How do I remove the universal yoke from gear box on a john deere 640 hay rake it that yoke threaded on, if so what thread ccw or cw?

https://pdfgoal.com/downloads/John%20Deere%20Engine%20Fault%20Codes%20Spn%20Fmi%20File%20Type%20Pdf -------https://www.heavyequipmentforums.com/threads/john-deere-310sg-code-problem.40049/ ---------------https://www.justanswer.com/heavy-equipment/2vsmv-hello-getting-fault-code-f495-john-deere-backhoe.html -----------https://www.heavyequipmentforums.com/threads/trouble-codes-jd-h-series-dozers.6308/

normal thread.
CCW off
CW on

plug threads come in 3 different sizes
check your new plug against the old plug and check thread dia and length
if it is not the same , the plug selection is wrong
the other problem is
if the original plug was too long the carbon would be in the thread and on removing the plug , the thread in the head would have been destroyed as well
in that case you will need a plug thread inset installed before any plug will fit

Try manualsonline.com or manufacturer

There is a left handed thread and a right handed thread on the arbors.

Removal
Right Hand Side (RH)
Wrap a piece of rubber or leather around the threads on the LH side of the arbor & hold with pliers, while turning the RH nut CCW.

Left Hand Side (LH)
Wrap a piece of rubber or leather around the threads on the RH side of the arbor & hold with pliers, while turning the LH nut CW.

Installation
Note: Hand tighten the nut, then 1/4 turn.
Right Hand Side (RH)
Wrap a piece of rubber or leather around the threads on the LH side of the arbor & hold with pliers, while turning the RH nut CW.

Left Hand Side (LH)
Wrap a piece of rubber or leather around the threads on the RH side of the arbor & hold with pliers, while turning the LH nut CWW.

For grinding stones:

• ring test the stone
• discard the stone if it has been dropped
• be sure the paper washers are installed on the wheel

GRINDER SAFETY 101 (graphic injury video so be warned)

http://www.garagejournal.com/forum/showthread.php?t=263083

There is a left handed thread and a right handed thread on the arbors.

Removal
Right Hand Side (RH)
Wrap a piece of rubber or leather around the threads on the LH side of the arbor & hold with pliers, while turning the RH nut CCW.

Left Hand Side (LH)
Wrap a piece of rubber or leather around the threads on the RH side of the arbor & hold with pliers, while turning the LH nut CW.

Installation
Note: Hand tighten the nut, then 1/4 turn.
Right Hand Side (RH)
Wrap a piece of rubber or leather around the threads on the LH side of the arbor & hold with pliers, while turning the RH nut CW.

Left Hand Side (LH)
Wrap a piece of rubber or leather around the threads on the RH side of the arbor & hold with pliers, while turning the LH nut CWW.

For grinding stones:

• ring test the stone
• discard the stone if it has been dropped
• be sure the paper washers are installed on the wheel

GRINDER SAFETY 101 (graphic injury video so be warned)
http://www.garagejournal.com/forum/showthread.php?t=263083

fan clutches are Left hand thread as they tighten up when the engine is running. If they were right hand thread then when the fan is working they would come loose off the shaft
In short undoing then actually tightens them

Hi edward, looks like you posted the same question twice. I already answered the other one. good luck.