671 Repair Questions - 1946 turbine

You caused me to pull out my original Lionel Service Binders and sure enough, they only cover the 1947 671 and do not show some of the 46 specific details. Same goes for the K-Line and Greenberg collection. The '46 726 is very similar, and Olsen's actually went through and took the ' 46 726 instruction sheet and updated it to be applicable for the '46 671. I can't vouch for it's accuracy to be 10000000%, but it looks like a respectable effort.

http://www.olsenstoy.com/cd/locos/671-2.pdf

I haven't uncovered anywhere where Lionel lists the explicit wheel gauge out side this generality:

Hope this gets you on the right track.

Red atomic motors are rare. Don

Hi George, lots  of questions.  Since I am on cell phone I will make this brief. More later if you want it. 
1). 1946. Horizontal e unit and smoke bulb tell for sure. 
2). No balls in the bearings. Since this is a spur gear drive motor there is little axial thrust, so no thrust bearings needed. In ‘46 Lionel was thinking, incorrectly, that the oilite bearings would never need lubrication. So they made little provisions to oil them. Later versions of that motor have a hole drilled between the bearings to add oil. You may want to drill that hole as it makes life much easier. If you are interested I can send photos later. 
3). End play on that motor is not a issue as long as commutator doesn’t not hit brush plate. Again, no axial thrust as no worm gear. 
4) spur gear would be removed from armature shaft with proper size gear puller.   I would recommend against this as I believe it will be difficult to reinstall without damaging the commutator. 
6). Normal wheel spacing on most post war locos is axle flush with wheel hub on both ends. When I get home I will check if I have recorded Wheel gauge at Intersection of flange and tread. 

Lionel never produced a service manual for the ‘46 turbine, there is a parts list.

Replacing an axle worm wheel on this engine is uncharted territory.  There were only two locomotives built like this one. They are the ‘46 turbine and the ‘46 Berkshire.  The worm wheels and the side rods are parallel drive linkages. Everything after these two locos used a single worm wheel and drives with the side rods. The question I have never been able to find anybody to answer is how close do the worm wheel teeth have to be in alignment with the side rod holes to get the front and rear driving axles to work together?  You could just remove one of the worm wheels and you would have a drive train almost like ‘47 and later turbines and Berkshires. Or you could change the bad worm wheel and teach the rest of us how it is done.

@bmoran4 posted:

The '46 726 is very similar, and Olsen's actually went through and took the ' 46 726 instruction sheet and updated it to be applicable for the '46 671.

I did find spot that and found it to be helpful.

I haven't uncovered anywhere where Lionel lists the explicit wheel gauge out side this generality:

Hope this gets you on the right track.

What gives me pause is that I normally measure from the intersection of the tread with the flange, to the same location on the opposite wheel - just as shown above. With a nickel tire on there (especially a tire with some "wrinkles" to it) you can't measure from that point - no way to get my caliper down in there!

This is a drawing I made quite some time ago,

I forget the exact reason - but it shows my concern with gauging wheels that have (in this case, nickel) tires on them. I believe I will be better off just taking measurements on existing conditions with the wheels I will be removing (perhaps from the backside of the flanges or the outside of the nickel tires), and then shooting for the same measurements upon reassembly. 

To top things off, one of the flangeless wheels took a hit at some point in time, and the nickel rim now has a bit of "wiggle" to it - not loose, just a wrinkle so to speak. Knowing that these wheels don't really make a lot of difference in the whole drive train scenario, I can live with it. But since I have to remove that wheel to get the rear wheel off, I may as well take a shot at straightening it.

Thanks for replying!

George

@scale rail posted:

Red atomic motors are rare. Don

I have heard that argued both ways and I simply don't know! I never got too concerned over it since I never sell anything anyway. That said, if it is rare, I would take pains not to mess it up!

I checked my notes on the 671.  I show the wheel gauge, measured at the intersection of the tread with the flange, should be 1.246”.  The back to back dimension on both the flanged and blind wheel sets, is 1.100”.  I have more detailed dimensions on the 681 wheels if you want them. The 681 wheel is the steel version of the 671 die cast wheel with the tire. The design change was to get a magnetic wheel used with Magni-traction. 

