crack. It is virtually unavoidable due to the microstructure of cast iron, unless the weld is done under the correct conditions.
I had an 8 cylinder head repaired by a firm here in Iowa that specializes in these repairs and take their work very seriously. I wrote a feature article on this repair a couple of years ago…it is still available in the archives on the PAS website if you would like to read up.
The key is getting the whole cylinder head up to temperature in an oven to do the welding…not just heating up the area to be repaired. And I am not talking 200-300 degrees, either. Another key is use of the correct filler material. It is best to use filler material of similar alloy to the cast iron that is being repaired. Once repaired, the temperature needs to be ramped down slowly in controlled conditions. The cylinder head being repaired also needs to be clamped correctly to prevent excessive warpage during the thermal cycling.
Magnafluxing to identify the extent of the cracking and damage is also important, too. You can’t just repair the cracks the you can “see”. There may be other microcracks in the head, just waiting to open up, possibly radiating out from the visible damage, or possibly in another area.
Pressure testing after the repair is important also. The head should be sealed up and compressed air applied and possible pressure loss or bubbling in a dunk tank detected.
Building up of the water galley openings can also be done at the same time so that you head gasket seals completely.
The aesthetics can also be dealt with also. My head only had hairline cracks, but I was shown an original ’50’s Chrysler Hemi block with a softball sized hole in the side, right across the cast in part number on the block. When I returned to pick up my head, the Hemi had also been repaired, tested, and re-textured. Experts had gone in with a die-grinder and re-textured the repaired area such that you could not detect a difference in the texture and could not see the repairs other than a tonal difference in the filler material. Once painted, these repairs would be invisible.
I’m sorry that I don’t know of a repair source on the west coast, but I would be glad to send you the contact information for the shop that repaired my head in Iowa. I would absolutely use their services again if needed.
Good luck with your head repair. Hopefully, I have given you some ideas and raised some questions for you to ask a prospective repair shop.
Happy Motoring,
Chris Diekman
Dan,
Try Lock-n-Stitch in Turlock, CA (south of Modesto on US 99). Their entire business is casting repair. They are (or were, at least) the vendor of choice to Waste Management (trash conglomerate) and the Northern Calif Caterpillar distributor. Their process is thoroughly explained on their website, http://www.locknstitch.com/
Perhaps 8 yrs ago they repaired my Series 80 block, which had a couple of small valve seat cracks + a monster crack that went from the #2 exhaust valve seat across the deck and into the #2 bore to a depth of 2-2.5 inches. They strongly urged me to NOT sleeve that cylinder if at all possible (I didn’t). They pressure tested the repaired block to 30 psi, so they said. I had to use a coarse hone followed by a fine hone on #2 cylinder bore. I used the same pistons, and used fine hone on the other 5 cylinders, then new rings, of course. I have at least 2-3,000 miles on the engine with no indications of further cracking. Including hard seats for exhaust valves, the bill was a little over $600, but that was 8 or more years ago–a pleasant surprise.
They are true professionals, and casting repair is ALL they do. I’d use them again in a heartbeat.
When planing your S80 head, take just enough off to make it flat. The mating surface of the head was arguably too thin from the factory, and the head has probably been planed half a dozen times over the years. Be sure to use a dental pick to get all the crud away from the studs where they emerge from the block, so you get a proper seal. Suggest you use a copper sandwich gasket (rather than a composite one) and give each side of the new gasket a couple of coats of aerosol gasket copper (I use Permatex’s product), following the directions on the can.
Good luck and please keep us posted on the results!
George
Lock-n-Stitch repaired a crack in one of the heads of my 1933 V12 PA several years ago. The crack was along the top surface of the head and extended around the back edge. After inspecting the crack, they suggested that it appeared to be the result of water freezing in the head. The quality of the repair is excellent.
Most recently, I used Lock-n-Stitch to repair a crack in one of the exhaust manifolds. The crack was next to an older repaired crack. The car will be back in operation shortly and I anticipate the problem will not occur again.
I continue to be impressed with the quality of work from Lock-n-Stitch.
Rich L
Rich, thanks for posting-good to hear your car is close to fixed. I loved it at Temecula.
Dan….we have a cast iron repair shop here in Washington State…just north of Seattle in Marysville. He also does excellent work….I can get his info if you would like…..Rich 206=240-9434