Class 31s - the good & bad

[alexl92]

I often hear people being quite critical about Class 31s diesels - the most common criticism is ‘Couldn’t pull the skin off a rice pudding’. But they have been one of the longest-lived classes on the network, surviving with Network Rail until just a few years ago. Are they really as terrible as everyone makes out? Surely they must have been ok to be kept on so long?

 

[Shaw S Hunter]

Compared to the Bo-Bo Type 2s the 31s were getting on for 50% heavier but with only 18% extra power. That inevitably meant their performance compared poorly. However the EE 12SVT engine they were eventually fitted with was a de-rated version of that fitted to the even longer lived 37s, hardly surprising that they lasted well with such a de-stressed rugged engine.

 

[NorthWestRover]

They looked cool too.

 

[gazthomas]

They were pants, if reliable. Hey, let's add ETH to an already under powered loco. Diamond

 

[61653 HTAFC]

They looked cool too.

Really? Of all the several nicknames they were given by enthusiasts over the years, Gargoyles* (or simply 'goyles) was the most appropriate.

*=technically, "Grotesques" would've been more accurate, as they didn't have water spouts designed into their faces!

 

[Kneedown]

We had to stop putting them on engineering trains that involved working in tunnels due to the excessive fumes they put out.

 

[DidcotDickie]

They were (usually) slow, though it depended on what duty they were on. My first run behind a Brush 2 was around 1960 from Upminster to Thorpe Bay on the LT&S where they were drafted in to replace the increasingly knackered steam locos. I seem to recall that performance on the 10 coach ex-LNER/BR non-corridor stock was quite sprightly compared to steam.

In the 1970s I occasionally travelled from Loughborough to Cambridge which was normally DMU. Some of the later runs comprised a 31 and 6 mark 1s from Leicester to Cambridge and vv and they were fine on that. Infinitely better than the purgatory of a Cravens class 105 from Peterborough. I also did a few runs from Moorgate over the widened lines to Welwyn GC around the same time (BR mark 1 non-corridor stock) and they were fine on that too.

Where they were less well suited was on class 1 express services which were normally diagrammed for a class 47 or similar. The Harwich Boat Trains from Liverpool St in the 70s usually got a class 37 which was noisy but got you there. Some of the Prinz Lines boat trains for the Harwich - Hamburg ferry ended up with a 31 on 12 mark 1s which meant that you were down to walking pace by the top of Brentwood Bank

 

[randyrippley]

presumably they were OK on their East Anglian / East coast original homeland, where there are no real hills..........once they moved to the Western as Hymek replacements the lack of power became obvious.

 

[DarloRich]

I assume they survived long on test trains as they were almost go anywhere and were available!

 

[TheEdge]

presumably they were OK on their East Anglian / East coast original homeland, where there are no real hills..........once they moved to the Western as Hymek replacements the lack of power became obvious.

Apart from most of the GEML north of Ipswich. And the East Suffolk Line. And the notoriously steep and sustained Brentwood Bank. Brentwood Bank is so flat I've known GA 90s to sometimes start to tail off...

 

[Pigeon]

They were pants, if reliable. Hey, let's add ETH to an already under powered loco. Diamond

Not just any ETH, but massive ETH, with an index of 66, which was about a third of the total power output. Chug chug trundle trundle.

I've also read that the ETH conversion was something of a crude bodge, and at least in some implementations meant that that power wasn't available for traction even with the ETH off. Can't remember where though, and trying to re-excavate the reference reveals only the falsity of the claims that the internet "puts all human knowledge within instant reach".

 

[randyrippley]

Apart from most of the GEML north of Ipswich. And the East Suffolk Line. And the notoriously steep and sustained Brentwood Bank. Brentwood Bank is so flat I've known GA 90s to sometimes start to tail off...

But they're not real hills compared with Devon, Cornwall, Wales...........
you East Anglians don't know what a hill is..............

 

[randyrippley]

Not just any ETH, but massive ETH, with an index of 66, which was about a third of the total power output. Chug chug trundle trundle.

I've also read that the ETH conversion was something of a crude bodge, and at least in some implementations meant that that power wasn't available for traction even with the ETH off. Can't remember where though, and trying to re-excavate the reference reveals only the falsity of the claims that the internet "puts all human knowledge within instant reach".

that comes from the Wikipedia entry for the class 31, and I don't think there's a proper source for the comment

 

[TheEdge]

But they're not real hills compared with Devon, Cornwall, Wales...........
you East Anglians don't know what a hill is..............

I'm a part Welshman, who grew up in Marches living in Anglia. I know a hill when I see it

 

[dk1]

31s where awful things on portion workings to/from Yarmouth especially on a stopping load 11. Getting up the bank to/from Lingwood was particularly painful. All wind & piss was how I referred to them as a child.

 

[Bunting14]

I understand that it was a choice between them and the class 25s for withdrawal in the 80s. What were the deciding factors?