@David Johnston posted:

 

The worm wheels and the side rods are parallel drive linkages. Everything after these two locos used a single worm wheel and drives with the side rods. The question I have never been able to find anybody to answer is how close do the worm wheel teeth have to be in alignment with the side rod holes to get the front and rear driving axles to work together?  You could just remove one of the worm wheels and you would have a drive train almost like ‘47 and later turbines and Berkshires. Or you could change the bad worm wheel and teach the rest of us how it is done.

David has more experience working on these locos than I do.  Personally, I don't believe it would run very well with only one.  Instead of trying to replace just the worm wheel, I would hunt around on auction sites, postwar parts dealers, etc., and try to come up with another geared wheelset.  It should already have the bearing blocks installed too.  A complete wheelset like this won't be cheap, but this loco is worth it!

The unique beauty of this design is that you can replace a wheelset without pulling or pressing anything.  The bottom of the chassis comes off and you can slide the new wheelset right in, in place of the old one.  Many fine brass models in all scales are constructed like this.  My guess is that just replacing the worn worm wheel will restore the loco to factory operation.  You should know in advance that these '46 models tend to run slower and with more noise than the later ones.

I understand exactly what David is saying about the "timing."  If you get a new wheelset, please try to compare it with the worn one.  See if you can discern whether the position of the gear teeth is the same relative to the driving rod bolt.  In other words, is the bolt perfectly lined up with a tooth or valley?  Is it off by the same number of degrees?  Etc.  I imagine that it will be difficult to measure precisely.  However... if the timing of the front and rear axles are way off, the side rod will be trying to pull the wheel forward before the worm gear applies pressure to the next tooth, or vice-versa.

My guess is that they were all set up the same way at the factory (or should have been.)  That's why I'm suggesting that you install a new-old-stock geared wheelset, and not try to replace the gear yourself.  I've heard a million times that "some of these run better than others."  I think the gear-and-rod timing might explain why this is the case.  Look forward to updates on this thread!

@Ted S posted:

I understand exactly what David is saying about the "timing."  If you get a new wheelset, please try to compare it with the worn one.  See if you can discern whether the position of the gear teeth is the same relative to the driving rod bolt.  In other words, is the bolt perfectly lined up with a tooth or valley?  Is it off by the same number of degrees?  Etc.  I imagine that it will be difficult to measure precisely.  However... if the timing of the front and rear axles are way off, the side rod will be trying to pull the wheel forward before the worm gear applies pressure to the next tooth, or vice-versa.

The unique beauty of this design is that you can replace a wheelset without pulling or pressing anything.  The bottom of the chassis comes off and you can slide the new wheelset right in, in place of the old one.

Ted, that's a great summary of the situation. I will add a second post addressing that, shortly.

Now, here's a top and bottom pic of my 671 chassis. I do not see any way to change out a wheel set short of pulling wheels, and in the case of the rear/front wheels, a wheel and a worm gear. What am I missing?

 TOP VIEW BOTTOM

George

I don’t know George, just taking a peak at your pics, those worm wheels don’t look all that worn out....in fact, they look fine.....was the worm shaft skipping?...making the mechanism lock up?....I’m just making one suggestion, then I’ll leave this alone, there’s already some fellas helping you out,.....I’d grease it, oil it, put it all back together and see how she does....take what??.. .....45 minutes to get it back together to run?....those earliest turbines ain’t built like the Berks where you can drop out a wheel set for service.....you’re quite correct, you got to pull wheels, press out shafts, etc. etc......that’s all I got .....

Pat

Just sharing what I could readily put my hands on (not that it solves your wheel pulling problem, but it does show that the early 726 has plates holding the axle bushings in:

From top to bottom:

'46 726

'46 726

671 with direct single worm drive

726 with direct single worm drive

I'm also with @harmonyards stating that from what we can see in the pictures, this doesn't warrant the gear replacement work you suggested. I would clean it, lube it, and send it.

@harmonyards and @bmoran4, the more I look at the rear worm gear, the more inclined I am to agree with both of you! Here's a close-up of that gear

- there really is very little wear - what is there is mostly visible in the center. My giant magnifier can see the wear MUCH better than this picture from my little Canon snapshot camera can show. Not enough to cause any skipping, just wear from play over the years. Interestingly, the front worm gear shows no signs of wear??? I hastily reached the conclusion to replace this gear knowing that I was 100% going to remove the right rear driver to add a shim to eliminate wheel dragging on the frame, and thought I might as well put a new worm gear in place while I was there. With new eyes critiquing this replacement, I am inclined to agree - I will add my shim, then reassemble and reassess.

