MTH Restoration Big Boy - am I too picky?

Peter C,

You're running at very slow speed over a switch. Not surprising to me that you see some variation in speed. Does the engine run smoothly on a straight section of track where there are no switches?

MELGAR

dirty wheels, track?

MTH will never compare to Legacy for low speed control

In my experience, many MTH Steam engines and Diesels never level out smooth until after 5 MPH.

Thank you for your replies! The jerky low speed operation still occurs on straight track without switches. The wheels & track are clean and the engine has been oiled.

It is important to note that this engine does run VERY smoothly at 6 scale mph and above. In fact, it tracks much better through O-72 switches and “S” curves than my Lionel Legacy Big Boy, especially in reverse!

At very low speeds, those hesitation moments seem to occur at about the same 2 points in the drivers’ rotation.

Some gorgeous running gear!  Congrats on the engine!

Can you please post a close up picture of the end of the tether coming off of the engine.  Trying to determine if there is damage to mine.

thanks

It has ro be broken in. Let it run at 3/4s speed minimum for about an hour. You can use rollers or have it haul a train.

Pete

Agree with above, ….I’d run it at about 25-30 SMPH with a train for a right good while and then re-examine the situation…..

Pat

As noted above it needs some break in time. Lube everything and run it for a couple hours at 25-45 mph. After that it should smooth out and run down to 3 or so MPH smoothly.

Aside from break-in, it looks to me that the brakes may be contacting the wheels at two times during the video - first the 4th driver on the rear engine and then the 4th driver on the front engine about 4 seconds before the end of the video.

MELGAR

Melgar, I wondered about the brakes hitting the drivers! When you say “4th driver”, are you counting from the front so that you’re referring to the rear driver on each engine? That would be the driver that has slightly more diameter due to the traction tire.

@Peter C posted:

Melgar, I wondered about the brakes hitting the drivers! When you say “4th driver”, are you counting from the front so that you’re referring to the rear driver on each engine? YES. That would be the driver that has slightly more diameter due to the traction tire.

Yes. Counting from the front driver and going rearward. It looks to me that at about 4 seconds into the video, there is no clearance between the brake shoe and the 4th (rearmost) driver of the rear engine and then at about 11 seconds into the video there is no clearance between the brake shoe and the 4th (rearmost) driver of the front engine. Again, counting from front to rear on each engine. Also, as others have said, the engine needs at least one hour of run time for break-in. Steam locomotives, with their multiple axles and connecting rods inherently have high driveline friction when new - and this locomotive has two engines... Check the brake shoes and then run it for an hour.

MELGAR

The traction tire driver is VERY commonly a problem with the brake shoes, Lionel has shipped me several locomotives where they dragged so bad that it stalled and blinked out a motor stall!

Bossman284, here are a couple of photos of the wireless tether in the back of my Big Boy locomotive. Let me know if these photos are what you’re looking for.

Peter

- Be sure traction tires are fully seated
- Oil pivots on side rods
- stop drivers with the counterweight at 6-o’clock and note if any wheels are out of quarter.

@Peter C posted:

Bossman284, here are a couple of photos of the wireless tether in the back of my Big Boy locomotive. Let me know if these photos are what you’re looking for.

Peter

Exactly what I was looking for.  thank you.

Possibly siderods binding, or brake shoe rubbing traction tire as previously mentioned. When i was at MTH i used a dentists mirror to see  the siderods in motion from the bottom , usually it was side play wheels moving from side to side.