Weaver GP-38 2 will not move

It may be the drive shaft which split and slip on older Weaver. WEAVER did supply the parts. There is someone on the forum that has those parts.

Also, check the grease in the trucks as they may have picked up ballast or debris.

Parts are available from P&D hobby shop.

Measure the diameter of the splines on the shaft after you clean all the plastic debris out.  Im pretty sure its this part. https://pdhobbyshop.com/produc...mall-helmut-shafts-2

Replacing the spider is also probably a good idea. https://pdhobbyshop.com/produc...er-universal-joint-4

That will reconnect it without it slipping, but the gears are a known problem as they age over time and can split.  You can get all the parts to totally re-hab it, but the U joint will get you reconnected for now.

P&D Hobby has the parts as stated.

Here's are the diagrams:

Have these parts been improved over the originals?

Darrell,

Thanks for the part diagrams.

In #2, I ordered the 10008 shaft and the 5297 sprocket and the 10002 and 10007

The sprocket that is on the original engine was larger (blue and with 12 teeth) than the 5297 (white with 8 teeth)

The original one matches the lower gear size.

the new sprocket is not splined so do I press that on to the shaft?

Is the small gear going to give me an issue with the chain?

Any advice?

Thanks again

Sounds like you got the sprocket for the low gearing upgrade. If I remember it presses on the shaft, its been a while since I installed one, and I only did the gearing upgrade to one of 3 that I own. P&D sells a longer chain as well for that upgrade, either way the chain will have to be adjusted. They have a dummy to power kit I used on the last one I did and it had an adjustable tower to dial in the chain.

Just check the website and not finding the kit or adjustable tower anymore, bummer.

P&D has a lower gear - 10:1  Do you know if that was the upgraded gear and would it fit

Should be a direct replacement.

I would personally stick with the 8-tooth gear, which combined with the 12-tooth lower gear and 10:1 gearbox will give you 15:1 overall.  This will give your diesel smooth slow-speed operation and a prototypical top speed, i.e., slower than most of the toy trains that have been made in the last 80 years.

Individual half-links can be removed from the nylon chain to take up the slack.  If you break the chain, look at it closely under a magnifying loupe, or feel it with your fingers.  There are mold release burrs on one side.  When you reinstall it, make sure the burrs are on the outside, or it will run roughly with excess friction.

There are other posts on this Forum and elsewhere on the internet that offer tips on tuning the Weaver / P&D drive.  Good luck!