I hope this is a simple question, more than likely not. This is a older problem so please no Ken can break anything answers OK. I no longer run long trains, 25 cars is my max.
I had a bad engine harness in my BLI M1a. I took it apart and then sort of forgot about it. After a few months I reassembled and it took a few me a few times to get it right, well sort of right.
I handle the engine way more than I wanted. Now at slow speeds the engine moves with a jerking motion. Does that sound like the wheels are out of quarter? Only one I have had that I knew the drivers where out of quarter was a BLI Heavy Mike and the wheels where locked up. It went back to BLI for repairs.
After you kind folks give me some idea besides collecting stamps. I will pull the motor again and see if the engine roll freely.
I think this discussion was going on somewhere around here recently. The wheels on our models don’t have to be quartered, other than to look right. They do, however, need to be all the same on each side of the loco. For instance, if you run the loco, then stop it when all the counterweights on the drivers on one side of the loco are at the bottom of their rotation, all of the counterweights on the opposite side of the loco will be, on a properly quartered loco, vertical, either at the front or the rear of all drivers. If any counterweight on either side of the loco is in a different position than the rest on the same side, that driver has slipped on its axle. More than one driver can slip on its axle, and it’s possible to have drivers on both sides of the loco out-of-quarter, too. Most of our model steamers have quite a bit of slop in the drive rods, so a wheel slightly out-of-quarter won’t cause much problem, although if the driver has slipped on its axle, there’s the possibility that it will slip further, eventually causing problems. NWSL offers their Quarterer to fix this problem and it works well. However, some locos can be satisfactorily re-quartered “by eye”.
I can give you an etreme example of an out of quarter’d locomotive (the problem was actually caused by a broken drive gear/axle on an old Bachmann 4-8-4 pancake motored loco).It would get about two rotations of the drivers (if I was lucky that is) before the axle/gear spun or split and cause the locomotive to literally just about hop off of the track, the wheels wouldn’t be anywhere near be in synch(wheel weights were at just about every point of the compass),the side rods would be at angles up to 40+ degrees out of line (they were multi-piece side rods) and everything was bound right up.
If it’s just one wheel, the “twist” should be enough to correct the problem. If this is the case, give it a very short test run to ensure that everything is okay, then apply some Loctite or ca to the wheel/axle interface, to prevent it from slipping out-of-quarter again.
If the wheels are not the problem, check for siderods (on either or both sides) hitting one another, or catching on the driver counterweights - sometimes this can be corrected simply by a slight bending of the appropriate piece, while other times, the rods may have to be disassembled in order to insert spacer washers in the appropriate places. I had one loco on which one piston rod was too long, causing it to hit the front of the inside of the cylinder casting on every forward stroke. [:O] This sounds like it would be an unusual situation, but on many locos, the cylinder casting is able to pivot slightly if its mounting screw is loose - if the rods are longer than necessary to stay in place on the power stroke, they can hit the front of the cylinder on the exhaust stroke.
I’d be very surprised if handling the loco during a repair could knock a driver set out of quarter, and if it did, something was defective to begin with. I think BLI drivers are a darn sight sturdier than old Bachmanns mounted on plastic axles. I am much more suspicious of something along the lines of valve gear interfering with the main rod, a burr on one of the crosshead guides, or even a split axle gear. You can generally spot a quartering issue right away, because the side rods won’t be in a perfectly straight line, and you can see the binding as the drivers revolve. They will strain and deflect, depending on how much play is built into them.
I would turn the loco upsidedown in a foam cradle and run it at very slow speeds and watch closely for any interference when it hitches, and listen for clicking from any of the linkage. Make sure you didn’t over-tighten the axle cover, and that it’s centered and not askew.
Someone had a thread here recently about a similar problem with a P2K Berk.
Again thanks for the quick answer! [8D] I am sure (so that will be the problem) it is not the piston rods. I did not have the drivers out and it ran fine till it lost power pick up from the engine. That is when I found the engine wiring harness was bad. The old M1a does have some time on the old clock. It is my second oldest steam engine.
I have yet to find the time to check out the drive rods and or pull the motor to see if engine is free wheeling.
Thanks for the ideas again and I will up date by Friday.