A while ago I posted that I had a worrying engine noise coming from the top of my 's' , and was advised that it would be worth checking the Cam chain.
The good news was that the everything looked as good as new at 115K, but thought that while the cover was off it would be good idea to change the chain guides.
Porsche Shop sold ne the top guide and new Cam cover gasket, apparently only the top guide is available separatly, the lower guide only comes with a new tensioner, or so I was told.
Removing the cover was easy, it was suggested that the fuel lines are removed, but I managed without.
I had no problems with removing the tensioner, remove the oil supply pipe first, be careful to recover the two washers, there is one either side of the pipe on both ends.
Compressing the tensioner was achievable with hand pressure and I used a section of wire coat hanger to retain it.
Changing the guide is a matter of slideing the old one off and the new one back on.
This is were my problems started.
First mistake - I didn't have a torque wrench for the hollow oil supply pipe and cam bolts at 10 NM and coulld not find the torque setting for the tensioner fixings, so used what I though was just enough, until it was all back together and found that I had an oil leek. I gave a cover bolt another turn, you guessed it the bold snapped at the thread.
Bolt from Porsche Guildford ordered and torque wrench purchased.
Second mistake - There are two lenghs of bolt that hold the cover, despite having pushed the bolts through a cardboard template of the cover to keep thim in order and having the bolt with me when ordering the next day I ordered the wrong one, correct bolt ordered.
Now in possession of a torque wrench though I would check the tentioner and oil pipe fixings.
Third mistake - I had over tightended the two tensioner fixings, the threats in both holes stripped out. These are tapped into the aluminium head, the other fixings look to have a steel insert into the head.
Heli Coil kit purchased from Machine Mart £22 or there abouts, hols drilled (a little worrying) head completly covered to prevent any swaff getting into the moving parts, holes tapped, coils inserted.
Forth mistake - "If you thought the last one was bad" Having put it all back together I had removed the rags preventing anything dropping down the oil drain holes. I though it would be a good idea to put the tensioner bolts back into the head so I didnt loose them, well I did loose one, down the centre oil drain hole.
No amount of probing with magnets etc proved successful so there it stays. Two new bolts ordered from Porsche!!!!!!
It is now all back together, torqued up correcctly, the tensioner guide and cam gasket replaced, no oil leek and running perfectly.
I have been very honest with this report on my attempt to carry out this minor DIY job in the hope that others can avaoid the same mistakes.
I have some good pictures but cant get them load on the site.
Russ
