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I have Weaver A-5.

It makes gear noise going forward, but not backward.

Took it apart, thoroughly added grease by removing the plate that covers the bottom of the gear box (4 tiny screws.) Lubricated everything that I could access from inside.

No improvement noise wise. Grease pushing out front of gear box. Suspect front bearing missing.

It appears that further disassembly of gear box requires dropping the geared axle and gearbox out of the frame to open gear box.

That is beyond my pay grade.

I will have to live with the noise!

@ctr posted:

I have Weaver A-5.

It makes gear noise going forward, but not backward.

Took it apart, thoroughly added grease by removing the plate that covers the bottom of the gear box (4 tiny screws.) Lubricated everything that I could access from inside.

No improvement noise wise. Grease pushing out front of gear box. Suspect front bearing missing.

It appears that further disassembly of gear box requires dropping the geared axle and gearbox out of the frame to open gear box.

That is beyond my pay grade.

I will have to live with the noise!

If there is a removable cover on the bottom of the gearbox once it is removed then the top of the gearbox lifts off from the top side of the frame.  However the boiler must be removed to do so.                         j

I mentioned yesterday that I would post some photos of the inside of another Samhongsa gearbox. Though the box I show is different than the one in Scott's loco it shows the bearings which appear to be missing on the front of his loco's gearbox. I don't think I have seen grease ooze out in the volume showing on his loco on any loco I have owned.  Let me add some context to the gearbox photos I am posting. A couple of years ago we were having a discussion about the Williams, Weaver / Samhongsa gearboxes and I was trying to show how little difference there was between the 42:1 and the 21:1 version of the similar gearboxes. The primary difference was that the 42:1 version has a single helix worm and the 21:1 version has a double helix worm. A single helix moves the worm wheel 1 tooth per worm revolution and a double helix moves the wheel two teeth per rev. The second difference is that the teeth on the worm wheel have a different skew angle. For our trains, a typical skew angle on a worm wheel's teeth for a single helix worm is about 5degrees and 10degrees for a double helix. You can see the difference in the photo where I placed a straight wire between the worm wheel teeth on the two gearboxes. Since I cannot see what is inside Scotts gearbox I cannot be assured that the worm is as contained as the one shown in my gearboxes you could remove the bearings from my gearboxes and the worm would still mesh with the teeth of the worm wheel till the teeth were chewed up. Thus the grinding sound that several people have spoke of.  I made some notes on a couple of my pix which I emailed to a supplier in Korea to see if they could supply said parts. They could not. Though Samhongsa made some very nice locomotives their quality control was not always what it should be. I would not be surprised if some gearboxes left the factory missing a bushing or having the worm wheels mismatched with their worm. I ran into that problem on the two gearboxes shown here the 42:1 and had a single helix worm and a worm wheel with the skew angle which matched the double helix and the 21:1 box had double helix worm and a worm wheel for a 42:1 box.  If you look at my pix you will see that the parts are marked with red and green markers. I did not want to mix any parts up so I removed and cleaned one gearbox and marked it's parts with red before I removed and cleaned the second gearbox parts and marked them with green. These locos were bought new in the box from different dealers years apart and this was the first time the gearboxes were removed. So there was little to no chance anyone swapped them after they left the Samhongsa  factory.  The two locos seemed to run fine with the wrong worm wheels but no doubt they would have wore out sooner as the contact patch where the teeth mesh was smaller on the mismatched gears.. I did swap them before I reassembled the respective gearboxes.  Surprise,, the current draw and start voltage both dropped in the locos which I swapped the worm wheels.         j         

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Wow, John. What a great description and pictures.

Let me ask this. Over the weekend I was able to adjust things with a flat washer on top and bottom of the worn out rubber bushing on the screw that holds the top part of the gear box to the frame. This corrected the angle of the dog bone connecting the motor to the gear box. So, now, there is almost no noise. Absolutely nothing like the screaming and grinding I started out with. The bearing grease is still coming out of the bearing hole though. You make the comment that without the bearings, the teeth will eventually grind themselves to pieces. If I (again) disassemble the engine and open the gear box and find the bearings are missing, where would I find new bearings ? Also, Trainz responded to my email offering to fix, give a refund, or exchange if I so desired. I really like the engine, but don't want to chance the gears grinding themselves to dust, or going to the trouble of opening everything up and not being able to replace the bearings. I'm contemplating sending the engine back and seeing if they can take it apart and replace the bearings, or just get a refund and look for one that doesn't have this issue.

