Haynes / Cylmer Discrepency - Klassic 2 Valve K's
While looking at both manuals today for torque of the oil drain plug, the Haynes states 32 Nm whereas the Clymers says 20 Nm. That's quite a difference. One must be incorrect. Does anyone know the correct torque for the oil drain bolt? :scratch
As well, are they other inaccurate torque values in either manual? :dunno
Safe side: Don't overtighten
The #1 problem with drain plugs in any form of vehicle is people tend to overtighten. Nobody want his/hers to fall out our leak!
However, there is a stiff price to pay if repeated over-tightening takes place: stripping the threads!
Also, NOT draining through the drain plug hole prevents you from cleaning off the magnet that is on most of them embedded in the plug.
Often, specs from manufacturer are usually on their best interest safe side which is to make sure that it can't come out, so their specs may be really to tight for long term usage.
The best is to have it just tight enough that it won't leak, or back out from vibration or something else, but not tight enough to do any damage to threads.
Go with lightest torque,l and then CHECK it REGULARLY to make sure it hasn't changed! Get the best of both world.