The only success I've ever had with locks is by drilling them out. Once I've drilled enough to get a screwdriver in, I then force the lock. You need to be very careful not to damage the surrounding panel.
Other options to try first might be checking every other key you can lay your hands on. Or getting a locksmith to open it then they can either make you a new key, or reconfigure the lock so it's keyed the same as one of your other locks.
NB, the only reason I've had to drill out locks is because a couple of spare parts car wrecks I've bought have had incomplete sets.
Thanks for the tips. Ill give the drill a shot not happy to use the grinder with potential sparks against the checker plate. As stated I have a new set of locks should have replaced them earlier.
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Keep your eyes open so you can see where you are heading
Sorry most probably too late for advice - but it may assist someone else.
The barrel usually will knock out very easily (unfortunately from the inside) when lock dismantled. In your case you have little option other than to drill out barrel and replace entire catch.
There are only a few combinations of keys in Australian caravans - mainly supplied by Thetford and Dometic. Lost Keys are readily replaced at caravan parts suppliers by quoting number engraved on lock face.
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Possum; AKA:- Ali El-Aziz Mohamed Gundawiathan
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