I am new here, so I would like to say hello : ). I have recently bought a S80 I, and got lovely package of problems
. Anyway, after misunderstanding with mechanic I decided to check why there is no compression on 2nd cylinder. The first guess was the burnt valve. It is indeed
the reason (see pics below)
I have my cylinder head under rebuild, but the expert told me to check the cause of the damage. He suggested that it can be leaking piston oil
rings. We have discussed possible scenarios:
I. Ignition coil malfunction (it was replaced by previous owner and he mentioned about some ignition problems)
II. Not enought throughput of the LPG injectors or mixer (installation form beginning of 2016)
III. Natural wear, material defect of valve (engine has 270 kkm)
IV. Piston rings leak, burned oil causing carbon deposit occur
What is Yours' bet? I would like to check carefully the engine before I replace the head. I tried with oil poured on piston's top to check for
leaks, but it is supposed to be unreliable test, as the rings can be clogged. Should I remove the pistons and inspect the rings?
The other thing is the sealing head cover liquid gasket. There is Volvo one (~50 $), Loctite 510 (25 $) and Elring AFD2000 (~ 15 $), which one
would You use?
The last thing I am concerned is that it is said that once the timing belt is pulled off it can not be reused, even though it is relatively not worn ( few thousands kilometers run). Is that true?
Best Regards
Mike