85 GL Wagon ("Jill" as my daughter call her). All 4 seat belts seem to not lockup when pulled. Is there something electrical I should look at or are they all purely mechanical. They do lock up if jerked very very abruptly, but other belts I've seen lock with alot less effort. 

 

I don't want her to "bump her crown" on the steering wheel if she gets into an accident. 

No electrics involved, purely mechanical. And older cars seat belts do tend to require quite an abrupt tug to trigger the "lockup". If you are really concerned, you can buy aftermarket (NOT eBay) retracting belt sets online, but be forewarned they do cost a bit.

In mine they don't lock up when pulled, either. Looking at them, there's a ball in the mechanism that I think moves forward in a crash causing the mechanism to lock.

If I'm parked on a really steep hill, or sideways, the seatbelts won't pull out until I'm on flatter ground.