Unsilenced 710s

233:

https://www.youtube.com/watch?v=x6XQB_tSZxk

66542 from the UK:

https://www.youtube.com/watch?v=9gjV7WpoyLs

Phenomenally Phrank

233's certainly betraying her GM heritage there!!:D

steamengine

Karsini - 233 running without a silencer then ??? Sounds like a GM now ok
Thanks

dermo88

Thats more like it.....thats what 3,200 horses should sound like.

If I recall correctly, the silencer isolation was a test as 233 was regularly suffering from engine shutdowns due to excessive pressure in the exhaust system. The bypass greatly improved its reliability, so much so that IE were planning to roll it out across the entire 201 class bar the Enterprise locos. However EMD warned IE that this would void their warranties so the silencer was reconnected when 233 was returned for overhaul and repainted in Enterprise livery.

I only caught 233 in this configuration once, which was in Killarney on a Mark 3 push-pull train around 2006.

steamengine

Karsini wrote: »

If I recall correctly, the silencer isolation was a test as 233 was regularly suffering from engine shutdowns due to excessive pressure in the exhaust system. The bypass greatly improved its reliability, so much so that IE were planning to roll it out across the entire 201 class bar the Enterprise locos. However EMD warned IE that this would void their warranties so the silencer was reconnected when 233 was returned for overhaul and repainted in Enterprise livery.

I only caught 233 in this configuration once, which was in Killarney on a Mark 3 push-pull train around 2006.

The exhaust would still have to feed into the gas turbine side of the turbo-charger, so was it a case of removing any baffles from inside each exhaust section rather than a separate by-pass ??? I am still curious as to why the 201's are a lot quieter than the 071's as essentially the layouts of both exhaust systems are the same and they are both turbo-charged. I've put up the two wiki photos to show the physical similarity of both engines. I suppose the question is does the later 710 engine have a more muffled exhaust than the 645 engine or is there another reason ???

class 201
class 071

This photo should clear it up for you. Rather than the exhaust outlet entering the silencer from above, the outlet was simply opened into the air like with the earlier GMs.



Here's a view of the top of a model 201, showing how the connection is normally made. I should have a better photo at home but these are the best I can see at the moment.

steamengine

Karsini wrote: »

This photo should clear it up for you. Rather than the exhaust outlet entering the silencer from above, the outlet was simply opened into the air like with the earlier GMs.

Here's a view of the top of a model 201, showing how the connection is normally made. I should have a better photo at home but these are the best I can see at the moment.

Thanks for the photos, it's in a recess on the cab roof then - makes more sense ok. Just looked at the photo I took of the Enterprise in Skerries and can see it there too.