Cylinder end cap adrift.(piston end)

[Pendo Pilot]

My lines No 1 mamod has decided to blow the piston end cap off on one of it's upgraded cylinders. This is now a loose fit when I try & press it back in. It's like it's diameter is smaller than it should be. Any idea's on a glue or something that I can reseat the end cap with that will hold the pressure from it's upgraded.
Probably not helped by the fact I finally managed to stop all other steam leaks on the machine, guess it was the last weak link in the chain.

[Sir Clothem Cap]

Did you manage to fix it?

[Tobias]

same happened to mine on a old 2-6-0 i soldered it back but have not tested it yet but the piston sheared off of the end of the rod on mine and that is what forced it of

[DolwyddelanLightRail]

Britomart did that. Some locktite did the job!

[Crackingjob]

I have also ordered upgrade for the pistons on my Mamod SL1, like another post re dead leg lube...anyone got photos of fitting the upgrade???

[Chris Cairns]

These 'O' ring piston upgrades are only available from Dream Steam, and are provided with instructions. I have no experience with the Dream Steam ones, only the earlier IP Eng & Mike Chaney ones.

They are a development of the original IP Eng 'O' ring piston upgrades which were covered in this thread - http://gardenrails.myfreeforum.org/ftop ... -asc-0.php

Only relevant photo I have is a completely disassembled Mamod Cylinder & Piston assembly.



When you go to take apart the cylinder assembly rest the saddle of the cylinder on a hard surface (e.g. jaw of a vice) so that the end cap will come off easily (make sure it has something soft to land on just in case you need to use it again).

Getting the brass big end off the piston rod is a little tricky. Secret is to make sure you hold the piston rod securely but without damaging it - that is no mole grips unless you are happy to scrap the piston rod - try using a piece of leather or similar wrapped round the piston rod and clamp it in a vice.

If your cylinder assemblies were fitted with the old Mamod gaskets then these will need replacing as they generally disintegrate upon removal - if it is fitted with the later MSS gaskets careful prising off with a blunt edge may be successful.

After fitting it is recommended to use the original Mamod pivot springs until you have the new assembly run in. Also you will find that unless the steam oil has been thinned due to heat that these pistons will be very stiff to move - when I fitted the IP Eng upgrades I flooded the cylinders with lots of light oil (3 in 1 or similar - do not use WD40 as it eats 'O' rings for breakfast) which helped the running in process until the steam oil would flow properly. These 'O' rings need regular lubricating - use of your dead leg lubricator has been covered in the other topic.

Chris Cairns.

[Spule 4]

On the IP modified pistons and glands on my SLK1, while the were a tight press fit on the SL1K cylinders they did not hold in at all on the SL3 cylinders. I wanted to use them as they had the dished backing plates like above, where the SLK1 set were solid, and VERY leaky.

A bit of soft solder and a couple flicks with a torch was all it took.

I am wondering if the MSS cylinders, being single stock Vs. being soldered together may be another option, with the rebuild kits....or just get a set from Roy Wood.

[Crackingjob]

seriously Chris we need a mamod technical book from you
Thanks

[bessytractor]

in answer to the question, yes there is a glue that can hold the piston to the rod, its called silver solder!

Sadly Dream Steam insist on gluing pistons to the piston rods, I have had several come adrift and I now silver solder them as a matter of course to avoid further issues.

[Spule 4]

While you could sliver solder them, the heat and the O rings is going to be an issue. The cylinders should not be getting hot enough to melt most soft solders, so I did this.

Also a bit easier to un-do as needed!