Cheddar/GRS Tram Piston Gland

[Chris Cairns]

Took my tram to a Garden Railway meet up today but it was failed on shed due to a major steam leak. I found that the gland collar was loose on the left side cylinder and once home confirmed that there is an 'O' ring behind that collar.



Just wondering if anyone here has experience of repairing these glands. An old posting on another Forum states that the collar was just glued back on but did not specify what glue was used. I do still have a bottle of anaerobic sealant that came with a Cheddar Models marine engine kit and will try that when I have time available to strip the tram down to degrease the gland.

This is the good cylinder on the other side.



Chris Cairns

[Big Jim]

Try having a chat with Loctite tech services, I think they are still based in Hemel Hemsted. I have found them very helpful in the past when I wanted some adhesives to repair various bits of old vehicles.
I think they are used to strange questions by now.

Presumably you want something that will stick well in use but can still be broken if and when you need to change the O rings?

[Chris Cairns]

Thanks for the reply Jim.

The response on another Forum confirms that this gland collar should be an interference fit (which it obviously is not now) but not to glue if possible. So I need to find some method like using a wrap of PTFE tape to keep it in place but still, as you point out, removeable if that 'O' ring needs replacing.

It will need to wait its turn in the workshop as I'm planning to attend 2 exhibitions these coming weekends to run live steam and need to sort out 2 different rakes of stock before then.

Chris Cairns

[Big Jim]

PTFE might be your answer. Another method might be some very thin shim brass or copper as a wrap to enlarge the male part of the joint. I think KS metals used to do a pack of incredibly thin brass as a mixed lot. One of the bits in there was almost fag paper thickness.
One thing we use in the Motor trade is Hylomar, or instant gasket. One of the types is a non setting sealant that does allow dismantling.

Sorry to just throw untested ideas at you, I hope you get it fixed.

[Chris Cairns]

Having some time available I decided to degrease that gland then fixed the collar using some semi-permanent threadlock.

However a run on blocks using an inspection mirror confirmed that it was not the gland that was leaking, but steam passing between the cylinder & the backplate. So no option but to carry out a strip down to access the cylinders.

I could not find any fault with the cylinder(s), and the wheels & coupling rods were also free running. Honed the back of the cylinders and oiled everything up. A run with the skirt removed proved that it was working again although there was still some steam leakage between the cylinders & backplates. Put the skirt back on and another run proved that it was still a bit sluggish with constant slow running.

At the recent Dundee show I picked up a bottle of Cheddar Models steam oil so decided to give it a try. Success - the loco was back to its very fine control for slow running.

So it seems to favour using the darker coloured 460 steam oil.

Chris Cairns