So I bought a pair of locos from someone over the weekend, the premise was that they had cracked gears. No big deal, use locos need a tune up anyway. The GP20 was completely frozen with old oil, so I completely cleaned out every crevice in the trucks and body with alcohol and swabs. I replaced the cracked axle gears, and now they run fine, though the motors make a little bit of a ticking noise. This is coming from the actual motor and not the trucks, as I disconnected the trucks and ran the motor with alligator clips attached, and it’s noisy. I tried cleaning and lubing the commutator as Labelle instructs with 107, this really didn’t do much and left a black streak on the commutator again. Is this the normal behavior?
At higher speeds (about 1/2) it’s more of a quiet buzz. I lubed all the moving parts of the drivetrain with a drop each of 102, and the gearboxes with a dab of 106 grease during the tune up.
Both engines are still DC with the original boards in them. I’m running them on a 34x56 loop of Bachmann EZ-Track, with an MRC Railpower 1350 power pack.
Do I just need to run them more, or what?
Maybe check out the brushes. Just be careful, and not let one of the tiny springs go flying, while taking it apart.
Just an idea.
Mike.
I would look to see if the drive shafts are rubbing on the weight or wires. Not a lot of room in certain areas on these units.
Good point Soo Line. Also I would disconnect the drive shafts from the motor and see if that clicking sound stops. My first thoughts are that maybe since the loco had cracked gears that at some point a universal joint became out of phase and that may be where the noise is comming from.
It’s still making the noise. Is it safe to leave a loco unattended running in a circle for several hours? I could let it run while I’m at work.
Are those from the batch that had cracked gears?
What about getting another motor?
So, what I’ve found so far is:
The motor vibrates when unloaded. A buzzing noise comes from it. But it seems to not vibrate when attached to the drive axles and frame (loaded.) It’s then very hard to tell if it’s the motor or trucks making the noise. Can the motor spindle be removed? The flywheels seem to be machine-pressed on.
The trucks rattle when power is directly applied to the motor and the trucks aren’t touching anything. The wheels spin for awhile and then stop, then start again. Do the wheels disengage when no power is applied? Do I have a chipped gear tooth on one of the non-axle gears? I didn’t see one when I was cleaning the trucks, I’d think such a thing would be obvious if I was examining them one at a time.
There is at least a flange worth of side-to-side slop in the wheels. They are correctly spaced acording to my NMRA gauge. I don’t know if this is the source of the noise, or even important at all. The gears are new, the bronze bearings are new, the wheels are old but were checked for “no-go” and a micrometer, and still match the new wheel width of .110.
you get some buzzing with open frame motors. Is the armature (too) loose in it bearings so it is bouncing? Are the gears square on their shafts? is there slop in the drive train? if so use some washers (Kadee coupler will do in a pinch) to remove excessive side-to-side or back & forth (worm) motion. Also a drive shaft U-joint could be split or worn or not tight on its shaft (the reason the wheels spin stop spin). Are the sockets in the truck frame for the gear axles worn oblong? Can you try running the truck with a better motor?
I looked at you initial post. I have Proto 2000 GP7s & E7s that run very smoothly,no buzz or ticking when running on DC (you are not using pulse DC, right?) Clean the commutator again and the brushes. Do NOT remove the armature out of the motor (magnetic field poles). Clean the slots between the armature pole segments very caerfully using a wooden tooth pick. DO NOT put any oil, grease, etc on the comutator (or brushes). Make sure the curved brush face seats on the comutator. apply only a small amount of oil to the bearings being careful not to get any into the comunator area. It is very possible that the motor bearings maybe worn out allowing the amature to bang around inside instead of smoothly rotating in the bearings. Since these locos are used, how hard & long they were operated, maintenance, etc is not known, it is possible the trucks and motor may be worn out.
I’ve removed Athearn brushes before - you just have to do it slowly so the spring tension isn’t released all at once. Can the brushes be cleaned? Also, Labelle actually recommends using 107 on the commutator because it’s conductive. I did do that and it didn’t seem to help anything, but didn’t add any noise either. The loco isn’t stalling, just has a slight buzz. Removing the board and alligator clipping the wires together did get rid of some odd pulsing that it was doing on some sections of the track.
I am using a Walthers Trainline GP9 as a comparison. It has no noise at all, just the swoosh of the wheels on the tracks and the clicking going over joints.
The GP9 has little to no wear on it as far as I can tell. The GP20 and 30 may have a lot of hours on them. Judging by the wheels, I’d say they do, so motor noise may be an issue.
If worse comes to worse, it’s probably something I can live with. I plan on putting sound decoders in them anyway, which will drown out noise at this level. I hate masking problems though.
If you have power continuously applied to the motor, the wheels should keep spinning.
Yup, Henry is right, so, have you checked the worm gear that connects to the trucks? If a thrust washer is missing, you’ll also have a “ticking” or jerky motion. There should be one on each side of the worm gear.
And, with no weight on the trucks, kind of suspended in air, like you described, the wheels stop and start, even leads me more towards the worm gear, and how it contacts the gears in the truck. There is not much tolerance. It doesn’t take much to disengage the worm gear from the truck gears.
Just one more thing to check, if you haven’t already.
Mike.
Try removing the brushes and spinning the motor shaft by hand. Does it still make the noise? If so, the bearings are dry or worn.
If not, the noise is coming from the commutator, and the plates may be slightly uneven and catching on the brushes ever so slightly. This will cause a buzzing noise and wear the brushes out quickly. Speaking from experience, it’s not an easy problem to fix.
The thrust washers are on there for sure. do they wear out? I was very careful to replace them both when reassembling each truck.
I would have lubed the Armature shaft bearings/bushings while I was doing greasing of the gears. Not very easy to get at on some motors…but they do dry out and will get noisy, also make the motor run warmer. Also check drive-line connections, at the fly-wheels.
Good Luck! [:D]
Frank
hello, I have a GP 30 I just picked up from ebay, it was listed as new. After I’ve had it for a few weeks I finally get time to inspect it. I put it on the rails, only to have it sit there and buzz. I tried to move the flywheels, but the movement is limited as well. After a couple tries, they start moving, and I can see the drive shafts moving. Set it on track, power it up and its moving, only with a clickity click! Check to make sure its railed ok, and it is.
In other replies on your post, I’ve read something about cracked gears. Is this something that is common with Protos, or is it with a few models?
I’d like to keep this loco, but since I just got it a few weeks ago, I have the option to attempt to return it to the seller (I hope), and either have them exchange it or refund my money .
It very likely has cracked gears, a common problem with Life-Like four axle diesels.
See earlier posts for possible solutions.
I’ve had older Life Like GPs with cracked gears so bad that it inhibited rolling by quite a bit, like severe binding. That’s probably the problem.
Also, LL used to put an excessive amount of peanut butter colored grease in the trucks, which is probably rock hard by now. Hard grease in the trucks and truck towers can cause binding also.
I would remove the trucks and clean them by the the methods listed above (also, don’t underestimate the value of placing them in stream of really hot water from the faucet), and replace the axle gears.
If you’re interested in the first part of the thread, in my experience, older LL GPs accumulated oil and schmutz everywhere. If you’re not averse to taking the loco apart, I would solve odd noise issues by simply running the trucks and motor/drive under the hot water faucet. No kidding.
Clean out the obvious goop that you can see, then let the rush of hot water clean out the parts you can’t see. Make sure the tape on the bottom of the motor (top of the frame) is secure or replace it. More than 50% of the time those non-gear related noises went away after a simple hot water flush.
I would generally just blow out the water in the motor hard and reassemble and run the loco right away, but my official advice is to let it dry overnight.