removing glass in one pieces

[stayclean]

ive been ask to reseal some sealed units in wooden frames , glass has been fitted for over 12 years now , its seem windows have started to left draft in and water around glass, plus on openers there is a type of seal which has perished which is attach to frame this also need changing . i intend trying to remove glass and reseal with glazing foam to try and stop draft and water,
can i use a type of seal like a single sided glazing foam to seal openers when there are closed

 

[joe-90]

Don't like your chances of getting them out in one piece. The slightest leverage with a pry bar will crack them.

 

[stayclean]

Don't like your chances of getting them out in one piece. The slightest leverage with a pry bar will crack them.

i will remove wooded beading around 3 units i dont need to change and see if i can reseal them without removing glass , it seem windows catch all the wind and rain so hopefully i can reseal them