removal of worm and wheel gears

[controller]

Hi, I have a Hornby shunter 0-6-0 loco which is running very bad. I have replaced the motor, but I think the problem is with the worm and wheel gears. I have new ones on the way. Can you lads tell me how to remove the old plastic ones. The new replacement worm and wheel gear are brass. Do I need to secure these with some sort of glue.

Thanks,

Controller.

[Mayner]

 Buying a replacement chassis on trade me may be a safer option than trying to replace the gears. https://www.ebay.co.uk/itm/Hornby-R353-0-6-0-chassis-motor-with-LBSC-tank-loco-brown-wheels-OO-Gauge-/372247948958

The trickiest part of the re-assembly is making sure that cranks are in the right position relative to the other wheel sets (quartering) when you re-assemble the wheels on the axle with the worm gear, otherwise the loco will not run or run very badly.

If you want to give it a go special tools are available for removing wheels and gears from axles https://www.google.co.nz/search?q=model+railway+gear+puller&rlz=1C1CHBF_enNZ752NZ752&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwih-OCd_IHaAhUJvLwKHSihAlAQsAQIKQ&biw=1920&bih=974.

Loctite 601 retainer is the best option for securing a gear or a worm on a shaft or an axle, great stuff but don't let it near a bearing or it will lock the shaft solid.

John

[David Holman]

Just to add to what John says, you may find the worm and gear come with grub screws to hold them to the motor/axle.

 However, wheel quartering is not for the faint hearted and get it wrong will only make for even worse running.

[controller]

Thanks Lads, Managed to get the old parts off, waiting for delivery of new ones, then comes the fun part. Will let you know how I get on. 

Controller.