Hi Kevin, I did not ask them to document with photos, though I can call and ask if they will. I found this Brodix video online, which I found informative. I wish Brodix worked on other products.
Welding Aluminum Cylinder Heads.
Sbaert, I have put 100K miles on the car in the five years I have owned it; the engine has run at 82C since I have owned her. Variation from winter to summer is 3-5C. During the first two years of ownership, I broke a fan belt, and she ran hot for about 15 minutes. Three years later the cracks in the head occurred. I can tell you the exact second the crack occurred, as I blew a radiator hose and overheated to 120C at the snap of your fingers. I thought the t-stat had failed, which I replaced, with no luck. A coolant test revealed hydrocarbons, which pointed to the head gasket. I thought that had failed since I had a slow coolant leak from right side #5 cylinder which I have been tracking for two years. I used a $45 cooling system sealant from Advance, which most likely I should not have. It sealed the coolant leak for almost two years until I brought the car to a Chicago winter, which seemed to damage that temp seal.
After dis-assembly, I see many coolant passages are partially or completely blocked with what looks like an opaque salt, which I suspect came from a combination of the sealant and electrolysis through poor bonding. I will add several additional electrical bonding straps during re-assembly.
Sbaert, I have not run MB coolant in the system, I have run medium quality domestic coolant. I will switch to MB coolant after this repair. She never has run low on coolant, in my five years of ownership, up until the time I thought I had a t-stat problem. GM Dex-Cool has not been in the engine. There is a measurable quality difference in domestic and MB coolant?
Hi Zeitgeist, I have taken a hundred or so photos for documentation for re-assembly, and did get photos of the head, but only before a local machine shop pointed out the cracks. After I found Rams, I hand couriered the head and cam, wrapped in blankets, in my suitcase, on the train, as train fare was $28 round trip, far cheaper than packing and shipping. I will call the shop in the AM to see if they can get a detailed photo of the cracks before repair. My photo shows discoloration to cylinder head #'s 3&4, where the cracks are. They are hairline, about 1/4" long, emanating from center outward to the pre-combustion chamber nozzle protrusion. I am in classes for the weekend, on Sunday or Monday I can post a photo or two. I used your posts and photos on your injector pump leak/fuel pre-heater corrosion coolant leak thread to help with the job, thanks so much for posting that valuable information!
Other symptoms included audible popping noises as the coolant reservoir cap released pressure, small white puffs of smoke during starting (did not happen often) where I suspect a drop or two of coolant leaked into the cylinder, and just very odd temperature variations after that hose blew/suspected t-stat failure. I mentioned before, she ran rock solid at 82C for five years with the one exception of breaking the serpentine belt over three years ago, and the recent problems.
Replacing the head option exceeded the value of the car. Repairing the head is worth my time and, paying for the repair and gasket kit, and taking the risk on the repair. I will update this post as I make progress.
Wade.