That said, read my next post.

George

Gauging of Wheels

The picture below is a summary of the measurements I have taken using a caliper. What I learned from this exercise is that there is much as .063” variation when taking absolute measurements between measuring points A) distance from flange to flange, caliper contact points, and B) distance between inner edges of the nickel rim. I might add that B is really an estimation since the nickel tires mostly appear to be situated evenly with the intersection of the wheel tread and wheel flange.

Surprisingly (to me), the most consistent measurements seem to be from the inside flange-to-flange measurements, having only a max variation 0.003” This appears to be any easy measurement to obtain when gauging wheels, and in my case, the most consistent.

Next I need to find suitable washers to add to eliminate the side-to-side play so prominent in my rear and front drivers – that situation can’t bode well for keeping the worm centered on the worm wheel! I also need to consider the fact that the left rear wheel flange is rubbing on the frame.

Theoretical Discussion about replacing one or both worm gears (decided not to do this!  

Now, about the seating of a new worm gear, should one actually decide to attempt it... To @David Johnston's point, what is the requirement for matching up the positions of the front and rear worm gears with respect to the front and rear wheel drive rod mounting holes? As @Ted S stated, a situation could arise where the rear driver is really using just the side rods to drive the front wheels, i.e. no direct drive through the front worm gear at times, resulting in what I would think would be some very jerky motion, or some gear grinding (growling?) at times. To solve this, I took the easy way out and counted the worm gear teeth, finding 23 in total. That seemed such a strange (odd) number and having older eyes, I counted gear teeth six times, 3 front, 3 rear, so I’m comfortable with the count. That would indicate there are 360/23 = 15.65 angular degrees between teeth.

Now if I could identify the absolute need to mount each worm gear in exactly one spot, or in this case one of 23 same exact spots, then my maximum variation would be half the angular distance between gear teeth, or + 7.825 degrees - anywhere within that + range should produce acceptable performance. Next I measured the angular variation allowed by the “slop” in drive rods, and their associated mounting hardware. I used the evenly spaced wheel spokes to accomplish this – I counted 16 spokes, or 22.5 degrees between spokes. This is where measuring gets “iffy.” I connected the front and rear drivers on one side only using the hardware that came with the train – no wear marks appear on the screw shoulders that attached the drive rod, no obvious wear on the inside of the drive rod mounting holes, but that can be hard to see. By holding the front driver in a fixed position, I moved the rear driver CW and CCW, and found the variation to be about 2/3 of the distance between adjacent wheel spokes, or 0.667 x 22.5 degrees = 15.008 degrees. That’s roughly double the variation that could be realized by mounting a worm gear in a worst case scenario. My conclusion is that you can’t screw it up!! Is my nerd showing yet?

That said, I am comfortable with all my measurements, but less so with my conclusion. This is where I could use some confirmation or explanation of what I might have thunk wrongly!!

While I'm waiting to hear back some thoughtful response(s), I think I'm ready to quit talking and take some next steps.

 George

@GeoPeg wow, that's some amazing detective work!!

First let me apologize.  Pat (as usual) is right.  Apparently only the Berk has a removable "bottom plate" that allows you to slide out the wheels and axles as an assembly.  That's what I was thinking of.  From your photos I'm disappointed to conclude that the Turbine didn't benefit from this design.  So if you ever do need to change the wheels, gear, etc., you would have to pull and press them as with almost all Lionel trains.

Regarding your angular measurements... If I understand you correctly, you're saying that there's enough "slop" in the side rod holes, that the next tooth in the worm wheel will ALWAYS be picked up by the thread of the worm, before the outside of the wheel is pulled forward by the rod.  This is an amazing discovery, because it pretty much busts my theory that different "timing" between the front & rear worm wheels is the reason why some of these locos run very well while others are noisy and balky.  Maybe someday the true cause of the widespread variation in running quality will be found!

I'm not surprised at your 23-tooth count.  There's a design philosophy that says if you want the mechanism to be long-wearing, use prime numbers for tooth counts so that over the life of the mechanism, wear is distributed evenly over the whole gear.  In this case, it looks like it worked!

