Different

The Athearn 60024 and A-Line 40005 gears will work in all of the LifeLike Proto:2000 Geeps except the GP38-2.  They also work in the BL2, FA1/FB1, FA2/FB2.  Not sure about the RS27 and U28B.  Also work in the Proto:1000 F3A and RS2.

The SD7/9's truck is a clone of the SD40 truck, and if memory serves the SW1200's truck is based on the Kato NW2's truck, so you might be able to use Kato parts in them.  Atlas axles are also very similar.

Athearn 60024 gears fit drives with 12:1 gear ratios.  Kato-style drives have 14:1 gear ratios.  The Athearn drive also uses fatter axles.

Scott Chatfield

Thanks Scott. I forgot to add

Thanks Scott.

I forgot to add the ALCO PA's.  Will the Athearn/A-Line Gears work with them.

And i'm confused, are the Athearn SD Axles different?  When I search for them, the searches return the 60024 Axles.  I have over 70 locomotives to do so I want to make sure I have enough of the correct ones to do this job.  Thanks.

Ken L. 

Athearns work

In the last couple of weeks I replaced gears in several P2K locomotives with Athearn gears.  BL2, GP9, FA1s.  When I replace the gears I replace them on all axles, not just the split ones.  I figure they will split eventually.  One of my BL2s had been running well for a couple years before the gear split.  The A-Line gears appear to be identical to the Athearn.  Athearn are a little less expensive.

The gears on my  P2K E7s, SD7 and one of the BL2s have not split.

Same axles

It's just that the ATH60024 _package_ says they're for the SD40-2.  They work in all of the _inside-bearing_ Athearn blue boxes, most of the Ready-To-Rolls, and some of the Genesis engines.

It _appears_ that the same axle gears should work in the Proto:2000 E-units, but they have smaller wheels (as do real E-units) with different stub axles that fit into the floating journal boxes.

I don't have a Proto:2000 PA1 to compare, but if memory serves they use the Athearn clone axles as well.  PAs had bigger wheels like freight engines.  I don't know if the model PAs have the stepped down ends on the stub axles.  They don't have floating journal boxes, do they?

I've replaced the axle gears on literally hundreds of Proto:2000s Geeps, FAs, and BL2s, and Proto:1000 F3As.  The failure rate is pretty close to 100%.  And on a bunch of Athearn blue boxes made in the '90s.  But I think I've only replaced the gears on two Proto:2000 E-units.

Scott Chatfield

As I recall; the Proto PA

As I recall; the Proto PA takes a similar but different axle from the 60024 style.

Do you guys drill the new gears?

No way I could get the Athearn gears onto Proto FA 1 axles without a press and I figured they’d just split with all that stress. 
 

Proto Pa

are a different size & the 60024 will not work.  The interference fit is the problem with these axles.  With the inside frame design, the whole axle sees tensile stress.  With the outside Athearn design, middle portion is not part of the fit, so it has a different stress pattern, and lasts longer.  With the Kato style, the axle is in compression.  Much less likely to fail.  

All of the Athearn clone type except the PA's use the 60024. The will still have a shorter life.  You won't likely be putting them through the stress cycles that the new engines can see, so they likely will be good for several hundred hours of running.

HOUSTON WE HAVE A PROBLEM!

OK, Just as a "test" I ordered only a few packages of tehe A-LIne 40005 replacement gears.  I took out four Wheels/Axles out of a P2K GP7 (no phase listed on this box) as well as a P2K GP 9 Phase III and the axles DO NOT fit ANY of the wheels?  Any ideas as to why?  

Thanks.

