Re: Timing chains

[PGAHOWELLS@domain.elided]

Hi Ian etal
I did get some further information on this topic.
Apparrently the tensioners push out under oil pressure. They are on a ratchet
so click out step by step until they reach the  raised lips of the backplates
which stop any further travel.
From that point on the chains are running without any further tensioner
movement to take up the slack.
Then they will start to slap against the guide plates and this can be heard.
Thats when they definitely need a change. It is a sound I have yet to
experience.
Additionally, I am told one can remove the right cam cover and peer down to
observe the amount of extension of the top tensioner. I haven't tried to do
this yet, because I have no slapping sounds, but I shall have a look when the
spring comes and its a bit warmer.
I still think it should have been listed in the service schedule, to check
position of tensioners every 12000 miles.
I have also heard that oil pumps for the Saab engine will work in a Stag, but
put out a higher pressure.
That will not be good for the rubber faced tensioners it seems to me. 
The Stag engine is such a very nice engine to drive, so smooth and very
powerful, its a pity that this timing chain thing is such a worry on an
otherwise superb engine. (Thats when you have made sure the block is clear of
sand and scale, and the heads are OK and on right, and its all been assembled
with the correct torques and run with a clean radiator and correct
antifreeze).
Peter H