Thanks for the info and warnings.
I did push the screw in as hard as I could, but it turned freely apparently not engaging anything. However, it was possible to get the sprocket wheel off the cam and free of the chain, so the chain could not have been under tension. However, afterwards I noticed that the whole tension mechanism was loose and could pivot. It does not seem right.
It is possible to get the chain off, Jon, even with the tensioner applied so that is not a reason to say it was not correct. It would also depend on how well and how close the guides were fitted. The last engine I overhauled for someone, the guides were so far out of place that the chain was loose even with the tensioner applied!
Suppose that after the last time your engine tensioner was fitted, the screw was broken, it could be why it just turned but did nothing. I would like to see all the parts of the tensioner (stripped) in detail, spread out, and possibly from a few angles, and then maybe I can see if it is any good - you may be able to rebuild it correctly and re-use it. Or you could send it to me and I will check and rebuild it if it is any good.
Just in case I got a new tensioner from Simon and it has a different release mechanism. It has a clasp in the side of the mechanism, which releases the spring when turned and push the tensioner forward.
I am curious how to do that once installed in the engine? I do not recall a hole on the side like the one on the front where once the plug is removed you can get to the screw. I included photos of the new tensioner.
That tensioner is no use Jon, in a Murena or Tagora or probably any engine unless it has an access hole on the front of the case, as you would have to have the timing case off to release or apply it! The screw has to be accessible from the outside through the side hole provided by the plug.
With your warning about grinding the side of the gear or synchro ring I wonder what options I have. I already tried a new Synchro ring from Simon a few years ago and it lasted only 6 months. I need a ring that better fit the gear or a gear that fits the ring. But where can I get that?
The problem is the synchro cone and cone on the gear do not match, in size or angle. So when you fit a new one, it only just touches and as soon as it has bedded in, it will not work. The synchro cones you have, both old and new are not wasted as they are not really worn (look at the 'teeth' - a worn synchro cone has no teeth and is worn smooth) and can be re-used but you need a gear with the correct cone angle on the side of it. So either you have to get another correct gear, or adapt the one you have or possibly have a smaller cone made. One possibility might be to have the gear cone increased in size using the metal spraying technique to add material and then re-machine it back to the correct size and shape, but this would be expensive assuming it was possible. There is also the heat treatment aspect to be taken into account which may prevent this. I have been out of engineering too long to know all the 'ins' and 'outs' and there may even be a different or better way to do it now. You would need to speak to someone currently in engineering for better advice. However, I feel the easier way is to try to find a correct gear - it is not the cone that is the problem, it is the gear.
Roy
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