Ken L

The my are

Described as replacement for the Athearn parts that do fit the P2K gp7 & 9’s.  These require a press fit.  The P2K shafts are slightly larger so the fit is even tighter.  I have developed a system.  First hold the axle gear on a hard surface with one hole up.  Then put the first wheel shaft into the hole holding as straight as possible.  Remember the square axle bearing should be in place on the wheel shaft.  It take a hard push to get it started.  I just get it started.  Then hold the other wheel with the shaft up.  Put the second square axle bearing on the shaft.  Again press the previously assembled axle & wheel until it again just starts.  The I use a large variable gap wrench to close it the rest of the way.  My large wrench allows the assembly to remain straight and applies equal pressure to both sides.  With practice, you will know how much gap is left between the bearings & the axle gear.  The final step is to check and set the wheel gage with the proper tool.  At the best of times it leaves sore fingers.  But the above works well & I have done a number of engines worth at one setting.

kleaverjr

I'm going to earmark this discussion for further review in the future when i get time to sort thru my collection of P 2K locos.

Hope to hear more contributions to solving these axle gear problems.

Sure sounds like some of these VERY HARD press fittings would result in future splits of these replacement gears??

MikeHuges asked

I wouldn't use a drill. Measure the diameter of the wheel shaft and get a reamer from McMaster Carr that is close. Ream the gears by hand, do not use a power tool. If the fit is a bit loose use Loctite to hold everything together. Make sure you check gauge before the Loctite sets up. Just my opinion on doing this job.

Bernd

P2K axle gears & Athearn #60024 replacements.

Hi all. I have had a few p2k GP7/9 type locos with split axle gears & found Athearn 60024 replacements on ebay. Yes the Proto axle is slightly harder to fit in the 60024 gear but i carefully run a small drill (forget the drill bit dia.) through the 60024 gear BY HAND (DON"T USE A POWER DRILL), which allows the Proto axle to fit a bit easier. It's still a tight fit but haven't had any of my replacement gears split since. 

Just my method. May not work for everyone but it's worth a shot. 

P.S Here in Australia some of my ry modeling buddies had a similar splitting axle gear problem with their HO loco's brand known as TRAINORAMA but made in China with almost Proto clone drives I say Almost Proto clones as turns out some smart China mfr decided to use axle gear in these models with offset gears. Therefore the Athearn 60024 gears wouldn't work because the offset drive gears didnt line up with 60024 centre gear. The solution for these Aussie modelers came in having the mfr make replacement offset axle gears but with more cost to the modeler. Thanks. .

PA and Early E7-8s are different

I've replaced dozens of P2K axle gears over the years. The PAs have a unique, offset gear and they DO crack.

I've never reamed or drilled the replacement Athearn gears. As far as I can tell none of my replacements, some going on fifteen years now, have cracked. I use a PanaVice as an arbor press to seat the axles. Do not fully press the wheel back to the face of the gear. There will be about a .010 to .015 gap. Use a thin shim while pressing if one side closes up before the other is in. Use your NMRA gauge to get the flange distance perfect.

Below is a PA-1 axle and gear showing cracks. I'm not aware of an aftermarket replacement. Maybe there is one but I had lots of spares left over from dummy conversions. They aren't AS prone to cracking as the four axle models but some, obviously, did.

Good Luck, Ed

Proto PA axels

So there are no replacement gears for the PA's?
Are the original and later Walters models the same?

This isn't good news as I have quite a number of PA's (mostly not run a great deal as I was in between layouts). If I recall properly the Santa Fe PA was one of the original diesel engines that LifeLike chose to introduce their Proto 2000 line.?

And that color theme (SF) was a reason I chose to add to my C&O, B&O steam era engine gathering my early hobby re-entry. After all most of us as kids had some exposure to those Lionel ads featuring SF.

Gear Material?

BTW, what is the plastic gear material utilized to make these gears? Is it delrin??

I found this interesting/informative article on these POM plastics,..
https://hackaday.com/2016/03/03/materials-to-know-acetal-and-delrin/

And if you go down into the comments posted you see more about the shrinkage that results in our cracked gear problems.

BTW,... Ed (gmpullman) thanks for those great photos of the different gears for Proto locos !!

