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Shark Bait
10-20-2009, 12:57 PM
I'm rebuilding my SM420 because it was popping out of 3rd gear and the synchro wasn't working. Can anyone tell me what tool I need to pull the bearing retainer off the input shaft? And where can I get one? It should un-screw from the shaft. TIA. :hill:

Corbet
10-20-2009, 01:47 PM
looks like you need a spanner wrench but I'm no expert.

Shark Bait
10-20-2009, 02:02 PM
I talked to Novak who I got the rebuild kit from. It guess it's reverse thread. :o

Shark Bait
10-21-2009, 11:00 AM
Well, here is some of the problems:

jettaglxdriver
10-21-2009, 11:04 AM
Spanner wrench. Not sure where to get them locally? Anyone know if some place like whistler bearing would have them?

A set like this would be helpful here. Sounds like they are called "Face spanner wrenches" These are adjustable but some are sold that are non adjustable.

http://www.google.com/products/catalog?hl=en&q=spanner+wrench+set&safe=active&cid=6430024913588287338&sa=title#p

Some more
http://www.thefind.com/hardware/browse-armstrong-face-spanner-wrench

http://www.grainger.com/Grainger/items/1APC1

http://www.amazon.com/Armstrong-34-154-Adjustable-Spanner-Wrench/dp/B00004WBHH

Uncle Ben
10-21-2009, 11:57 AM
Spanner wrench. Not sure where to get them locally? Anyone know if some place like whistler bearing would have them?

A set like this would be helpful here. Sounds like they are called "Face spanner wrenches" These are adjustable but some are sold that are non adjustable.

http://www.google.com/products/catalog?hl=en&q=spanner+wrench+set&safe=active&cid=6430024913588287338&sa=title#p

Some more
http://www.thefind.com/hardware/browse-armstrong-face-spanner-wrench

http://www.grainger.com/Grainger/items/1APC1

http://www.amazon.com/Armstrong-34-154-Adjustable-Spanner-Wrench/dp/B00004WBHH


My good one is a Snap on but the cheap one I have in my Cruiser is a Harbor Freight. They won't know they have one if you ask.....they should be in the front counter display.

Shark Bait
10-21-2009, 12:03 PM
I got it off and back on with a punch and a hammer. It's reverse thread. Thanks, though. :D

Shark Bait
10-21-2009, 11:33 PM
So, does anyone think the 3rd gear teeth in my previous post look too worn to use?

Uncle Ben
10-22-2009, 06:16 AM
So, does anyone think the 3rd gear teeth in my previous post look too worn to use?

I, personally, would re-use it, but what do I know?

Corbet
10-22-2009, 08:49 AM
well you've got it all opened up now. How expensive is the part? That's the way I always look at things.

rover67
10-22-2009, 09:00 AM
I'd reuse it.. but that's just me... looks like it was just rust at one point.

but, corbet does have a point.

Uncle Ben
10-22-2009, 09:41 AM
I'd reuse it.. but that's just me... looks like it was just rust at one point.

but, corbet does have a point.

Gears prefer to be changed with their mating gear. They tend to whine about being separated at least for a while till they forget their old partner and shape to the ways of their new partner. Then again it's a 420 IN AN FJ-40 so actually noticing more whine than usual might not be possible.....

jettaglxdriver
10-22-2009, 09:52 AM
I like this one. Variable span, interchangeable pins to fit the holes and a torque wrench hole at the end for setting torque.

http://www.amazon.com/gp/product/B000F5JMEA/ref=s9_simz_gw_s0_p60_i4?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-2&pf_rd_r=06SBAJFP86DHHYRYCHWD&pf_rd_t=101&pf_rd_p=470938631&pf_rd_i=507846

Uncle Ben
10-22-2009, 10:14 AM
I like this one. Variable span, interchangeable pins to fit the holes and a torque wrench hole at the end for setting torque.

http://www.amazon.com/gp/product/B000F5JMEA/ref=s9_simz_gw_s0_p60_i4?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-2&pf_rd_r=06SBAJFP86DHHYRYCHWD&pf_rd_t=101&pf_rd_p=470938631&pf_rd_i=507846

That is a decent one although the torque would be drastically incorrect by gauging it at the end of a lever! Hard to tell on the picture but it also appears that the pins are interference fit which besides the fact that they will get lost makes the inside of my wrist and fore arm ache at the thought of sliding across cast iron flashing on a diff when the tip shifts and the spanner comes off under load. Wow....hows that for a run on sentence?

EDIT: I Googled the manufacturer and part number and found better pictures and the pins are threaded as one would hope. Here is one for several bucks less.... http://www.sjdiscounttools.com/otc6613.html

Shark Bait
10-22-2009, 10:30 AM
Thanks guys. Novak (http://www.novak-adapt.com/index.htm) said they made their own tool with a piece of flat stock, hole in the center, and two bolts on either side at the correct distance. They sell SM420 rebuilds, among other things. :D

corsair23
10-22-2009, 12:29 PM
Hey Chris...

On a scale from 1 to 10, how difficult has the rebuild been? My SM420 seems to suffer from similar maladies that yours did (aside from popping out of 3rd).

Shark Bait
10-22-2009, 12:34 PM
Hey Chris...

On a scale from 1 to 10, how difficult has the rebuild been? My SM420 seems to suffer from similar maladies that yours did (aside from popping out of 3rd).
Not too bad. It's still apart on my bench. You're welcome to come by and check it out.

rover67
10-22-2009, 01:45 PM
Gears prefer to be changed with their mating gear. They tend to whine about being separated at least for a while till they forget their old partner and shape to the ways of their new partner. Then again it's a 420 IN AN FJ-40 so actually noticing more whine than usual might not be possible.....

true...

more reason to leave it..

Shark Bait
01-16-2010, 08:52 PM
Well, my rebuild job didn't fix my problems. I'm still grinding going in to 3rd gear. It's really stiff going in to 2nd. And now I have a big leak coming out the front. I need to either find another SM420 or a Toyota tranny. H42s are pretty plentiful.

I think the Orion is OK, but I have a loud clicking noise I can't locate yet. I'm hoping it's OK and maybe a problem in the front axle.

The drag is just the time it's going to take to pull it all out and put it all in again. I was really hoping to have some time before Moab to be able to drive this around and make sure it's solid. Oh well....

corsair23
01-16-2010, 09:00 PM
I thought the grinding going into 3rd was typical :hill:

Sorry to hear the rebuild didn't turn out the way you wanted...

wesintl
01-16-2010, 10:03 PM
have you tried double clutch shifting?

Shark Bait
01-16-2010, 10:17 PM
have you tried double clutch shifting?

Yeah. It's actually good downshifting from 4th to 3rd, but not up from 2nd to 3rd. The bigger issue is the fluid leak. :(