 

[Pigeon]

that comes from the Wikipedia entry for the class 31, and I don't think there's a proper source for the comment

No, it doesn't. The reason there isn't a proper source is that I can't remember where it did come from.

 

[dk1]

But they're not real hills compared with Devon, Cornwall, Wales...........
you East Anglians don't know what a hill is..............

Chris Evans was made to look very very silly when he made a similar comment reguarding Norwich which he insisted was flat

 

[Midnight Sun]

Chris Evans was made to look very very silly when he made a similar comment reguarding Norwich which he insisted was flat

He confused with the fens which are flat for miles.

 

[dk1]

He confused with the fens which are flat for miles.

Very poor geographical knowledge for national radio DJ. He was inundated on social media & via the telephonic system to the error of his comment.

 

[randyrippley]

I understand that it was a choice between them and the class 25s for withdrawal in the 80s. What were the deciding factors?

Sulzer reliability and lack of spares - Vickers had shut the production line at Barrow, and European parts were incompatible.

 

[306024]

My old boss refers to the Ipswich - Peterborough line as going over the Alps. A touch or irony perhaps but while East Anglia may be relatively flat, the railways were built on the cheap, as the land lies in many cases, so gradients are steeper than you would think. Only read this evening that Stephenson reckoned a 1 in 300 gradient would need double the pulling power back in the day.

So class 31s, useful workhorses if you didn't want to get anywhere quickly. Recall a pair of toffee apples (31/0s) spending a few days on the Norwich's once during a motive power shortage at Stratford. Eventually a pair were found that when multipled up both actually went in the same direction.

 

[D5645]

No, it doesn't. The reason there isn't a proper source is that I can't remember where it did come from.

The entry in Wikipedia is rubbish.

A 31/4 produces the same output as a 31/1 when the ETH is switched off. The only difference between the two is a 31/4 has a modifed Woodward governor and idles at higher rpm.

I suspect that is where the nonsense comment on Wikipedia originated from.

 

[randyrippley]

Chris Evans was made to look very very silly when he made a similar comment reguarding Norwich which he insisted was flat

40 metres elevation sounds pretty flat to me

 

[D5645]

presumably they were OK on their East Anglian / East coast original homeland, where there are no real hills..........once they moved to the Western as Hymek replacements the lack of power became obvious.

Trying to replace Hymeks with 31's was very optimistic. I think there was little other choice as there were no spare Type 3's available.

31's also replaced Class 22's on the WR which they easily outperformed.

 

[Railperf]

Apart from most of the GEML north of Ipswich. And the East Suffolk Line. And the notoriously steep and sustained Brentwood Bank. Brentwood Bank is so flat I've known GA 90s to sometimes start to tail off...

Most of my runs up Brentwood bank see the Class 90 driver coasting to dissipate allowed for recovery time of up to 2 minutes - to avoid passing Shenfield early - plus there is a 75mph limit through the station - which means the train has to reduce speed from the 90mph limit. Sometimes a late running Southend stopper ahead means drivers might see caution signals going up the bank too. And i've lost count of the amount of times there have been TSR's of 50 and 60mph over the older paintwork due to its bad condition.

 

[dk1]

40 metres elevation sounds pretty flat to me

Oh Jesus help me. You been to Naaarich??

 

[randyrippley]

Oh Jesus help me. You been to Naaarich??

somebody had to and I got the short straw

 

[306024]

Most of my runs up Brentwood bank see the Class 90 driver coasting to dissipate allowed for recovery time of up to 2 minutes - to avoid passing Shenfield early - plus there is a 75mph limit through the station - which means the train has to reduce speed from the 90mph limit. Sometimes a late running Southend stopper ahead means drivers might see caution signals going up the bank too. And i've lost count of the amount of times there have been TSR's of 50 and 60mph over the older paintwork due to its bad condition.

Just [1] minute approaching Shenfield these days, and both Gidea Park Jn and nearly the whole layout at Shenfield have been renewed recently so no TSRs. In particular the Southends get a faster run into pfm 4 at Shenfield so the xx.55 from Liv St is more likely to clear ahead of the xx.00 Norwich.

If on time through Gidea Park many drivers shut off power up Brentwood bank at the right spot to get through Shenfield at line speed without touching the brake. Not advisable with a 31.

 

[Railperf]

Just [1] minute approaching Shenfield these days, and both Gidea Park Jn and nearly the whole layout at Shenfield have been renewed recently so no TSRs. In particular the Southends get a faster run into pfm 4 at Shenfield so the xx.55 from Liv St is more likely to clear ahead of the xx.00 Norwich.

If on time through Gidea Park many drivers shut off power up Brentwood bank at the right spot to get through Shenfield at line speed without touching the brake. Not advisable with a 31.

Yes, the 31 would probably be going backwards halfway up the bank LOL.