One more thing-- you don't necessarily have to pull the driver.  Try wedging a slippery plastic "bread clip" between the wheel and the frame, or even inside the chassis between the worm wheel and the frame on the opposite side.  (You can also use material from a plastic milk jug, etc.  Cut it into a circular shape smaller than the driving wheel.)  Among Berkshire owners this is known as the "bread clip mod."  Do this as a temporary fix to see if it improves performance.  And take comfort in knowing that If you do have to remove the wheel, you have at least 7 degrees of forgiveness when it comes to re-mounting it "in quarter."  Great discussion here!!

George, ...one of the fellas above, mentioned something about if the axle is flush with the edge of the wheel where it pokes through, that’s about where it needs to be.....not sure if that was David or BMORAN4.....but again, before I pulled any wheels, or did anything else drastic,...I’d get it down the rails under it’s own power, and see what’s what,...unless you’ve already done that...

Pat

@Ted S posted:

Regarding your angular measurements... If I understand you correctly, you're saying that there's enough "slop" in the side rod holes, that the next tooth in the worm wheel will ALWAYS be picked up by the thread of the worm, before the outside of the wheel is pulled forward by the rod.  YEP!! This is an amazing discovery, because it pretty much busts my theory that different "timing" between the front & rear worm wheels is the reason why some of these locos run very well while others are noisy and balky.  Maybe someday the true cause of the widespread variation in running quality will be found! As in ALL theories, the proof is in the pudding. It wouldn't surprise me for somebody else to challenge my conclusion and provide a more accurate one!

I'm not surprised at your 23-tooth count.  There's a design philosophy that says if you want the mechanism to be long-wearing, use prime numbers for tooth counts so that over the life of the mechanism, wear is distributed evenly over the whole gear.  In this case, it looks like it worked! Did not know that! Now I have to forget something else to make room for that new found bit o' knowledge!

One more thing-- you don't necessarily have to pull the driver.  Try wedging a slippery plastic "bread clip" between the wheel and the frame, or even inside the chassis between the worm wheel and the frame on the opposite side.  (You can also use material from a plastic milk jug, etc.  Cut it into a circular shape smaller than the driving wheel.)  Among Berkshire owners this is known as the "bread clip mod."  Do this as a temporary fix to see if it improves performance.  And take comfort in knowing that If you do have to remove the wheel, you have at least 7 degrees of forgiveness when it comes to re-mounting it "in quarter." Too late for that, I have one wheel off already! As I pulled it, I realized I don't have wheel cups for this puppy!! A quick call to Jeff and he had a remedy in hand before I could even blink. He has a single set of universal wheel cups for my press - fits all 5 wheel variations. I will be using 671M-23 thin washers, about 0.010" thin to be specific. That way I can easily stack them to get the fit I want to reduce lateral play, eliminate the flange from rubbing on the frame, and help to keep the worm centered on both axles. I will be pulling all wheels before I'm through 

Great discussion here!! Yes it is! And BTW, that horizontal e-unit is the best thing since sliced bread. The spring resolves a couple of issues - horizontal mtg to reduce overhead, it eliminates the unsightly lever stick up through the boiler, and it would seem to eliminate the "hanging pawl" syndrome where the e-unit remains stuck in a gear until thumped or tapped - my experience with that is that the drum gets a single groove carved into it by the snapping action of the pawl - kind of cuts into the plastic a bit and leaves a very narrow "shelf" for the pawl to rest in when the power is cycled. A single edge razor blade cleans that up easily, just got to cut slowly!

A  

@harmonyards posted:

George, ...one of the fellas above, mentioned something about if the axle is flush with the edge of the wheel where it pokes through, that’s about where it needs to be.....not sure if that was David or BMORAN4.....but again, before I pulled any wheels, or did anything else drastic,...I’d get it down the rails under it’s own power, and see what’s what,...unless you’ve already done that...

Pat

I did take it for a test run before and after motor cleaning - it went from a very rough running motor to a very smooth running motor. I probably could have slapped things back together at that point and moved on, but it's not in my nature to pass up any improvements I can add along the way ... and the wheels were rubbing a bit ....

Since all my axle ends were indeed even with the wheel hubs, and the wheel/track wear patterns looked like they were in the right spot, I will simply rely on that  method to get the gauging correct on reassembly.

Also, I found that it wasn't just a bent tire on one of my blind drivers, the wheel was also bent, so that one has to be changed out.