Remove the fuel tank cover, which is just stuck to the bottom of the chassis with double sided tape. Remove your couplers, Remove the two small/short screws that are located under the fuel tank cover. Lift off the shell. There are two screws located at the front and back of the chassis, near the couplers, remove these. Then, you may need to cut through the double sided tape to access two small bolts that secure the weight to the chassis. Now you can lift weight from the chassis.
The locomotive's instruction show an exploded view of where everything goes. Be careful removing the weight from the chassis as there are wires that run to the trucks; however, they generally provide enough wire so the weight can be removed and set along side the chassis. There is a U-shaped clip that needs to be removed from both gear towers. Follow the drive shafts from the motor to the gear tower and you will see the clip. I use a small straight blade screw driver to pry these clips off of the gear tower and this will provide you with access to the worm and two bearings.
NP 2626 "Northern Pacific, really terrific"
Northern Pacific Railway Historical Association: http://www.nprha.org/
I have a Lifelike GP7 and GP9 - both have the squeal problem. I am not sure how to remove the shell
so I can do some maintenance. I am hesitant to start removing screws until I know what to do. Any help/suggestions will be appreciated. Thank you
If you have a lot of the P2K Locos with the cracked gears, here's a neat little tool I found and also a source for the replacement gears:
http://www.alliancelocomotiveproducts.com/
The small fixture allows you to press the wheels onto the gears while keeping everything aligned. The fixture also gages the wheel sets for the proper width, just push the wheels till they bottom out against the fixture and they are good to go. I use a vise to press the wheels on.
No affiliation with the outfit making these, just a happy customer. I had about 14 of these 4axle Locos to do and this made the job much easier.
It could be missing worm gear thrust washers causing excessive end play.
Jim
cudaken Intrusting and timely post. I have a PK 1000 F 3 that squeals sometimes. I am 95% sure it is coming from the rear truck. Now that I have oiled the heck out of it it will only squeal ever now and then. But, the odd part, if I hold my finger in front of the engine (not pushing down) while it is running and hold it in places, it stops squealing? I have flipped it upside down and tried to move the wheels against each other and they do not want to twist. So what to you folks think, worm gear bearings? Ken
Intrusting and timely post.
I have a PK 1000 F 3 that squeals sometimes. I am 95% sure it is coming from the rear truck. Now that I have oiled the heck out of it it will only squeal ever now and then. But, the odd part, if I hold my finger in front of the engine (not pushing down) while it is running and hold it in places, it stops squealing?
I have flipped it upside down and tried to move the wheels against each other and they do not want to twist.
So what to you folks think, worm gear bearings?
Ken
Generally, squealing is caused by a shaft running through a bearing(s). So, that's what I think your problem would be.
cudaken So what to you folks think, worm gear bearings?
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
I hate Rust
I think so! Back to the Y-1.
NP,
Sounds like you've nailed it. Might be worth another shot of oil, otherwise go with Rob's direction.
I'm thinking the bearing between the worm gear and U-joint should pry apart if a fingernail can't separate it, but it's been a long times since I've had mine apart.
If you are going to be ordering Athearn parts anyway, it never hurts to have a pack of 60024 so long you own those locos -- it's gonna happen sooner or later. They're like a spare tire on your car. Eventually you'll regret it if you leave it in the garage.
Mike Lehman
Urbana, IL
NP2626When I determined that this was what was going on, it made sense to me as the noise did not sound like plastic gears grinding on each other. The noise sounded like bearing/shaft noise from a bearing being over-sized or worn out. So the fix is going to have to be replacement of the bearings. The question is going to be; how do you get the bearing off, that is between the worm gear and U-Joint?
So, I looked at the first four or 5 suggestions, took the engine down to the chassis and gear towers. I did not find the wheels to be loose;or, the problem. I looked for looseness of the flywheels and scraping of the flywheels against the weight and couldn't find a problem there. When I first bought the locomotives, I broke them in by running for 1/2 to 3/4 of an hour running in forward and then doing the same thing, running in reverse. So I feel the locomotives were properly broken in.
What I did do was put some lubricant on the worm gear and it's two bearings. This silenced the squealing. However, I'm finding that the noise is slowly coming back as the lubricant is being displaced in the bearings.
When I determined that this was what was going on, it made sense to me as the noise did not sound like plastic gears grinding on each other. The noise sounded like bearing/shaft noise from a bearing being over-sized or worn out. So the fix is going to have to be replacement of the bearings. The question is going to be; how do you get the bearing off, that is between the worm gear and U-Joint?
Guy,
That sounds exactly like what Rob was discussing, very likely the shaft bearings. You've eliminated the gears as an issues, since they're new and it's still happening. Try a drop or two of oil on each, then see if that helps. If not, Rob's laid out what the solution is for them.
