(28 Apr 2016, 5:20 pm)South Tyne Lad wrote Heaton does have a Wheel Lathe as Neville Hill 158s and Newton Heath 142s and 150s have visited in the past for that very reason.
Though it isn't daily, If Neville Hill is busy on other units that's when they get sent up here.
Yes there is a Knaresbourgh to Heaton ECS after a peak time Leeds - Knaresbourgh, It is also indeed booked for 2x 142s though no 156 should ever appear there, 1x 142/1x 150 can sometimes happen at the most, The 1x 142 being a Heaton unit worked up the night before to work the day on Heaton's Diagrams in Yorkshire and the 1x 150 visiting Heaton for maintenance when Neville Hill is too busy.
If its 2x 142s then both will have ran up the night before and done what ive mentioned above.
Heaton Units are Diagrammed to appear in Lancashire daily, The Cumbrian Coast has a handful of diagrams utilising a Heaton 156 and on 1 or 2 a 153 attached too.
These units work from Heaton on either the Tyne Valley extension to Whitehaven or through a Tyne Valley service which terminates at the through WCML platforms around 1600-1900 time and works the next Cumbrian Coast service out.
Some North West units have ended up here though it Heaton 156s in the North West happens way more likely than a North West unit up here.
HT does have 7 former FNW 142s allocated which are frequently seen in the NE. 142 023/7/9/64/67/68 and 70. 063 seems to be a regular up here now so suspect this is now allocated to Heaton.