Service Pack 1617000430

The kit comes with a parts diagram but NO instructions! They list all the parts online, so you can get the names from the site. The diagram has the parts in the kit in bold, so at least you know which to replace.

The striker was frozen in the hammer pipe, and freeing it took a lot of prying and tapping. That may have been all that was wrong, but I purchased the kit, so I used it all. Removing the striker was the trickiest part: there is a split ring at the base the striker that can just barely be seen through the holes in the pipe. You have to pry that down and off just working through the holes, and that was crazy hard. A lot of it may have been that I wasn't even sure it came off. The rest is just very carefully minding the parts. It can help to use a small clamp to hold the two stopping device parts in place while juggling the whole thing back in place. A lot of grief, but the tool works like new now.

1. Remove bottom plastic cover with allen wrench
2. Remove power cord(optional)
3. Remove nose piece assembly
4. Remove secondary handle
5. Remove top lid via. 6 T25 torx screws. Note: Machine thread
6. Drain oil
7. Place in vice holding on to neck right where secondary handle mounts
8. Looking into nose area with snap ring pliers remove retaining ring, large keyed washer, and
large metal collar
9. Now standing in front of and looking down at the spot that you removed the lid rotate
piston so where it connects to the gear is either farthest or closest to you and use a flat
screw driver to gentle wedge the arm off the dowel that connects it to the gear and
pull out entire piston assembly
10. Now this next step your going to have to PAY ATTENTION, slide the barrel out thru the
Nose and place to the side. Back where the piston "was" at the very front of that pocket
there is a assemble that includes a gear sleeve, usually two shims, an outer sleeve,
and an inner sleeve. Don't scratch, bend, tweak, or mar these shims in anyway.
11. Now for the last piece, inside the nose body after everything is removed, look and you
will see an O-ring right in the middle, its no wider than 1/16th or 5/64ths of an inch.
Remove it.
12. Now inside the barrel there is a retaining ring, use a very small flat head screwdriver
from the outside thru one of those little holes and pry up just enough so as to pop it
out of the groove it is in. Now from the inside of the barrel use one of your looong looks, the one that looks like it was from captain hooks missing hand, and stick it down the
inside of the barrel and hook that ring, now gently wiggle that ring so it is perpendicular
to original position and yank with one hard pull and it should come right out of the barrel
Tap the upright barrel lightly on your work bench and the three other pieces should come falling out.
13. Now remove roto from vice and clean in side mechanical compartment with break cleaner. If you use a water based cleaner make sure to dry it out completely, like take an air
compressor to it when you think you got it all out. Also clean each part that you removed
as well
14. Now do these steps backwards up until step two.
15. Remove brushes one at a time. Note one brush has two wires, this is why I say one at a
time.
16 . Now just finish the assembly and don't forget to add your oil res. before running.

Bosch Model 11241evs - This is a very well designed tool. Not a big Bosch fan but this tool is worth fixing.

Lots of good advice here already. Take good pictures along the way, you won't regret it. It's easy enough that I was glad I didn't pay the Bosch factory $340 + Shipping.
The little internal snap ring that holds one of the strikers inside the tube - likely the part that's bad to remove. As one user explained, you have to work it through the holes in the side of the tube. It's a puzzle and you'll need a little patience. Everything else is straight forward - seals, etc. It's a little like working on an automatic transmission.

Follow diagrams for tear down. Clean everything and install new seals. Reassemble.

I have a Bosch model 11241evs Rotary Hammer. Gun only has 20- 25 hrs on it. was able to get into the hammer end of it with out taking motor apart. Brushes looked like new anyway. The striker [no 57] was stuck in the barrel, out of reach of the piston. And the breakdown from eReplacement does not show the striker pin [ no841] in their breakdown. Went to toolparts Pro for a correct detail of the gun. It was a time consuming tear down. ,Getting the snap ring out from the inside of the barrel was a challenge with that striker stuck in there. You need a lot of patience.

Opened unit put prong on piston added oil added other o rings and gaskets
Put unit back together and it still won’t work so I scraped it and bought a new one
Would cost more than it’s worth
Already spent money on the repair kit

I installed The service pack on a Bosch 11241 esv Demo hammer drill my advice is to take your time take step-by-step pictures during disassembly for reassembly and stack all removed parts in order this is a very complicated job but you can do it yourself and save $300 of shop cost

opened the housing broke it down cleaned all the grease out ( fresh start) replaced gasket, removed and replaced the housing for the brushes, sanded down the copper to a bright shine
replaced the brushes .
put all new grease on components, and re assembled.
Hardest part is removing the function switch . push the red selector button all the way in turn clockwise past the hammer, and use a flathead to pop it off.

be careful with the brush housing its plastic tabs can break easy housing its a pressure clip

1. Disassembled, referencing exploded view from repair kit.
2. Cleaned all components.
3. Replaced components included in service kit.
4. Re-assembled unit referencing exploded view and using plenty of oil for gearbox components and grease for chuck components.
...the repair is more simple than the number of components implies. I recommend buying the Bosch oil as I got lucky to find equivalent oil at work, otherwise I would have probably compromised for something local and sub-par.

Removed the top oil cover, drained the oil, washed out with solvent, changed the O rings, reassembled, works like new!