Janome memory craft wont go forward

Hello, Sauban -

The needles you will use will depend upon the kind of sewing you will be doing and the fabric on which you are sewing.

The Instruction Manual for the Janome Memory Craft 6000 lists the needle sizes on page 22 of the manual:
https://www.janome.com/siteassets/support/manuals/retired/computer/inst-book-mc6000-en-new.pdf

The website SewingParts Online sells a variety of needles for use with the Janome Memory Craft 6000:
(TinyURL link): https://tinyurl.com/yb3oy2wo
The company is located in the USA.

If you do not reside in the USA, then, I suggest you use your favorite search engine (Google, Bing, Yahoo, DuckDuckGo, etc.) and the following search phrase, with quotation marks as shown to find needles for your machine from a business in your country of residence:
Janome "Memory Craft 6000" needles

Best wishes.

Is it a Janome brand walking foot? some generic feet and other brands don't fit the older Janomes.

try contacting janome customer service
1-800-631-0183, ext. 774

I would suggest to get another option, those motherboards are
expensive

Switch broken, have it replaced

If you pull the bottom off the machine (half a dozen screws) there is a cam on the main drive shaft. The cam is probably jammed in the reverse position due to lack of lubrication on the shaft. You can move the cam back manually and it will operate in forward direction. It appears that the shaft needs lubrication.

You are threading the top of the machine incorrectly.

Make sure the needle is in correctly with the flat side to the rear of the machine, make sure to thread the upper and lower portions of the machine correctly. If this does not solve your problem, please respond.

I have a Janome 9000, was sewing and broke needle, replaced and broke another. I didn't have machine threaded, took out bobbin and would sew a little and stop saying thread broke. I took off top plate and started machine again, sew a little and stop saying thread broke. So I took out bobbin case and sewed again and stopped repeating the message. Everything looks OK, bobbin case and top plate. I guess I want to know if the timing could be off or do you think it is the computer part of the machine...Should I take it to the Sewing Machine Shop??

its the sensor on the bobinwinder who are loose. If you are handy. you can remove the top cover of the machine.
And on the left side of the bobinwinder you will find a micro switch. Probably you have to tighten the screw on it..

Here is the Manual