How to remove chuck on porter-cable model 978 drill

I just looked at some illustrations on ebay of Porter-cable 18 volt drills and they appear to be fairly standard cordless drill/drivers fitted with fairly standard keyless chucks that you get hold of with both hands and twist in opposite directions like you are giving it a Chinese burn. The part of the chuck nearest the bit twists anti-clockwise to loosen.

If you have an SDS drill for heavier duty jobs the chuck is semi-automatic in the drill bit just needs pushing into the chuck and clicks into place but the outer part of the chuck is pulled back in order to release the bit.

Switch drill to reverse, grab drill head tight, do not grab bit, pull trigger, chuck will open, switch to forward center new bit hold head tight pull trigger. Make sure bit stays in center, Let me know if this helps.

there should be a allen head screw that holds the chuck to the drill shaft should be a easy fix put loc-tite on screw threads before reattaching screw and chuck and tighten up screw

go to the tip section and I put detailed instructions there, or under my profile it is there also. Let me know if still having problems

if you are talking about the J621 3/8 Professional drill the chuck kit number is 692074 and it lists for 43.30. You can but that from Dewaltservicenet.com or if you need more assistance let me know.

Grab the chuck with a pair of water pump pliers, and crank it in reverse. Hang on tight. Spray some wd 40 in the chuck before you get it spinning again.

see my post in the tips and tricks section for chuck removal.

open the chuck all of the way, look down inside

you should see a screw down in there

it is REVERSE thread

lock the chuck in a vise and remove the screw

It sounds like you were between gears. When you are in neither low or high, you are sort of in neutral. Normally it isn't a big deal. It happens to me occasionally, and I do what you did. You should be OK.

Most chucks have a tolerance the cordless drills where designed for drill bits 1/8 and larger the 3/8 chucks are a little better with the smaller bits .Check your owners manual and see if they have a min requirement listed for the bit size