I need the instructions for adjusting the drive chains on a GMC planer thicknesser

Yes for $5.00!

Copy of Manual for SCM S520 Thicknesser - Scott+Sargeant

Scott+Sargeant https://www.scosarg.com > copy-of-manual-for-scm-s...

Buy the Copy of Manual for SCM S520 Thicknesser from Scott+Sargeant with fast UK and global delivery, finance and service packages.
£5.00

Copy of Manual for SCM S520 E

Scott+Sargeant https://www.scosarg.com > copy-of-manual-for-scm-s...
Downloadable Copy of Manual for SCM S520 E this product is downloadable only. Next Day Courier for Stock items up to 30kg; Crane + Pallet Delivery ...
£5.00

Thicknessing Planer Class S 630 - Class S 520

Scm Group https://www.scmgroup.com > ... > Thicknessing planers
Class S 630 - Class S 520 is the best solution to every application. Easy and precise, practical design, a wider range of applications.

..

Are you in South Africa? It doesn't seem to be a known model in North America where we are. This link might work better for you.

https://www.google.com/search?q=Ryobi+JT200+parts

and also

https://www.google.com/search?q=Ryobi+JT200+belt&rlz=1C1QJDB_enCA643CA644&sxsrf=APq-WBtBERd3qAMszYcAMMHfwL-snySOGQ:1643739137693&source=lnms&tbm=isch&sa=X&ved=2ahUKEwia2J67jd_1AhUplIkEHZH4A1EQ_AUoAnoECAEQBA&biw=1920&bih=937&dpr=1

..

Portable thicknesser has all the powered parts in the power planer head including the powered rollers that auto feed the timber under the planer head.
I have never had one apart so I don't know how the rollers are connected to the motor though as the head is so compact it is more likely gears than belt (mine is floor standing and uses a belt) and likely has some sort of overload clutch that will slip in case of an overload.

Whatever the drive system is, it clearly needs repair and that will mean removing and dismantling the power head and when the faulty component is found it might be a good idea to order two to cover future replacements.

I couldn't find an illustration of the planer so don't know whether it is a compact bench jointer, a portable thicknesser or a workshop planer/thicknesser where any suitable motor can easily be adapted to fit, often representing large savings over the machine manufacturer's prices.

Replacement motors and motor parts for integrated machinery often become obsolete quickly or are available but are priced not to sell and an otherwise good machine has to be replaced.

There are many companies around the world offering small motor rewinds, usually at prices far less than a replacement motor, offering the chance to make an otherwise obsolete tool useful again.

Part # 827794 Chain
They sure do look like bicycle chains, but without measuring the links with a micrometer and comparing them with a bicycle chain, i wouldn't be comfortable installing one you made based off of eyeballing it alone. You may know this already, but be sure to remove both sprockets the certain chain rides on, and assembling the 3 pieces as one assembly back on the shafts, its much easier then loosening the shafts from the main unit.

Try at eReplacementParts.com : Power Tool Parts and Tool Repair Diagrams.

If you need more help come back.Post / thumbs / testimonial are welcome!

www.machines4wood.com

I Also have a BAO 12 and im trying to find out about the starter as i need a new one. But the company above have a copy which i am ordering. His name is Ben Thatcher.

Hope this helps Rob

Here is a site:

http://www.localaccess.com/1942/ryobi/ap12.html

Find the AP13 belt there... wow...$30... ouch!