thought I'd give you all an update to raise your spirits slightly if you are having RR troubles.
Got the head off, massive crack between the valves on cylinders nr 4 and 5, luckily I had sourced a skimmed and pressure tested head from ebay for the princely sum of £80! Too good to be true? You bet it was, but I'll get to that. I also splashed out £22 on the valve setting tool - totally worth spending the money on I now realise.
Got the head back on and all seemed to be going well, tightened the cam down slowly and evenly across all the bearing covers so as notto bend or stress it too much - this it would turn out was the least of my worries. Having eventually realised the cam chain tensioner was not fitted correctly I overcame that drama and fitted everything onto the engine with a nervous anticipation. Bled the diesel through and turned the key for it to not even try and fire, let alone start.
Eventually it coughed and spluttered a little but wouldn't start. This was not the desired result after 3 days off work to rebuild the engine - I removed the rocker cover to find the cam drive sprocket had slipped and was about 10 degrees out, oops! On arrival the cam setting tool was put to use straight away and the marks I had made were actually not too far off. Again with the refitting of the rocker cover and inlet pipes, key in the ignition, still not starting but the farty splut spluts were more encouraging.
At this point had I noticed the pin for setting the crank position was loose in the flywheel and required a joint effort of me wiggling the crank with a 22m spanner and swmbo pushing and wiggling the setting tool until it found its way all the way into the hole I would have been a happy man, however it was not to be.
We were now cooking on gas and nothing could stop my amazing engineering prowess as I reset the cam for about the 7th time. Refit rocker cover, inlet pipes and turn the key... Also don't forget to remove the setting tool or spanner on the crank! Attempt nr 8 with the key turning part of the process.
Oh my word, running on 2.5 - 3 cylinders it made an impressive smoke screen that would have hidden a battle ship! Accompanied by s loud knocking noise. My heart sank slightly more than I thought it was possible for it to go as I realised the timing was still wrong and valves were hitting pistons. Cue grown man crying like a baby.
'Maybe I got lucky and they aren't bent' was the deluded thought process I went through. Having now realised the setting tool needed the wiggling I mentioned above hte engine was locked in position and you guessed it, cam reset, rocker cover, inlet pipes, remove setting tool and spanner, turn key. Wow, a more predigious and vast smoke screen has never been produced, definately valve issues so nothing for it remove the head - again!
Luckily in the process of stripping the head I noticed that the centre bearing of the cam had all manner of marks and scratches that weren't there before, turns out after machining the head the oil ways hadn't been cleared of swarf properly so I am now awaiting the arrival of a replacement cam and a new valve compressor (BMW valves are deep in hte head so you need a longer reach pushy thing to remove them!).
Moral of the story - buy the right tool for the right job or avoid P38s? I'll let you know once I get it running as to whether all this character building was worth it...