Hinged Trucks on some Proto 2K diesels

There appear to be some real knowledgeable folks in this discussion on Proto wheel sets.

I just wonder if any of them have run across this 'hinged truck' design I've found on a number of early E units??

https://forum.mrhmag.com/post/diesel-locomotive-truck-designs-hinged-3-axle-design-12217341

Proto 1000 gears and axles

Are the Proto 1000 axles the same size as the P2K ones. I believe I recently saw a discussion on this forum that might have hinted at that?

I have a P 1000 C-liner that I was looking at as a possible chassis for a 'pusher/helper' engine, and it has 2 cracked gears (ouch, I believe this was even a brand new engine I purchased long ago).

EDITED: Here is a link to that P 1000 discussion,... https://forum.mrhmag.com/post/proto-1000-drive-problems-12195374

P2K GP38-2 ???

So, 

why will the Athearn gear not work on the P2K GP38-2 ?

Because it's an Atlas clone

The Proto:2000 GP38-2's drive is a clone of the Atlas/China GP38/40 drive, not the Athearn.

Scott Chatfield 

It comes down to where is the frame/bearing

In gmpullman’s pix of the threes wheel sets, the left & center have the frame/bearing inside of the wheel between the axle gear & the wheel.  
the one on the left uses the axle gear sold by Athearn/Aline with the part numbers above.  This is the design used in the later Athearn BB engines- all versions that were inside frame.  It is also the basic design used in P1K & P2K engines that are inside frame, except the E units.  
The E design is the middle wheel set in the pix.  As show the gear diameter is clearly different.  The failure mechanism for this type is the same.  Thus they crack as well.  Finding replacements is more difficult.
The set on the right has the frame/bearing outside of the wheel.  In this last case the frame/bearing is not shown.  The axle gear part in this last case is longer by the width of the two bearings on the other two.  This is similar to the design of the Athearn outside frame application.  The failure mechanism is again similar.  The wheel shaft does not penetrate the axle gear tube as far.  The interference stresses are not directly imposed on the axle gear.  These do crack as well.  
As was indicated earlier, I change all the inside frame axles when I get an engine of that type.  Further, I replace the Proto wheels.  The shaft diameters are larger leading to higher interference stresses.  Driving the failure time.  

Most model diesels released today use a Kato clone design.  The frame/bearing is on the outside.  The difference in this context is the axle gear geometry.  The gear can be the same externally.  There is no longer a plastic tube that wraps around a shaft.  The gear axle has a solid plastic shaft that fits into each wheel.  In this case there is still an interference fit between the metal & plastic.  This time the plastic stresses are compressive compared to the tensile in the other option.  Much slower failure rates.  To gain that benefit, you would have to change the trucks.  Much cheaper to replace current axles & be prepared to replace again if & when they crack.

@Larry,.....question about P 1K C-Liner axel/gears

This is a C-Liner from Proto 1000. I was degreasing it the other day, and upon reassembly I noticed what I believe is excessive space between the gear and those little square bearings. It allows the bearing to become dislodged from the receptacle plate
 

Should some attempt be made to add some shims in there??

(Sorry for the lousy photos)

Check with the gearbox cover _on_

The design of the bottom gearbox cover is supposed to keep those bearings in place.  When the cover is properly installed, you should be able to slide the axle sets side to side a bit.  If they don't slide easily, the cover is under the bearings and not between them.  

Scott Chatfield 

It is a common issue

First make sure the wheels are in gauge.  Then when you have the wheels in place in the trucks, gently slide them side to side to be sure the bearings are in the slots properly.  Then put the bottom cover on.  The cover sides will hold the bearing in place.  

The gaps between the axle gear, the bearing and the wheels should be nearly equal on either side of the assembly.    larger gaps on one side contribute to this problem.

Got it Larry,...thanks a lot.

Got it Larry,...thanks a lot.