Garden Railway Forum

Welcome Wednesday - Take Two (of ???)



The fabulous team at Mamod received my broken (by me) brand new quarry loco on Monday repaired it and turned the wheel centres down to give me deeper flanges so that it wouldn’t bounce off on my LGB point frogs, as they did for my Boulton, and it was back with me this morning - Wednesday.

Now all I need to do is learn how to use it. At the moment it’s either struggling to shift its own weight or charging off like a scalded cat and derailing! The only way I seem to be able to tame it is to use my Boulton to hold it back.

Tips and hints would be very very welcome.

I’d like to fit a Caradoc type water level indicator; there is a boiler level plug and I think it would be possible to replace it with a valve - what threads do Mamod use?

I couldn't help you on the boiler threads, but as for the running, your video gives me the impression it just needs a good few (8+) hours of running in.

Mamod's have always had 'interesting' running characteristics, but to begin with I think Aaron is right - it needs to be run in before you begin to see its true running characteristics.
By the way - your railway looks like an excellent candidate for an Inspectors visit - I can see a great yarn developing if he paid you a call!

Lonsdaler wrote: ↑Mon Apr 15, 2024 1:57 pm By the way - your railway looks like an excellent candidate for an Inspectors visit - I can see a great yarn developing if he paid you a call!

I agree, though he'd better check all restraints and fall hazards, especially after what happened to Poor Bill this weekend!

I received my Mamod Quarry loco after replying to your earlier Facebook posting, and looking at your video again, I see you have the same problem as I found on mine - the piston rod glands are too loose.


Do these glands up finger tight so the 'O' ring is being slightly compressed against the piston rod.

Not in their lubrication instructions. Turn the wheels until the piston rod is fully extended then put a drop of steam oil on the piston rod against that gland. Similarly turn the wheels until the piston valve rod (above the piston rod) is fully extended rearwards then put a drop of steam oil on the piston valve rod. Turn the wheels until the piston valve rod is fully extended out the front end of the valve block then put a drop of steam oil on the front end of the piston valve rod.

The boiler plug on the boiler backhead is the standard Mamod thread - 1/4" x 26 BSF

The pressure gauge on my Mamod Quarry failed on its first run on blocks. Still waiting for a response from Mamod.

Chris Cairns

Thanks Chris
It’s back with them again now. Steam chest on the left pouring steam out at any psi >20. I suspect there’s a warped or inaccurately machined surface in there somewhere.
One piston rod gland came out mid run.
The thing that baffles me is that it was fine on blocks but as soon as it was on the rails the problems started.

Nigel’s Leaking Quarry Loco

That's disappointing Nigel. Hopefully they will sort it out promptly.

Chris Cairns