Merlin Maestro - Help Needed

[Beepilot]

I have recently acquired a Merlin Maestro but I'm having problems getting it to run. At this point I'm attempting to run it on compressed air and although it shows some signs of movement it almost immediately locks up. To me this suggests that the timing is wrong which probably is a result of at some previous time being assembled incorrectly. There is no adjustment on any the running gear or pistons or valve gear but solely depends on being assembled correctly. The only possibility I can see is that the pinning of the driven wheels can be out by 180 degrees i.e.they have to be pinned in the correct relationship to each other. I can also see that the original pinning holes which are clearly as original allow for one wheel crank pin to be 90 degrees in advance or retard of the other.

I would very much appreciate any help or advice from anyone who has actual experience or knowledge of the Merlin and particularly the Maestro assembley. This could be either pictures of both sides of a working Maestro with wheels in a fixed position or information of the crank positions in relation to the valve gear.

[jimmytrains_01]

Can I ask a question about the locos back cab sheet? is there a hole just above the buffer beam with a bras rod just protruding ?
if so this rod will have two notches in it they move your slide bars for forward or reverse, you can get it wrong the notch is set correctly for forward or reverse. They regulator is on a servo arm. The other way is a full rotation in the way of travel. Put water in it set fire, away you go.

[Beepilot]

Hi jimmytrains

Thanks for your reply. On my Maestro there is no protruding brass rod at the rear but I can understand what it does. My Forward/Reverse gear is activated with an RC servo which together with another servo activating the steam valve is how it would have been supplied new. I think the point you are making is that with the Forward/Reverse gear in the mid position there is no action from the steam cylinders so it does not run. Unfortunately that is not the problem with my engine as it fully engaged either Reverse or Forward motion. Thanks anyway for the suggestion.