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I have an older HO P2K GP20 that I recently put a decoder in. All was fine for a while. Now the front truck assembly ( I think) sounds like a bird on steroids. I've removed the shell, I checked the geared drive assemblies (and replaced 3 cracked gears). My frustration is that I know something is binding or rubbing, but I can't get to the worm gears, etc, because I can't find any screws or tabs to disassemble the engine and body. I assume the plastic bottom cover plate that says "LifeLike" will come off somehow, but I don't want to break it or anything else. Any help is appreciated!
The worm gears are the metal ones on top driving the rest of the gears going to the wheels, are we on the same page? I guess I'm not understanding what you all did??
What cracked gears did you replace ? The ones that went bad were on the Axles of the wheels, is that what you did?
first check or replace all 4 axels. common issue with P2K.
I have 7 p2k Gp18s and will assume the Gp20 is simmilar...
when you put the covers back on the trucks make sure that the brass squares on the axels did not fall between the metal plate and plastic housing. the brass square should ride in the slot of the steel plates.
If that looks good and you still want to check the worm gears you will have to basicly take the whole loco apart. Remove the fuel tank cap and you should see 2 brass screws. remove them. look near the underside of the front and rear of the frame their may be screws that hold the weight to the frame, remove them.
Depending if the loco is DC or DCC you will have to remove the wires to get the weight off the loco. now you will have full access to the driveshafts and clips that hold the trucks to the frame. once the clips are off the worm gear will pull out and the truck will drop out. I suggest trying some lite hooby oil before you go thru all of this.
Thanks for your input. I replaced the gears on the axles. Now I want to get inside to see the worm gears, etc. My problem is that I can't get the fuel tank cover off. Pretty dumb, eh? Does it pry off or slide off? Never had that problem, before.
Trent, Im going to check the axles as you suggested. Are they easy to come by? I did a light lube originally.
I have replaced all my axels in my P2K locos. Gp18 x7, and Alco FA x4 the early run Proto 2000s had cracked gear issues that were later fixed. Still you may find a cracked gear in the newer run models but no where as often as on the older stuff.
On my GP18s the fuel tank is held on with double sided tape, it just takes a slight force to get it off. May want to ask someone that has a GP20 tho to be 100% sure?
If your GP 20 has a DCC ready board you may get lucky by just having to pull the black clips off and pulling the wires out of the board. this would make life easy as no soldering wil lbe needed. If you have ever taken apart an old 4 axel Athearn you will find the 4 axel protos are exactly the same. only diffrence is the protos have the weight over the frame/motor.
I replaced all 4 axles with no improvement. I used an NMRA wheel gauge as well. It still screams. The fuel tank cover has no screw or any obvious way to remove it that I can see. It moves a bit on one end , but is very secure on the other end. It does not budge!! VERY FRUSTRATING!
I've already installed a DCC decoder that works fine. If I could only get to the inards, I'm not intimidated to pull it apart.
For what it's worth, I about broke my fingers off but got the fuel tank cover off. It was held on by old double stick tape. Now to find the problem. It seems to be confined to the front end drive area. Any ideas?
It would be good to remove the whole truck. With it removed and it still assembled, you can turn the worm gear (input from the motor) with you fingers and feel if anything is binding or catching. Then disassmble, clean up, then look everything over good. Check each gear for anything wrong, like something jambed between teeth or stripped teeth.
