Manning Wardles "YEO" and "EXE" new-build

Thanks for the link Chris. It is reassuring to see that provision is being made for additional motive power after Exe and Yeo. I'm sure that updates will be more frequent as we move out of lock down......which will be good.

 

When Lyn was built, the valves were changed to piston type to increase efficiency/power. It would appear that a similar modification is not planned for the Manning Wardles, can anyone comment on why this might be?
I seem to recall a website or forum posting detailing quite a number of operational issues with Lyd, such as ashpan access and oiling of motion/axleboxes. Have these items been looked into and suitable modifications made to the design for the replica?
Will the M-W locos have roller bearings like Lyn?
Thanks in advance for any info

 

There is another Exe and Yeo thread on P3 of this section.....perhaps the mods might combine them now?

 

Make life easy for them - “report” this thread and make sure you include the link to the other thread to save looking. Just adding a post here won’t necessarily be seen.

Tom

 

Thanks for such a prompt response Pete.

 

I have been informed this evening that the new build Manning Wardle 'EXE' and 'YEO' locomotives will NOT have roller bearings fitted. Both new L&BR Manning Wardle engines in this respect will be identical to the arrangement fitted on the Ffestiniog Railway's 'LYD'.

 

Thanks for the update, do you know if there is a particular reason why the M-Ws are not being updated?

 

Makes sense to use the drawings/castings that already exist for Lyd, not only can you use them pretty much "out the box" but the design has been proven to work bar a few necessary changes. Also helps to reduce costs and the overall timescale. It would be nice to incorporate some of the modern features such as roller bearings but I can't see them being all that necessary tbh.

 

I imagine someone has taken the view that it isn't cost effective or necessary. The valve gear on Lyd has been very reliable and suffered little wear over 10 years. Would an expensive re-design be fixing a problem that doesn't exist? The valve gear has some very tight clearances would it just introduce new problems trying to fit roller bearings into it?

There are some more pressing issues such as the superheaters and ashpan that are being attended to at the current overhaul. I expect that the new engines will continue to benefit from the experience of running Lyd.

Tim

 

What problem does fitting roller bearings solve?

People sometimes talk about such features as an unalloyed benefit - but plain bearings work, and changing them requires substantial redesign. So there has to be a significant benefit to doing so, even ignoring the questions of to what extent you are building a replica as opposed to a looky-likey.

Tom

 

Indeed it's always a compromise. It is much easier to design a loco with roller bearings in mind than it is to retrofit them.

Most of the FR locos have standard sized Oilite bushes and hardened pins in the valve gear. When it comes to overhaul you just push the old bush out and press a new one in. They are grease lubricated too. A good solution to the same kind of problem.

Tim

 

I'm not really bothered about the roller bearings side of things, as James says, it's solving a problem that doesn't really need to be solved and as Tim says, could create more problems with the valve gear and modifications to the rest of the loco. It was the valves that I was primarily thinking of regarding updates (and yes I know it is a massive amount of work to redesign).

I am more curious as to why Lyn was built as an updated 'looky-likey' but the M-W's are being built much more to the original design. No criticism of the project is intended at all, just genuinely curious as to why one loco was built with updates and the others won't be.

 

The cylinders on Lyd are updated with balanced slide valves. They work well now the lubrication issues have been fixed. I believe piston valves were discounted as they would change the appearance of the engine too much. Lyn has huge valve chests which makes it easier to hide these things.

It's worth noting that Lyd is quite different to the original design in the details. A lot of thought went into things like materials. Some bits have worked out better than others. Where they haven't such as the ashpan and superheaters, they are being changed at the current overhaul. Having a working prototype will no doubt be of great benefit to this project.

Tim

 

I believe the replica Lyn has greater boiler pressure than the original and high degree superheat with the aim of improving efficiency and performance. Experience suggests that there would be problems lubricating slide valves so it was probably essential to use piston valves.

 

It may be that, in the future, G***a Th*****g and her pals will come after us for the amount of oil that we splash around. (When they have finished with coal.) Anything that reduces that has to be a good thing, financially as well as in PR terms.
Pat

 

I think she might be a bit busy trying to influence geopolitics for the benefit of all humanity. The minutiae of lubrication on a 1 mile long Devon tourist attraction is probably quite far down her agenda.

Tim

 

Hopefully it will be longer than 1 mile before the new engines are available.