GWR RAILCAR'S.

GWR railcars were wood framed vehicles, they had a tendancy to catch fire.
Just wondered what caused this fires in the first place?

Can you please explain.:drama:

 

I haven't read anything about them catching fire, but it doesn't surprise me really.
The mixture of a hot exhaust with a fuel leak could always cause a fire to start in the underframes which would quickly spread to the superstructure. Also in a cupboard in the guards compartment was a steam generator, which was basically a flash boiler using diesel fuel, these devices could catch fire if not maintained correctly.
No. 22 still had the steam generator in place until the mid 90's (I think, Railcar22 correct me if I am wrong), but it was removed as beyond repair (which with hind sight was a shame).

 

I haven't heard of this before, hopefully someone can enlighten us. But at the time they were built, the majority of passenger coaches were wooden built and lit by gas and there are few reports of fires in this type of stock (except in the case of crashes). I can't see any reason why rail cars should have been more likely to catch fire.
Just to expand this thread. I believe the streamlined AEC rail cars were the most beautiful diesel units ever built.

 

I've a feeling I read somewhere (GWS Echo?) that a couple of them at least caught fire, with one at least effectively destroyed in the Bristol area - I think the theory was that inadequate cleaning led to a build up of oil and other grot on top of the fuel tank or somewhere similar, and this was then ignited when it got overly hot from the nearby engines. I'll have a look to see if I can find the relevant reference later but my home internet is playing up so may be a while before I can get back to post by which time I suspect Railcar22 may have better info if he's around.

 

A bit of info here, last paragraph.

http://www.greatwestern.org.uk/aec3.htm

 

As one of the guys that works on no.20's at the K&ESR, we found that there was a lot of brake dust and oil/grease that had accumulated an an area of the frame under the train heat boiler. This is area is directly above the final drive/cardan shaft to the bogie, and as such, there would be oil/grease thrown up from these items. All of this, we found gave about a foot of frame a 1" to 2" thick layer of nasty, and if something hot were to drip off the train heat boiler, a fire may start. This may all be wrong, but its what we arrived at over a cup of tea!

 

It is quite possible that some caught fire due to leaks from the supply pipes to the injextors, as these were directly above the exhaust pipe and manifold. There is another possible explanation, as to why 3 of the cars from the 2 twin car units caught fire. LT in the mid 50's were investigating why a pre war RT caught fire. they had a witdrawn STL on test and It was left in gear with the engine running, this overheated the Fluid Fly wheel oil, and the bus after a short while burst into flames. There is a series of pictures of this test in a book I have, but I am on holiday at the moment, so don't have the book to hand

 

Thats the only problem with fluid flywheels. If you leave it in gear with the brakes on, it hots up a bit. There were a few instances on British Railways with diesel shunters and DMU's when they dropped the fusible plugs on the Fluid flywheel or caught fire. Particularly with the 03/04's when all they do is light shunting at low speed, you get oil and grease accumulating all over the fluid flywheel. I remember when the 03 at the K&ESR did a trip to Rolvenden and then came back up the hill with a train, all of the oil that was on the fluid flywheel started to smoke as it got to grips with the climb. From a distance it was hard to make out if it was the 03 or a steam loco!