Looking for info on how to separate the motor from the truck. Need the truck have to be removed from the chassis? Removed a few of the accessible screws but without the wanted results.
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What model Atlas engine is it? On the RS1 there is a small screw on the top of the truck up against the motor. Even with a long, thin screwdriver it is awful to get out.
Ken
I just went through the same issue.
There is a screw underneath the truck that holds the motor to the truck (that can be removed first, it is easily accessed and identified).
On a GP9's and Erie-Built FM's you need to remove the truck from the frame (4-screws). They hold the chassis insulator and bolster plate. The main reason to remove them is to get to the two screws mentioned next.
Lastly, there are two screws on the top of the truck. I'm sorry I don't remember exactly what their purpose is, but when those to screws are removed, there is some gearing called the power gear transfer assembly, which will loosen allowing the motor to be separated from the truck.
As Mike posted, print a copy of the parts diagram(s). They will help, although leave a little to be desired.
Most vertical drive motors are removed by a single screw coming in from the bottom. It is recessed and easily identifiable.
Not so Atlas - there is an additional screw holding a "tongue" of sorts to the truck block, and the electrical pickup might be involved as well.
Getting it apart is not your major problem. Getting parts, and getting it back together, are the challenges. There are a pair of bearings on the worm gear shafts with small flat spots. These flat spots must be placed back in the truck block in the proper orientation - not a trivial task. There also may be a small washer down in the bottom that fits the worm shaft. Use care that the tip of the worm shaft slips into that washer. Obviously, that too is not trivial.
Atlas, in my opinion, would do well to copy MTH or K-Line. We currently have a "down" Atlas Diesel - inoperable because we cannot get parts.
Guys, it is a GP7/9. Mike I did look at the diagram before I posted but it does not show the fasteners that actually hold the motor in. The body is off and removed the obvious phillip screw from the bottom of the truck. As Howard says, I will have to go to the next level and remove the truck and motor assembly from the chassis to finish the motor removal. I have had a GP modified to a "chopped nose" Geep and fitting the body necessitates the motor removal from the truck for clearance of the hood.
Thanks for your help!
Bob,
I must have been composing my previous reply when you posted your response. I'll be sure to look for those "trivial" parts in the disassembly but as I stated in my first reply, the motor is not going back in. The truck will be an idler.
cape cod: bob2 above has the details correct. I've had all my Atlas diesels stripped-down to re-lube this Spring. The two screws atop the "tongue' the motor mounts to need to be removed. One will hold the roller collector assembly and the other screw mounts a ground screw to the truck. Once you have them out, the motor mount lifts of the top.
As bob2 alluded to, there is a brass thrust washer assembly (for the worm) with a square tang around its perimeter that locates it in the bottom of the truck block. It needs to be seated correctly along with the "flat-spotted" axle bushings upon re-assembly. Be sure everything rotates freely upon re-assembly; if not, one of those bushings is not seated correctly.
It took some time but the operation was a success. The front truck did have to be removed from the chassis but to do that, the motherboard had to be unbolted so that it could be shifted sideways to gain access to the rear screws holding the truck plates on. Both the screws holding the pickup roller and ground wire had to come off also. Once the truck is out, and the plates (2) removed, you now have access to the two scress that hold the motor to the truck. Remove those and the motor is released. Then the reassembly began and went pretty smoothly.
Testing the chassis and one motor operation, I did obviously find a loss of pulling power. Pulling 9 Atlas Master freight cars around my level tracks were fine. Assaulting my 2% grade saw the engine stall with wheels slipping. Five cars were the max without any slippage. EOB worked fine with just the one motor. MUing with another Atlas engine worked fine also.
Al, any pics? Yes! It can be done!
We could use spare motors out here. We could pay, or issue you a tax deduction certificate. The latest Atlas casualty has both motors with worn out front (bottom) bearings, among other things.
I am advising them to go MTH henceforth.
Sorry Bob, it goes into my parts bin for future projects.
Bob,
When Atlas came out with their unpowered GP9s I bought one. Shortly after I realized I didn't need or want an unpowered engine.
Not too long after that I won a Railking F3 on ebay for $105. Found it was too short and then got the idea to see if the PS2 guts and motors would fit the Atlas GP9.
Worked like a charm, I ended up with a powered, command controlled, Atlas engine for around $300.
I did have to buy the transfer gear assembly from Atlas but that was all.
Other than the work involved in getting to the motors, it's worth a try.