I am in the same situation as NP. I have two P2K GPs that are ten years old and both of them squeal to some degree. Few ears ago I met a LHS owner who told me the problem with those engines was a too tight fitting between gears and worm. He cured the problem of the worst case with running the engine a few minutes with Colgate Regular tooth paste placed in the gears, cleaning the gears and lubing them. That worked well for some time but the problem is back now.
I recently put the Walthers replacement gear in both engine with no results. I will try lubing the bearing as soon as possible.
I like those engines for the details and paint job but I prefer to run my Atlas and Bachmann for the reliability and silent running.
Guy
Modeling CNR in the 50's
mlehmanI suggested the driver gears first, since it would not surprise me if they're part of the issue, even if it sounds like the loco still moves. It's a bit more involved to pull things apart and replace the bearings, so I tend to go for the easy obvious when it's not clear what the exact problem is... However, you're correct that this may likely require attention to the shaft bearings based on NP's description that it sounds more like a squeal than a squawk. But I've had the drive gear failures make all kinds of sounds, thus my approach to grabbing the low-hanging fruit first.
However, you're correct that this may likely require attention to the shaft bearings based on NP's description that it sounds more like a squeal than a squawk. But I've had the drive gear failures make all kinds of sounds, thus my approach to grabbing the low-hanging fruit first.
Hey, I understand not wanting to disassemble the whole thing. Having replaced my share of cracked axle gears and bad bearings, I've gotten to where I can do the repairs pretty quickly, but they're still not fun. The bad bearings emit a distinctive squeal, and no amount of lubrication will stop it for long. Once I hear the tell-tale screech though, I figure I'll have to eventually tear the thing apart.
Rob Spangler
wp8thsub BRAKIENow would that be with both LL and Walthers P2K Geeps? The reason I'm asking my Ohio Central P2K GP7 runs smooth and I'm thinking about buying 2 Santa Fe GP9s which is the older LL P2K Geeps in the Blue Box... Yes, both. Not all P2Ks have the same problem, so address on a case by case basis. Later ones are (anecdotally) also less likely to be affected by cracked gears.
BRAKIENow would that be with both LL and Walthers P2K Geeps? The reason I'm asking my Ohio Central P2K GP7 runs smooth and I'm thinking about buying 2 Santa Fe GP9s which is the older LL P2K Geeps in the Blue Box...
The reason I'm asking my Ohio Central P2K GP7 runs smooth and I'm thinking about buying 2 Santa Fe GP9s which is the older LL P2K Geeps in the Blue Box...
Yes, both. Not all P2Ks have the same problem, so address on a case by case basis. Later ones are (anecdotally) also less likely to be affected by cracked gears.
Thank ye.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
Rob,
I agree with your take that it may be a shaft bearing(s), although the one case .where I did have that in addition to the driver gears was solved by lube. I don;t doubt that this doesn't always work. And it's always hard to diagnose sounds over the internet without a sound file.
Since NP wanted to start with avoiding a teardown, I suggested the driver gears first, since it would not surprise me if they're part of the issue, even if it sounds like the loco still moves. It's a bit more involved to pull things apart and replace the bearings, so I tend to go for the easy obvious when it's not clear what the exact problem is.
Of course, pulling the axles and checking to see if they're all tight and not busted and the two half-axles aren't rotatable against each other on the gear is a good step toward diagnosis regardless of what's found. That might be the real first step before ordering any parts at all, as it could be one of those rare cases where the gears are still holding up. However, it's almost certain that NP will need the 60024 gears eventually, if not yet, given the history of this problem. It's always a good idea to have a package of these around if you're running P2K Geeps.
binder and Jeff,
True, 60028 will also do the job, but at more than twice the cost. There's usually not a thing wrong with the axles other than the busted gear, so using them sorta depends on how deep your checkbook is. It does look like the 60028 uses the new, improved wheels, a very good idea.
Using the older style (sintered?) Athearn wheels to replace P2K wheels would not be a good substitute given their grunge factor. In fact, if you do have a bunch of those old style wheels you want to replace, I believe these 60028s would be a good alternative to the slightly fancier NWSL option for the Athearn locos they fit, which is what many people did at some cost in the past.
wp8thsubThe bronze worm shaft bearings are of a poor quality and may not perform properly regardless of lubrication. There are two bearings on each worm shaft, so four total inside the mechanism. Athearn bearings fit perfectly and will eliminate the squeal.
Great information..Thank ye kindly.
Now would that be with both LL and Walthers P2K Geeps?
This is a common problem with some P2K Geep mechanisms. Judging by the comments here and on some other forums, it remains frequently mis-diagnosed.
