Wednesday, 5 July 2017

40 years of dirt!

Preservation, it what you will! One thing it is definitely not is boring! There is always something that jumps out and piques interest in the history of the artifacts we deal with, that is slightly beyond the pale. The overhaul of Class 24, 5081 is definitely one of those times. It has been mentioned in previous blogs that the last major works overhaul of the locomotive was in April 1975 and it is likely that that is when the bogies were last given major attention. The past weekend saw myself and Mark E get up close and personal with the traction motors which allowed us to further peel back the historical dirt - with the aid of a very powerful steam/pressure washer - identifying makers marks on the motor casings as well as damage and repairs.

It was hoped that in this coming week (in fact it happened on Tuesday just gone) the bogie could be taken over the pit outside the shed for the Traction Motors themselves to be removed ready for overhauling. That meant that the weekend would be spent removing, cleaning and assessing the motor casings and gearing. Nuts and bolts had been loosened in preparation, and we now went about the tricky process of removing the two casings.

Bogie #1 - The traction motor gear casings are top left and bottom right between the wheel and traction motor.
Casing #1. We managed to remove both top and bottom sections. Casing #2 was removed fully when over pit.
Casing one was removed with relative ease as there was nothing obstructing the awkward removal - particularly of the bottom half. As it is made of aluminium no needle gunning had taken place and the casing was encrusted in congealed dirt and grime. However, the main worry was what would present itself when the bottom section was removed!
The top half no.1 casing. In pretty good condition....externally!

The traction motor gearing. In very good condition for nearly 40 years old! Certainly, very well lubricated!
On removing the top half, it revealed the motor gearing which appeared to be in very good condition. None of the teeth seemed to be worn and both gear wheels were very clean and lubricated. The only problem identified was some damage to a very small seal which could have caused some damage to the motor and dirt ingress.
Looks like a small piece of rope, however, it is a damaged seal. Luckily, it hadn't seemed to have caused much of an issue.
Then it was time to remove the bottom half. We were both expecting it to crash to the shed floor, a piece of wood readied to 'catch' it. However, the lubricating fluid used on the gearing, called Motak, had gravitated to the bottom and was creating a vacuum preventing it from falling away. With a bit of pressure the casing came away....but so did the Motak!! Cue mad dash for suitable absorbent cloth!

Looks like Marmite, but you definitely wouldn't want this on your toast!!! Or on your hands!
This stuff is incredibly toxic and it was going everywhere! We managed to contain it as we didn't want it going everywhere. Despite being incredibly dangerous, it is a very effective lubricant at high temperatures, and the condition of the gearing demonstrates its effectiveness. After sorting casing no.1, we went to the other end of the bogie to try and remove casing no. 2. However, we abandoned this job as, to remove the bottom part of the casing, we would need to take it off over the pit. The frame for the hand brake mechanism stopped us from sliding it out as we had done with casing no.1. We had a quick check of the gears and found them to be in very good condition as well.

Traction Motor no.2 gearing. Also in good nick, but the top casing had to go back on and await time over the pit.

The 'fly' in our ointment! Cold, hard, riveted steel!
It was then time to get out the pressure washer and give the casing for Traction Motor 1 a good clean! The dirt was probably about 3mm thick and the actual external metal work had not seen the light of day for decades! Mark started off and then I carried on whilst Mark removed other parts ready for the Traction Motor lift.
Mark starts the cleaning of the casing. It was to take a lot longer than we thought! 40 years of dirt doesn't come off easily!

As we cleaned, the makers mark saw the light of day for the first time in 4 decades! Light Alloys Ltd, London.
As the dirt was removed, several things were revealed. Most notably was the makers mark - Light Alloys Ltd, London. We did a quick internet check and this company had long since dissolved. We were quite surprised that the aluminium had survived the onslaught of filth and outlived the makers. The casing was in quite a decent state, although a couple of repair marks were found. One of the casings had come loose many years before and had to be repaired. Mark wasn't sure he remembered which casing it was, but, evidence seemed to point to this one.  

You can see that the muck had dissolved a lot of the original top coat of paint and the red oxide primer is clearly visible.
As I continued to obliterate the 4 decades of dirt of the casing, Mark returned to the bogie and removed several more bits that needed cleaning. Not only were the traction motors due to be lifted out but the remainder of the springs were to be lifted out as well. This meant that a variety of castings were removed. The dirt kept coming! By the close of play the jet washer certainly knew it had been in a fight and the skirting outside the shed doors had turned a fetching shade of brown!

Mark brings out the internal gear runners. You can see just how much filth had accumulated on these...nearly a centimetre thick!
The removed brake mechanism and main suspension rigging had been cleaned, polished and, in places, had been treated with red oxide primer ready for refitting when the time comes.

Elsewhere with 5081, Mark S and Andy M disappeared into the engine room to look at the oil priming pump which had started to allow too much air into the oil mix causing a few minor issues. Although the loco had not run since November 2016 (which could have partially explained the problem) further investigation  identified that a seal needed replacing.

The offending Oil Priming pump.
Mark S quickly fashioned a new seal and fitted it to the pump, it was tested in situ and seemed to run without problem. The acid test will be when the engine is running...another job for the coming week.
Andy getting ready to reattach the pipework. To the right is one of the Traction Motor blowers.
Dave M and Ian R were also up at the depot continuing the overhaul of 47105. The furniture is slowly being replaced into the cabs and the refurbished cab doors are back on their hinges. The foot boards were also cleaned. These will go beneath the cab doors to prevent damage to the paintwork.
Foot boards for under the cab doors on 47105.
Neil C also popped into the shed in order to repair and re-install one of our battery chargers. Originally, this one was stored over by our gantry crane and was used by the Cotswold Mainline Diesel Group to charge the batteries on D5343 and 45149. The cab that it was stored in had started to rot and become unstable so it was agreed to place the charger in the shed, in an accessible place to allow the charging of the two CMDG locos on the apron of the shed rather than in a potentially dangerous place. 
The nearly refurbished, reinstalled battery charger.
And, on the Sunday, the DMU gang were back at the Class 121 'bubble car' -

"Bubble Car Update!!!!!! Another busy day for the DMU crews with the Bubble Car being the focus of attention. The exhaust pipes have been connected up and the Bubble Car's distinctive look is once again back. Kevin Haines, unsung hero, has put in some more desk paneling on the south cab. Kevin has also finished off the wooden trim around the cab windows. And a mighty fine job it looks. Well done Kevin.

The crews have finished off the last few jobs that did not get finished off last Sunday. Fuel lines were checked over, coolant added, hoses finished off. The teams have been working on the interior trim making sure it is ready for when we can start putting the Cotswold side paneling back on. It is hoped, with good weather next Sunday, that the Bubble Car will once again venture outside over the pit. It is hoped that both refurbished engines will be started and run up to allow for installation checks and to check the modifications that have been carried out.
So watch this space........"

The pipes back on! (Courtesy of CDRG)
The driving desk, more bits and bobs in situ. (Courtesy of the CDRG)
Trim! (Courtesy of the CDRG)
 All this work on the 'Bubble' bodes well for the Gala at the end of the month! It will be in the diesel shed, along with 47105 and 5081, to demonstrate the level of work that goes into keeping these engines running.