The main reason for indirect Walschaerts valve gear was due to the fact that early and small steam locomotives did not employ a power reverser. Because the valve rod was lifted up on the expansion link rather than down, the engineer had the assistance of gravity when he was hooking up on the johnson bar as the valve rod was being lowered rather that raised. BTW I really appreciate these in depth, technical videos and hope to see more of them. It is so hard to find good information about operating and maintaining these beautiful machines (the ICS books are a great start). I'm working at my degree in mechanical engineering and have been studying steam design for years. I've been fascinated with these machines ever since I was little and I am actively trying to get involved with steam projects like these. There is still so much left for me to learn and people like you are helping to make sure that I can be able to accomplish my dream in life, delayed gratification, you know! ;) So from one steam lover to another, keep on keeping on!
I too could not find much good technical information about steam locomotives when I started this project so I figure that now that I have gained some knowledge, I would share it. There are many more topics that will be covered as we maintain and operate the locomotive.
Thank you for this video. I learned a lot of stuff for a project I'm working on. Will definitely go through other videos and see what other gems I can find. I loved the part about adjusting rod lengths and only pulling forward to get all marks right
I believe the difference in the direct and indirect valve gear, is with direct valve gear, the radius rod goes in the lower position for forward, this was because of force of a running steam locomotive was powerful, and used gravity to help the radius rod move while adjusting the cut off while on the road. Now I may have these mixed up. With Indirect using gravity to help adjust cutoff again I may be wrong, but that is what I read a while back. I am going to have to go through my research. Take Care, and awesome work!! I hope to learn more, as I too, would love to one day work on mechanical masterpieces such as these.
It probably didn't have as much to do with hooking up the valve gear as it did with placement of the tumbling shaft and its arms. The typical way was to have the arms on the right side be in an "L" shame so pushing the top forward (putting the Johnson bar in forward) would lower the valve gear (into forward on the bottom part of the link). Some locos have the right side arms as a backwards "L" so pushing the top forward will raise the lower arm (into forward on the top part of the link). With power reverse, this could be reversed but with a Johnson bar it was typical that reverse would be in the top part of the link with the backwards "L" tumbling shaft arm set up. Some 3' gauge 4-6-0's that used Stephenson valve gear had the backwards "L" shape for the tumbling shaft arms but their Johnson bars were set up differently - the reach rod connection was below the pivot on the Johnson bar so pushing the Johnson bar forward would pull back on the reach rod and lower the links into forward.
Loved that video and the technical description, so much better to see it done for real than just in a book. I suppose the first stage in setting up would also be to check and fix any wear in the valve rod linkages, axle blocks, bearings and horn guides, crank pins etc etc?
Did not move at all, lol, nice you look back at the video and you can see it didn’t move, nice love this it’s beautiful, thanks nice good job, thanks BigAl California.
@@YoungstownSteelHeritage not 100% true, but about 99.9% true :). There are a very few which have 2 cylinders, and are compound, therefore either have simpling valve to supply steam, or some other arrangement. Ones that come to mind would have been the Doble's, and I'd think, A&P Traction Engine conversions (of which, I think there are 2 in the UK).
It definitely moved out some when you moved the bar the first time. It did not appear to move in when you went the other way so likely some slack in the linkage. So in the end how did you adjust it? I didn't see threads on the piston rods to lengthen them.
WOO HOO - utterly fascinating !!! Thank you ! Curious about wheel slip that first run . . . on purpose ? y'all use sand ? And yes, sounded much better second run.
What's interesting about this engine after listening to it a bit, (and the 2021 dirt train video) is that she sounds happier in reverse than forward, which would almost seem to indicate mechanical wear on something in the driving gear because if it's going to be off, it should be off equally. Are the bearing pedestals square in their bushings? Trying to think what parts could wear from more forward operation than reverse.
Was thinking the same thing. That's quite a steep grade in an autumn forest with bits of ground up leaves coating the rails. Building a working automatic sander could be a nice project and would also be a useful addition to the diesel locomotive for use in icy winter conditions.
Hey there! I'm also in the process of Helping a Mechanic do it's first Timing on a Walschaert Valve Gear locomotive. And that book would be super helpful! The problem is.. all the ones i find online are missing the pages were those procedures are explained! Do you maybe have a digital copy you can share? Or a link to buy the proper book? Thank you!
Not sure why you didn't just use a set of feeler gauges and a timing light, that's what I use when checking valve lash and timing on the old chevy... Lol ! Nice translation from text to audio and visual !
It is difficult because after making an adjustment it requires another fireup to see if it had any effect, then it takes a few days to do the teardown and machine work to make an adjustment, and then another fireup to test.
What happens when the valve timing is not right on your car? That’s right, it runs very poorly, or not at all because those out of time valves got wiped out by the pistons.
awwww BS. set the number 1 driver at TDC, and git yer timing light out. then loosen up the johnson bar and rotate it to get right at 5 degrees BTDC. tighten er up and call it good.