Ks656pe how do i change the blade? i don't have any instruction. Please

It's likely the tension nut or screw needs to be tightened a little more providing the drive block is in place and the blades have been put on correctly.

You shouldn't need to buy new blades even when they go blunt just send them to a professional sharpener

Don't forget that the bolt that holds the blade against the arbor (the motor hub connection point) is threaded COUNTER-CLOCKWISE. This is the opposite of nearly everything else we encounter. Be sure to use the two wrenches you got with the saw, and like the directions always say, "Unplug unit before servicing!"

Your blades are either damaged and locking up or they are so clogged with hair that they can not turn.
I suggest that you try to clean them first. If that doesn't work you will need to change them. You will find replacements for model HQ4806 at shaveroutlet.com. See link below for product and disassembly instruction video

http://shaveroutlet.com/shaver-replacement-parts/norelco-philips-hq56-super-lift-and-cut-replacement-heads-p-249.html

Please consult the online manual for your saw here, and review this article about changing the blade.
All I can say is, You're not the only one, Thank God they finally changed the design of the blade change mechanism, How could it have taken that long for a bunch of German engineers to figure that one out, and you have my sympathy for owning one of those that use neither a screwdriver nor the new quick release mechanism.
Realise to begin with that the blade goes in and slips out in a position about 45 - 90 degrees away from the position it's in when cutting. In other words, the teeth must be turned somewhat to the side of the saw to allow the blade to slip free. Before that can happen, however, you must use that ridiculous handle mechanism to loosen the lock screw that holds the blade in place. First set the orbital selection switch to III or max orbit position. This will give you a little more flex when pulling the blade free. You might also pull the blade out to a more downward position if it's up inside the saw quite a bit. Pull up on the handle as shown in the instructions and rotate counterclockwise (looking down at the top of the saw) to loosen the blade, being careful not to pull up on the handle too much when it is exactly 180 degrees from the home position, or it will come off in your hand. That is the position to reinsert it in when it comes off, then turn it a little to the side to pull up again. I don't have much use for the push upward and pull downwards advice they give, regarding the tabs on the blade itself. It seems to me they could have figured out a way to keep the handle on the saw while you pull up on it to loosen and tighten the blade in place, but I guess with patience you can get it back in and tightened up again.turning what should be a thirty second blade change into a frustrating ordeal. The older model used a special long shank flat head screwdrive, which worked fine, but everyone would lose the screwdriver or forget to bring it to the jobsite, and without it you couldn't change the blade in that one either. Once you get the blade in they work great!
Anyway, know you're not alone when you curse Bosch, and someday you can replace that little pain for an upgraded model that has a 3 point support mechanism and much better blade change mechanism, or you could go all out and buy a Festo jigsaw, that you would love for the rest of your days...
Sorry for the rant. I hope that helps. I see that you wrote about a month ago, so hopefully you managed to cut your wood by now.

I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
If I've managed to answer your question or solve a problem, please take just a moment to rate this post....thanks!

Sorry Gavin, but you have posted this solution word for word the same for a number of jigsaws. the KS656PE does not have a knob to pull or turn so you do not know this model and your suggestion is wrong.
I cannot advise a correct solution as the advice in the manual is wrong!
regards - Mark

The model in your picture is a fixed blade utility knife (model 10-816). Your question asks for instructions for model 10-778, which is a retractable knife. I'll guide you through the 10-778 which you asked for, if you need instructions for the pictured 10-816 please re-post the question.

Push the thumb slide forward as far as it goes exposing the blade. Press the blade change button on the side of the knife (the small button on the left side near the blade) and pull out the old blade.
Insert the new blade and slide thumb slide back to fully engage blade in the internal lock.

UNPLUG TOOL. To remove the blade, lift the knob on the top of the jig saw approximately 1/4".

Rotate the knob counterclockwise until the clamp is open (Figure 8a). Do not force the knob once

it stops. Insert the blade as shown. Make sure the back edge of the blade fits into the support roller.

Tighten clamp by turning top knob clockwise until you hear a click. Push knob down.
For "T" shank blades, insert blade to the shoulder of the shank.

Look at manual on the link below.

http://www.dewaltservicenet.com/documents/English/Instruction%20Manual/402086-01,DW321.pdf

Good luck please rate 4 thumbs up and please leave a testimonial

The gold looking circle on the side of the utility knife. Just unscrew that and it will pop open then you can change the blade. I looked everywhere and am unable to find the instruction or picture. I own one and that is why I am answering this for you. Please rate

Here is the owners manual for your saw. It details the procedure for removing and installing a blade.

Please rate this positive if it helps!

http://www.dewaltservicenet.com/documents/English/Instruction%20Manual/Porter-Cable/En900003.pdf

Here is a link to the instruction manual, and just under the place where it says Save These Instructions it tells you how to change the blade.
http://www.dewaltservicenet.com/documents/English/Instruction%20Manual/90520882,JS515.pdf
Fitting the saw blade (figure A)
- Hold the saw blade (9) as shown, with teeth facing forward.
- Push the lever (3) downwards.
- Insert the shank of the saw blade into the blade holder (10) as far as it will go.
- Release the lever.

There is a little lever where the base of the blade fits into the holder that you depress to release the blade...You can see a picture of it in the manual.

I hope this answers your question...if so, please take a aec to rate this post...thanks.