The bronze worm shaft bearings are of a poor quality and may not perform properly regardless of lubrication. There are two bearings on each worm shaft, so four total inside the mechanism. Athearn bearings fit perfectly and will eliminate the squeal. Athearn sells packages of the bearings, or you can scrounge them from old mechanisms.
Note that the Athearn parts now come in different sizes. There used to be one size of bearings both for the axles and worm shafts. Recent Athearn mechanisms apparently continue to use the same bearings for the axles, but the worm shafts are of a slightly smaller diameter so the parts no longer are interchangeable with P2K. I found this out trying to use late Athearn mechanisms for parts. If the Athearn donor mechanism has a plastic worm, use its axle bearings on the P2K worm shaft. Older ones with the brass worm are fine. The bearings sold separately seem to work also.
I have made this substitution on a number of P2K locos, and it has permanently stopped the squeal every time.
Part #ATH40028
Athearn DOES make a complete wheelset, the plastic gear and the two wheels with stub axle, fully assembled. I can't quote the part number right now, but it is a straight drop-in replacement for the P2K wheel/gear set. I have done this on most of my P2K 4-axle units, just two to go. The Athearn wheel set makes the job easy, just pop off the bottom plate of the truck, pull out the old geared wheels, add the new ones, a SMALL amount of lube oil, place the cover back on the truck and off you go.
An obvious reminder that many of us forget - keep a clean rag or paper towel handy and wipe the oil off your hands before handling the locomotive. Oily fingerprints on the paint really look bad!
If it's the infamous cracked gear squall, then yep, Atheran has the right parts now that Walthers no longer supplies replacements. However, it's not a complete wheelset, just the center gear.The Athearn part # is 60024 (for a package of six). It says it's for a SD-40 but they work fine for this app and are the right ones.
You pull the half-axles off the old, cracked gear and push them onto the new gear, then use the NMRA gauge to ensure gauge is correct once reassembled. There's is no need to pull anything from the loco, except for the bottom cover on each truck. The wheelsets lift right out and go back in once repaired, then snap the cover back on.
I'd try that first. The rest of the suggestions require pulling the shell. I suspect that even if there's an issue inside, it's likely that the final drive gears on the drivers need to be R&R anyway.
Good things above. These are possibly motors with open commutators. Sometimes when you lube them these commutators can get moved. So check to make sure they are in good position and that the motor bearings are well lubed.
To lube these I know that I have to take the weights off. So just make sure the weights aren't touching anything like a fly wheel or that one of the wires isn't touching.
Richard
Also check that the plastic U-joints and shafts are not slipping on the metal motor and/or gear tower worm shaft. This usually occurs as you increase the load on the engine.
Sounds like the flywheel or motor shaft needs a small drop of oil.
If the noise continues check the flywheels to insure they're not loose.
As far as the crack gear issue you will hear a "click,click,click as the engine is being ran.
Adding to mobilman44's comments, I have had a similar experience with essentially "new" locos that have been run very little time, then sit on the layout, unrun for years. After cleaning and lubing them, I found that I still needed to break them in since I had never really done that in the first place. So, I simply ran them for a good 20 to 30 minutes, forward and backward, and that essentially solved the squealing problem.
Another idea is to try to isolate the squealing to the forward or rear truck or to determine if both trucks are producing the squealing.
Just some additional thoughts.
Rich
Alton Junction
Hi,
I am very familiar with these locos, having 12 of them at one time (atsf & IC). There are two strong possibilities for the noise. In no particular order:
- A couple of mine resided in a display case for years, and squealed loudly when I took them out to test (before I sold them). I "lubed and tuned" and the noise went down, but not away. Then I realized that there was a hidden bearing point on one of the shafts (leading from the motor to the gear drives. With a touch of oil, all was fine.
- The other problem affected many/most of the older P2K GPs and some other units. The wheel sets became loose (broken) so that when removed, one wheel would turn while the other would not. They are supposed to be solid, so if one wheel turns, the other will as well. Most of mine had the problem - some on one or two wheel sets, a couple with all wheel sets. At that time, Walthers supplied new wheel sets free of charge. It is my understanding that now, replacement wheelsets can be obtained from Athearn.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
I have a pair of these locos that are probably 10 years old. They sat idle for 6 years while I was back into building and flying R/C airplanes.
Now both of them squeal when used. One more than the other. I have lubed the gears in the trucks and worm gears to no avail. My next step would be to completely tear down the drives and if I can keep from doing this, I would be happier.
Both maybe have 4-5 hours of running time. these are great locomotives, nicely detailed and used to run like finely tuned pieces of equipment.
Any suggestions?