pushing on dog-gear, 915 rebuiliding?

BrokeMyCar · 11-13-2011, 12:54 PM

Hi folks,

I'm trying to push on a new dog-gear onto 1st in my recently disassembled 915, and I can't seem to get it on straight. I've tried a few approaches, using a C-clamp, or a gear puller (image shown here), using the P226 too so I can handle it better, and some propane heat. I'm wary, given Zimmerman's advice that slight cocking will break the ring.

Any suggestions for approaches to try? Is a little cocking during installation ok, or should I immediately back out (as I have been)?

Thank you,

Babak

TimT · 11-13-2011, 01:21 PM

Are you heating it? or trying to put it on cold?

john walker's workshop · 11-13-2011, 01:22 PM

they're swaged after installation by the factory, so that swage is still there after removing the original teeth. that's what makes it hard to get the new one on. i dress the swage a bit with a file. don't remove it entirely. a 36mm socket on top and a press works wonders. never tried it with stone knives and bearskins.

BrokeMyCar · 11-13-2011, 01:33 PM

I thought I was all homo-habilis with the P226 tool - but you're right, without a press I'm really back in the Bronze age =).

I was heating it while in the P226 tool and then pushing it on. Off to the hardware store to buy some files, thanks for the tip!

While I have you guys here, on an unrelated note, do you see anything wrong with shaving off the flange of a new DEC catalytic converter? Its diameter is 2 mm too big for even the gasket, so I was thinking of grinding the whole lip off.

Thanks!

Babak

PS yes, I just hijacked my own thread. Lots going on in this little garage.

cgarr · cgarr's Garage

I never had any luck with heat. Those notches have to all line up and if you heat it the ring is larger and the notches will not line up.

BrokeMyCar · 11-13-2011, 03:15 PM

I did a little shaving, and tried a little more heat - it's going on easier, but still cockeyed. Should I be shaving more? Should I keep pushing even though it's cockeyed?

cgarr · cgarr's Garage

It has to be straight! Thats the key to getting these on, once its straight it will press right on.

DSPTurtle · 11-13-2011, 04:25 PM

Move your cP over to the top a little (in your photo) and keep pressing. It will straighten out. Unless you are using a really big press, you are gonna have a hard time breaking anything.
I have done this job with hammers, a vice and a hydraulic press. The press is easiest but they all can work. Grab your balls and crank that b!@tch... YMMV

Matt Monson · 11-14-2011, 08:43 AM

You need a press. The way you are trying to do it won't get it on there properly. If you keep screwing about the way you currently are, you are going to compress the inner bore of the gear and have to hone it after you get the dog on. You need to be sure to check the hone regardless once you get it on.

Regards,

Matt

Quicksilver · 11-14-2011, 12:29 PM

There are two sides to heat... Freeze the other side. An hour in the freezer might do the trick.
Also check the side that is still up. Maybe the swaging is still a bit proud there.

Quote:

Originally Posted by john walker's workshop

. . .
never tried it with stone knives and bearskins.

Thanks, I needed that. Funniest thing I've heard all day.

arbita1 · arbita1's Garage

I put my gear in the freezer. Maybe over night, but at least an hour or two I think. Then I used a vice to press them together. It might be that clamp youre using.

john walker's workshop · 11-15-2011, 08:25 AM

just find a shop with a press. then slip in the cage bearing and it's inner race and be sure there's no binding. the area inside of that flange distorts easily. i saw a 914 once where the cage bearing froze up inside 1st gear and the rear wheels locked up, skidding the car to a stop. it wasn't in 1st at the time either. an hours old rebuild from a local shop.