Will I loose a lot of oil by not draining it? Or should I just drain and refill? New plugs also while in there.
The last time I briefly read up on this job, it sounded like you would not lose a lot of oil. I would probably let it drain for a long time before pulling the covers just to avoid a mess, but I'll let others who have actually done this job chime in.
There wasn't much when I did mine and for sure do the plugs if they are even close to doing. Also be careful torquing the bolts. You don't want to be in a helicoil situation. I followed the book and only put the liquid gasket on the spots specified. Others said do the whole gasket.
You will loose about 1/4 of a quart if that, yes of plugs at the same time you are there might as well.