Log in

View Full Version : Rebuilding bosch demolition hammer - Need help


KISS
May 9, 2010, 10:17 PM
Rebulding a 11316evs demolition hammer.

Parts diagram is here: Bosch 11316EVS Parts List and Diagram - (0611316739) : eReplacementParts.com (http://www.ereplacementparts.com/bosch-11316evs-0611316739-demolition-hammer-parts-c-128_1391_3183.html)

I got all the parts replaced in the drive system, but having trouble figuring out the chuck. The chuck starts at 18 and ends at 21 on the diagram.

18, 39, 18, 138 are removed. 21 and 22 are removed.

31 is a rubber bushing and it looks like I need to compress from 144 on down, which is about 7" of stuff.

143 isn't a snap ring. It's just a totally round ring with a 1/8" gap.

I can't figure out how to do that.

I briefly tried a hand clamp, a 1-3/8 open end wrench and a hole saw and a block of wood on the other end. I can't get enough leverage with my clamp.

Any ideas?

I have two:

1) Pipe clamp
2) or see if local service center can help

Then I'm not sure how to put it all back together. I might have troble installing the new clip.

I do believe that I have to get the ring off.

FYI: 138 is an internal "O ring". 39 is a seal. And the 18's which are c-clips keeps the seal from moving. I d believe I can install these.

hkstroud
May 10, 2010, 04:43 AM
KISS
Am I correct in assuming that the problem is compressing 144 through 19 so that retaining ring 143 can be removed?

KISS
May 10, 2010, 07:53 AM
That's an idea. One base can be solid. Plywood might bend too much. Your right, that's a basic press.

KISS
May 10, 2010, 02:57 PM
I punted for now.

Dropped the chuck off to a rental place. $30 for 1/2 hour minimum labor charge. It should not take them longer than that. They were 1.5 miles away.

Same chain has an authorized repair center about 13 miles away.

I stopped in another authorized (small appliances) repair center. I never liked their additude and they have a $45 minimum charge, so I'll probably do OK.

Meanwhile I flagged down a tool truck and picked up a 10 mm angle hex bit, 3/8 drive. I should be able to turn it around and use it in straight mode. I have to torque something on the hammer.

KISS
May 12, 2010, 02:00 AM
I think I know what I would do if I wanted to do it myself.
Maybe a 2x4 on the bottom with two threaded rods like you suggested.

And probably a 1/4" steel plate that is hole saw drilled in the center and the one side cut out in the shape of a "U" which is typical of a press except the "U" thing is probably about 3/4" of an inch.

hkstroud
May 12, 2010, 08:12 AM
I guess it depend on how strong that spring is. I didn't look that closely to see how big the demo hammer is. I can see the U slot for convince of slipping the plate on the shaft.
Don't understand the angled hex bit unless you mean a 10mm Allen wrench.

If the spring is so strong as to require a steel plate, be careful, never like messing with compressed springs. Wouldn't want to have to hole saw 1/4" steel.

KISS
May 12, 2010, 12:36 PM
The chuck assembly is about 7" long.

It's not the spring that's strong. The spring requires very little pressure. It's compressed to change the bit. It's a rubber bushing that needs to be compressed.

I made a plate to press in a bearing when I had access to a 3 ton press and a machine shop. I may have fly cut it with a mill which would have been easy.

10 mm Allen = 10 mm Hex (3/8 Socket drive)

KISS
May 13, 2010, 03:16 PM
So, now they tell me. No need to use a press. They said it took about 10 minutes, most of it cleaning the old parts up.

So, I'm almost done.

KISS
May 13, 2010, 07:31 PM
When I went to put it back together, one of the "O-rings" is missing. The good one. The other one is chewed.

I hope I can find one locally. If I order, $.05 ea, $5.00 minimum or I can order from a tool distributer for $4.13 each, 2 week delivery.