Mk3 Creaky Gangways

[hexagon789]

Thanks. They don't seem to creak like Mk3s yet sometimes you get a bit of an audible jolt as the carriage starts to move away from a stand. They don't always seem to do this though.

Possibly the couplings? HST Mk3 trailers have Alliance couplers (effectively fixed-head buckeyes) which do have some slack in them, Mk4s are tightlock which eliminate coupler slack by design.

 

[superjohn]

The creaking gangways and, even more so, hissing and groaning of the air suspension is the trademark of the Mk3. The sound when slowly lurching over points or when emptying a full load of passengers is very distinctive.

Same goes for grinding brakes on Mk2 stock or the ‘tink’ of Mk4s going over points or joints.

I like the eerie quietness you get when setting off in a class 317 trailer. The gentlest of hisses as the brakes release and then it starts moving almost silently. Something changed with the otherwise similar class 319/321 design, their brakes have a much more pronounced whoosh of air when released.

 

[hexagon789]

I like the eerie quietness you get when setting off in a class 317 trailer. The gentlest of hisses as the brakes release and then it starts moving almost silently. Something changed with the otherwise similar class 319/321 design, their brakes have a much more pronounced whoosh of air when released.

It's interesting you should mention that because I would say the same about 318s against 320s, yet both use the Westcode 3-step brake system

And both have squeaky gangways! (Though only really noisy at speed.)

 

[PG]

Thank you @coppercapped for the explanation and insight.

The groans come from the various linkages (if not kept lubricated) and rubbing surfaces. All Pullman gangways exhibit this characteristic.

I'm curious if the linkages were ever lubricated as I've travelled on HST's most of their service life complete with the creaking gangways?

 

[xotGD]

Same goes for grinding brakes on Mk2 stock

I find the sound very soothing. Unlike the vestibule creaking!

 

[dubscottie]

The choice of coupler also dictates gangway type. Buckeyes cannot take compression forces so require a Pullman gangway or rubbing plate. The MK4 were to have buffers & Mk3 style gangways (the coaches still have the holes for fitting buffers) but BR changed to sealed gangways which dictated the use of tightlocks.

Buckeyes are noisy things anyway!