Weekend Rails

what we do for our kids

Of clutches and suches

28th October 2012

An astute reader, referring to my expectation to have "Tom" back running by the end of this weekend, questioned whether that was a wise plan given that this weekend is the last of the month. For any new readers we find things "happen" on that weekend and all too often to our detriment. Aforesaid astute reader was probably right.

One good bit of news that came through during the week is that the transmission for D2128 has been sorted. You may remember a poem that goes on about "for the want of a nail, a horse-shoe was lost" and so on. Personally I always regard it as a apocryphal tale of when a company is run by bean counters, but anyway, the problem was traced to a newly manufactured joint in the valve block that was missing an 'ole. No 'ole, no oil flow and no second gear. The transmission now tests out OK and we will be scheduling a transmission change at Scunthorpe before too long.

What with the house move, and a few matters of gainful employment getting in the way, I did not get back to Rowsley to investigate "Charlie" as I had planned, and it was fortunate that it did not cause Peak Rail too much inconvenience. With Andrew away on Saturday however, I headed along to Rowsley with the intention of sorting out "Charlie" and getting back on to Tom's wiring.

But it is, after all, the last weekend of the month.

I spent a couple of hours on "Charlie" trying to figure out what was amiss. The loco was last seriously overhauled in 1997 prior to my putting it out on hire in Grimsby. Subsequently we had an engine failure and had to change it over a long weekend, but that too was last century. Sadly, most industrial locos, and especially chain drive ones, develop a patina (as the antique experts might say) or in our case, a sticky mixture of grungy dirt. Moving around underneath the loco, I found that the cam that operates the clutch limit switch was happily slopping around the shaft but refused to move off the end, whereupon it jammed. It was thus only a few degrees out from where it should be if the clutch cylinder and arm were correct and the clutch was disengaged, so I removed these two items, set them up and refitted them. But when I started the loco, firstly it tried to move again, and secondly it refused to engage clutch or change direction. Back underneath once more I peered up through the (missing) inspection cover on the bottom of the bell housing and concluded that the clutch was either partially or wholly engaged. Quite how it had got to this position when the clutch cylinder and arm had quite clearly been in the 'out' position (and the arm was tight on its splines) was not clear, and I decided to leave it for a joint attack with Andrew.

So instead I moved over to "Tom", although it was now getting on in the afternoon and a cold wind was counteracting my enthusiasm. A week or three ago I had been sent a copy of the basic wiring for the alternator which confirmed, as I suspected, that both ends of the field needed connecting, rather than being internal, and before the engine went back I had swung the alternator clear of the block and confirmed which terminal was which, and belled them through to the engine connecting box. Today it was time to sort out the other end. My original wiring diagram had been a "generic" Thomas Hill one - it suits "Charlie" "Jack" and "James" too but with variations on each. So I have it on CAD with amendments for various locos. Thus far I had not checked out how the voltage reg connected in the side of the cabinet, but it didn't take too long to work out what went where, which went through the auxiliary contacts of the battery master switch and allocate a spare wire of the multi-core to feed the end of the field I had previously missed out.

Sunday, and Andrew reappeared from Norfolk as I finished resetting the clocks. We threw some bits in the van and headed along to Rowsley. Today Andrew opted to head underneath "Charlie" and I aided from above. He confirmed that the clutch was indeed engaged (how it got like that is still a mystery) and we repositioned clutch cylinder and arm again having manually pulled it to disengage. We were about that far when Andrew had a call from Richard Ward, whom we got to know when we had 14 901 at Butterley and Andrew runs into professionally from time to time. In this case, Andrew had acquired some miscellaneous engine parts that suited a 47 and he was donating them to Richard, who is one of those involved in maintaining the first of the class. We broke off for a while to pass them over and exchange news and gossip.

After he had departed, we started "Charlie" up and tried to test the pneumatics, but the clutch cylinder simply could not pull the clutch over centre. In part this was because the cylinder has a limited stroke and an adjuster screw to enable you to compensate and prevent it bottoming its piston, but in our case, a significant part of the movement was lost by the amount of wear that has developed in the clutch cross-shaft as it passes through the bell housing. Several further attempts at playing with where the arm is on the cross-shaft and the adjustment on the cylinder piston rod eventually provided us with a combination that worked, but the clutch limit switch is way out of position and the whole clutch assembly is giving us concerns. In the short term, a longer stroke cylinder, such as the ones I bought from the Durley auction would be advantageous, but requires a new bracket to suit.

We moved over to "Tom". I set to work drilling a fresh hole in the electrical box on the engine to bring the multi-core through, then connected up the control and alternator wiring as per my "as built" CAD drawing updated last night. Meanwhile Andrew squatted down in the bowels and reconnected the prop-shaft bolts, then disappeared inside the shed to reassemble the clutch cylinder with new seals. Rain was now coming down steadily, though not heavily, and as I was working with head and shoulders inside the casings but nether regions outside, I began to be aware that my bum was getting cold and damp. (And my knees didn't appreciate me being on the casing runners and supports, either). By the time we had both finished we decided it was time to call it a day, save for a quick trip to the "stores" to dig out a cylinder. So "Tom" isn't quite ready to resume operational testing, but maybe better to do it on the first weekend of the month, for which already Andrew is planning an intensive programme. Yippee.

This site runs on a system that employs Cookies to establish a link between your web browser and our site. This link is required to deliver to you the page you requested, let you see any photos or videos or to use the contact form. The Cookies that allow this to happen are automatically downloaded to your device (pc, mobile, laptop etc) when you click onto our site. If you set your web browser not to accept Cookies then its probable you will be unable to use Weekend Rails properly. Click to Accept (or the message stays visible). To find out more about the cookies we use and how to delete them, see our Privacy Policy.

I accept cookies from this site