Scott

Scott, I seriously doubt your engine is missing the bearings. That thing would be carrying on ferociously if even just one was missing. The reason you’re seeing grease ooze out the nose of that gear box is because it’s not a 100% sealed unit. The worm shaft in the gear box becomes a very effective pump impeller. So the grease is pushed towards the front of the enclosure. Beings there’s no seals, any tiny gap, and the grease leeches out,….it’s only going to spit out what it can’t hold, and eventually, the oozing will stop,….

Pat

Really glad that you were able to tame the noise.  I wanted to share two more ideas in this thread for your consideration, and for future reference.  First: From the photos, it's evident that the horned balls of your dogbone shaft rotate in a parallel plane.  Some folks swear that the horns should be at right angles to each other, to discourage the shaft from "ping-ponging" back and forth between the U-joint cups.  It's not difficult to make a new shaft, or even to cut your existing one, sleeve it, and reassemble with epoxy at 90 degrees.  Heck, some people use Toyota or BMW #0 vacuum hose to connect the motor and gearbox shafts, doing away with U-joints altogether.  If the hose has a snug fit, I would bet that this is very quiet, and the elasticity of the rubber might allow the motor to get a "head start" against the load when the slack is stretched.  Food for thought...

Second idea: This Weaver loco, and many of the Williams that hit the Forum with noise complaints are made of BRASS.  There's a reason they don't make tubas out of die-cast metal!  Brass resonates, and it will amplify any mechanical noise or vibration.  Auto sound and car customizer stores sell a material called DynaXorb which is a soft rubber matting used for sound attenuation.  You can buy it in one foot squares with adhesive backing.  A small rectangle of adhered to the inside of the boiler does a lot to mask the noise.  But as I said, you should address the root mechanical causes of the noise first, instead of just trying to cover it up.

Also, did we ever figure out what kind of motor your loco has?  Good post!

Scott the outer side of the bearings are likely flush with the side of the gearbox and should be visible if you wipe the grease away. Take a toothpick or small screwdriver and see how far you can push it into the opening that grease is coming from. The amount of grease oozing out is such that the bearing if there is wore out or perhaps the grease is coming from around the outside of the bearing.  The bearing and it's seat can wear just like the hole the the shaft passes through. The rear bearing and it's seat in one of the Williams 42:1 gearboxes I own was wore to the point the bearing was spinning in it's seat. However grease never flowed out the way it is on your loco. Perhaps you overstuffed the gearbox when you greased it.  I took some shim brass and cut a 3/16" X 3/4" wide ribbon and formed it around the outside of the bearing and clamped it between the two clamshell halves it stopped the bearing from spinning yet there is still some float so the bearing can align with the shaft without binding.  As far as new bearings go I was asking myself the same thing as I was patching my gearbox.  The shaft the worm is on is metric guessing around 3mm (not going to pull a body off tonight to measure)  and ball bearings are available starting around 1mm ID so I'm fairly sure with some searching you can find an ID which matches the worm shaft diameter.  They even come with flanges which would be a big help. I think that is the direction I am going.  However a thought I had a time or two is to try modifying a pair of the bushings from an American Flyer Alco diesel motor. The hole in them is near ,122" which is about .002 larger than 3mm they might work.     Think I like the idea of ball bearings better.   Also;  I think Ted is on to something about using vacuum hose  between the flywheel and the worm shaft. I was having a time quieting down my Williams PRR  2-8-2 with a 42:1 gearbox and I removed the dogbone shaft then substituted some 1/4" OD silicone tubing it made a big difference. I had to insert a snug fitting piece of brass tubing down the middle to keep it from stretching and bowing out at high speeds but I cut the brass tube so it did not touch the flywheel or the worm shaft and I floated the motor in 1/8" thick foam tape like the heating / air-conditioning people use.  Loco is quiet enough now that the wheels rolling on the track drown out the gearbox and motor.  Another thing I did was to line the boiler with that foam tape like Ted suggested. The 42:1 gearbox and having to spin the motor at 10,000rpm to drive 45smph can make quite a noise but I no longer hear the motor and gearbox I only hear the wheels roll.  One forgiving factor I was able to get away with a 385 motor because the 42:1 box creates 2.5 x the torque as a typical MTH 16:1 box.  Isolating the motor from any metal to metal contact with the boiler and chassis was of prime concern you can see the foam surrounding the motor. Same foam I used to line the boiler.       j

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Last edited by JohnActon

Thanks to everyone for all the great information. I thought I knew something about repairing Lionel and American Flyer engines, but you guys are the true gurus of train repair. I opted to return the engine to Trainz as they were gracious enough to take it back. I have to say that I am impressed with their customer service. I have purchased a number of items from them over the years, and this fortunately was the only item that had an issue. So, kudos to Trainz.com and thanks again to all of you. I learned a lot.

Scott

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