Chipped Valve, Oil Consumption & Head Change
Some 6 months ago my 156 1.8 TS CF3 gave up the ghost. Firing on only 3 cylinders it had been using vast quatities of oil in the 8 or so months previous that I had had it and would misfire at sporadic (but fairly rare) intervals. I compression tested it and with 0 compression on cyclinder 2 I decided to get a new one and investigate the problem when I had more time.
Today I finally got around to taking the head off and the problem is immediately clear. One of the exhaust valves on cyclinder 2 is chipped in 2 places and doesn't seal. In addition every valve in every cylinder is caked in carbon deposits from the heavy oil burning.
Now I have another head, taken from a 2ltr CF2 GTV which I intend to replace this with, however since this is my first time attempting this I have a few questions I'm hoping you guys can help with.
1) Whats the likely cause of the chipped valve? Could the massive carbon deposits cause it?
2) Given the vast oil consumption and the massive carbon build up in every cylinder what should I be looking for as the cause of the oil getting into all the combustion chambers? Piston rings? I intend to fill the 4 pots with petrol tmrw to check for leakage past the pistons, will the be sufficient to eliminate the bottom end as the source of the problem? I cannot immediately see from the head any source of the problem, theres a lot of oil everywhere but I figure mostly thats from me moving the head around. If I can elimate the bottom end as the problem that would do me as if its head related I should solve the issue with a new head.
3) Skimming. Is it nessacary if there hasn't been a head gasket failure?
4) Cleaing the surfaces before fitting a new head gasket. Whats the best way?
5) CF2 and CF3 seem to have different head gasket sets, the CF3 ones being more expensive. Whats the difference?
6) Anything else I should know before I tackle this? I have a reasonable experience of DIY car mechanics but this is the first time i've delved into the oily bits!
Thanks in advance for any help!