A little co-operation from the parts stores would be nice
After a nice, long afternoon nap while waiting for the storms to subside, I got back to work.
All that remained was breaking the head bolts and lifting that 90-pound beansucker off the engine. I wasn't exactly surprised by what I saw.
There wasn't much corrosion to speak of, but there was a lot of built-up scale blocking some of the head's coolant passages. The engine must have been running hotter than the temp gauge led me to believe.There was also an incredible amount of carbon build-up in the bores and combustion chambers:
Now that the head's off, the culprit is identified. here's the burned-up exhaust valve on #5 cylinder. There's a vacuum line on the intake manifold near the passage for #5, there must have been a leak that allowed that one cylinder's air-fuel mixture to lean out enough to cut through that valve like an acetylene torch:
Now that the head's off, I've relocated to the back yard, to the porch of the workshop out back. I would set up shop indoors, but the workshop is pulling duty as a storage room, piled to the rafters with crap because I'm too cheap to do mini-storage. At least I have a roof over everything now.
The cylinder head, balanced on a pair of sawhorses, was ready for final disassembly. As the bearing caps, camshafts, tappets, and valve shims came out, I placed them on a pre-marked piece of cardboard to keep them organized so I can put them back in their exact places once the job is done:
I did say this required some organization, didn't I?
As always, Murphy has put in his two cents too. To finish the disassembly of the head so I can clean everything up and replace the barbecued valve, I need a valve spring compressor. Unfortunately, and in spite of the prevalence of overhead-cam engines, two hours of phone calls failed to yield up a solitary store with the correct compressor available. I guess that tool manufacturers expect consumers to take it in the shorts from mechanics rather than tackle a simple valve replacement.
Oh well. I'll see if I can get the spring compressor tomorrow before work; I won't get all the parts I need for a few days anyway.