MTH steam engine & traction tires

I don't believe a traction tire would cause a derailment, unless it was loose on the driver and about ready to fall off.  Does the loco derail going in the opposite direction?  If not, then your track is the problem.  You should be able to crawl through the Ross switch unless there is a problem with continuity of the center pickups, or if it is 2-rail/3-rail one of the drivers is not grounding properly.

As far as I know the traction tires are tight on the wheels. The track is an 042 curve that I have a problem with. Both engines are MTH 4-8-4 steam engines used on 3 rail track, there could be a spacing issue with the center rail pick-up rollers. I have used an SD-70 ACe diesel and have no issue with speed going through the Ross switch.

Should I replace the track with Gargraves curves? I have less problems with Gargraves track.

Lee Fritz

Some RealTrax sections have a misalignment problem with the rails at the joints.   There could be a mis-match on the outer curved rail that could cause the flange to climb the rail.  Does it derail in the opposite direction?  If not, then I would check the joints carefully.  Also check to see if the traction tires are smooth, without any bumps on them caused by foreign material lodged under the tire. It can cause the driver to lift slightly, but I would think you would notice a wobble.

As for the pickups, lay the loco and tender on its side or in a cradle and see if it will power up with one lead on a pickup roller and one driver.  Let it power down, then check the other roller and one driver.  If both work, then check one roller and each driver separately.  Also check the tender wheels as the PS2 harness likely has a ground in the tender.  See where the loco is picking up the ground connection (outside rails) to determine if there is a sufficient ground. 

I will check it out today and see if the traction tires and rollers are in great shape or not.

FYI; I am using Lionel or K-Line 042 curves. I don't have any Realtrax or Fastrack as I don't like to be limited by plastic roadbed track sections. I prefer tubular track because you can cut to fit the pieces. Plus I grew up with tubular track.

I have tried Fastrack and don't care for it! 

Lee Fritz

Checked the engine and tender and everything looks good, no problems with traction tires. Tried going in the opposite direction with the engine and it still had a slight wobble in the affected area. So I took up the 042 track and put down Gargraves 042 curves.

Lee Fritz

There's usually a groove in the wheel where the tire is suppose to sit, check to make sure each tire is sitting in the groove.

I had an engine I replaced the tires on and the replacement tires were wider than the groove, thus not sitting down.  The engine kept derailing until I turned it over, and while running, trimmed the tires using a razor blade.  Once I got them to fit in the grooves all derailments ceased.

Bob Delbridge posted:

There's usually a groove in the wheel where the tire is suppose to sit, check to make sure each tire is sitting in the groove.

I had an engine I replaced the tires on and the replacement tires were wider than the groove, thus not sitting down.  The engine kept derailing until I turned it over, and while running, trimmed the tires using a razor blade.  Once I got them to fit in the grooves all derailments ceased.

That's not my issue! I looked at the traction tires and other then a little wear they are still good, checked the other wheels as well and all is good. Like I mentioned in my first post it only happens at one area.

I have a set of new tires but I am waiting until one of the tires falls off, as that is what usually happens with this MTH model.

Lee Fritz

I had to replace traction tires on MTH steam locomotives that had been in storage for more than a decade. The tires weren't coming off completely, but were rising out of the groove causing a wobble. This would happen on a curve.

Keith,

I think my issue is more of a track issue after looking at both engines. On one engine the traction tires are old but have not seen any distortion of the tire after looking at it very closely. The engines run great other then one place on my layout.

Have replaced some of the track with Gargraves track and the problem seems to have gone away. While on the subject of track I would say it is best to keep transition sections(adapter pins; Gargraves to tubular) away from curved sections of track, when you have transition sections keep them 2 or 3 track sections from any curve if you have O gauge tubular track to Gargraves track.

Lee Fritz

The track gauge could be  off or a wheel could have moved on the axle, so that the flanges are too far apart to make the curve.  I've had both happen.

RJR posted:

The track gauge could be  off or a wheel could have moved on the axle, so that the flanges are too far apart to make the curve.  I've had both happen.

That can happen even with MTH Premier engines? I might expect it from Railking engines.

Like I mentioned earlier I think the track is off at the transition area.

I replaced the O gauge tubular 042 curves with Gargraves 042 & Gargraves straight track and don't have an issue so far.

Lee Fritz

phillyreading posted:

RJR posted:

The track gauge could be  off or a wheel could have moved on the axle, so that the flanges are too far apart to make the curve.  I've had both happen.

That can happen even with MTH Premier engines? I might expect it from Railking engines.

Like I mentioned earlier I think the track is off at the transition area.

I replaced the O gauge tubular 042 curves with Gargraves 042 & Gargraves straight track and don't have an issue so far.

Lee Fritz

There is nothing magically different between an MTH Premier and an MTH Rail King locomotive. Wheels can be out of gauge on either. Don't assume that one is made better than the other and will result in fewer problems.

The reason your Gargraves track seems to have solved the problem is that you changed the rail profile enough so that the traction tire is no longer touching the metal rail in the same way. But to be clear: The traction tire is very likely the issue, as others have suggested.

As far as I know the traction tires are factory or original. I can change them but don't want to change them unless really necessary, I have the new traction tires and small wrenches so no problem, I just didn't want to do that if I don't have to.

FYI; seems like MTH large steam engines eat up traction tires.

Lee Fritz

Lee

Is your problem resolved?

phillyreading posted:

As far as I know the traction tires are factory or original. I can change them but don't want to change them unless really necessary, I have the new traction tires and small wrenches so no problem, I just didn't want to do that if I don't have to.

FYI; seems like MTH large steam engines eat up traction tires.

A generalized statement NOT based on fact, in my opinion. I have LOTS of "large steam engines" from MTH, Lionel and Sunset/3rd Rail, and rarely have I ever lost a traction tire. Then again, our sharpest curve is 072, in only one location.

Lee Fritz

Oman posted:

Lee

Is your problem resolved?

Problem solved. Installed Gargraves curves and a few sections of Gargraves straight track. The tubular track at the curve was out of round or enlarged from from being taken apart several times.

Lee Fritz