NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > Modified Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

Modified Tech Discussion Forum for Tech related discussion for Modified XJ's and MJ's.

Reply
 
Thread Tools Display Modes
  #1  
Old June 26th, 2005, 22:12
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
D30 restoration

Got a good deal on a complete D30 axle with the right gear I needed, but after taking it apart I found mud and water inside plus it’s leaking fluid and there were no shims what so ever.
In other words I have some work to do, before it goes into my driver.
Also the hubs do not appear to be in great shape

On a positive note, the axle shafts are new with bigger U-joints, the gear is in good shape, and my old hubs can be transferred onto the “new” axle.

Could I be looking in the wrong place for these shims?

I thought the shims should be between the carrier bearing and the axle seal right?

BTW the carrier just fell out when I took the caps off.

I got thinking I should take this to a mechanic and have it set up then I thought, “hey-wait a minute” this thing is already out of my Jeep I’ve got about 4 weeks to get it set up, plus I have one of the best resources right here. I read up on the theory and I have a digital camera if I need your help but…

Before I start I figure I need to get this thing cleaned first, then where do I get the magnetic dial indicator? Are they common? Are they expensive?

I guess I’ll need to order a master install kit, any suggestions for that?
Reply With Quote
  #2  
Old June 27th, 2005, 00:48
Rawbrown's Avatar
Rawbrown Rawbrown is offline
NAXJA Forum User
 
Join Date: Jan 2004
Location: Encinitas, CA
Posts: 2,008
Re: D30 restoration

doesn't sound to bad...
mudd and water, yummy. was there any oil in there? I do see D30 carriers fall out all the time. no big deal. for starters, the shims are between the bearings and carrier. they are pressed on. but really you don't need to touch them unless the bearings are bad. start with a visual inspection of the carrier bearing races. that will tell you a big story on its condition. send me a pic and I can tell you. inspect the bearings themselves. make sure there are no pits on the rollers.
pull the pinion. 1-1/8" socket and a big inpact gun. remove the yoke and knock the pinion out with a brass or copper hammer. remove the pinion seal and catch the outer pinion bearing as it falls. toss the seal and save the small oil slinger (big washer), bearing, and preload shims. the preload shims will limit how far the outer bearing can press onto the pinion which limits how tight the bearings will be. inspect the pinion bearings but only press them out of the housing if they need to be replaced.
using a long bar of steel, knock the axle seals into the housing from the outside. now clean... I really don't care about the outside unless its nasty. just as long as you get the inside clean. just knock the loose stuff out of the inside of the axle tubs so that the shafts don't take anything with them on assembly. once its all clean then its time to put it all back together. start with hte axle seals. put a small bead of silicon around the "step" on hte outside diameter, right on the corner of the step. then install your pinion, put hte preload shims on, then the bearing and slinger. temporarly install hte yoke and tighten it down to 10-15 seconds of your impact gun at full power. check preload by rotating the pinion with a toque wrench rated for 0-50 inch pounds. I believe used bearings take about 8 inlb. once verified then remove the yoke but not hte pinion or bearings. install the pinion seal and then the yoke. use a new pinion nut and gun it down again.
by this point you have allready taken the liberty of cleaning the carrier. use a miniral based carb cleaner as it leaves no residue but it should displace the water that pressent. go ahead and install the carrier back into the housing. using locktight, torque the bearing caps down to 60 lbft. make sure that you have identified right from left. youll notice a letter of the alphabet stamped on the housing gasket surface next to the bearing caps. on the left side the letter might be turned vertical and on the right side it may be turned horizontal. match the stamp on the bearing caps to its side of the housing and correct orientation.
put the cover on it and put it in the jeep. save the shafts and hubs till after the axle is bolted into your jeep. this is just to make it e4asier to move around.
have fun.
BTW, i have no clue who to suggest for your rebuild kit. good luck.
Reply With Quote
  #3  
Old June 27th, 2005, 01:09
NotMatt's Avatar
NotMatt NotMatt is offline
NAXJA Forum User
 
Join Date: Feb 2004
Location: Wenatchee, WA
Posts: 495
Re: D30 restoration

Rawbrown pretty much nailed it.

The shims are between the bearings and the carrier, so none should fall out when you pull the carrier (or it falls out in this case, which is not necessarily a bad thing, just check that there's no side to side play in it when you put it back in).

One thing you might check is see if the tag that's held on by two of the diff cover bolts is still there and if it tells you the same thing the gears say... if it's not there or says something different than what the gears are, they could've been swapped in at some point and may or may not be setup correctly (I've bought axles where the person selling pulled the gears and just tossed a different set in without setting them up and didn't tell me. luckily I decided to check things out before I ran it). If it looks like it's been tampered with, it probably has... so check over it carefully.

Good luck with your project, gears scare a lot of people but aren't some kind of voodoo magic or anything... just takes some patience and a few special tools here and there.

BTW, I bought my dial indicator at sears in the tool aisle for about 30 bucks. It's not the best (infact, it kind of sucks), but it works and I've setup a few diffs with it so far with no problems.
Reply With Quote
  #4  
Old June 27th, 2005, 01:39
5-90's Avatar
5-90 5-90 is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Hammerspace
Posts: 18,821
Re: D30 restoration

If you plan on doing a fair bit of work, drop MSC Direct a line and ask for their catalogue - it's hardbound, bigger than most phone books, and it's FREE! Loaded with goodies for you to find useful (I get one every year.)

A "Magnetic Dial Indicator" is actually two items - a dial indicator (which can be had with measuring ranges anywhere from 1/4" to 4") and a magnetic base - the base has a magnet (obviously!) for mounting the indicator to any ferrous object, and a mount of some sort for an indicator.

There are several different styles of base for dial indicators, but the advantage of the mag base is that you don't need to get a bolt hole - just any fairly flat surface - and it measures movement relative to the housing without having to account for any movement of the housing proper (which you would have to do if the indicator were resting on the workbench.)

The average dial indicator base will hold pretty much indicator, so you can sub with another style of indicator or a unit with more or less travel or accuracy, as the situation requires.

Fowler, Federal, Starrett, SPI, Mitutoyo, and Browne and Sharp all make excellent measuring instruments. MSC has good prices - I order from them frequently.

While you've got it torn to bits, take a good bright light (this is why I usually have a SureFire in my pocket, and one in my toolbox) and check all of the bearing surfaces (under the diff carrier saddles, in the pinion pocket, at the wheels) for any discolouration or striations - this indicates a spun bearing and that the housing should be discarded. This is due to the fact that metal is discoloured due to heat - and that the temper and hardness of the metal are wrecked. It is theoretically possible to re-heat-treat the axle and recover the proper hardness and temper, but to do so on something that big would be cost-prohibitive.

5-90
Reply With Quote
  #5  
Old June 27th, 2005, 07:56
Rawbrown's Avatar
Rawbrown Rawbrown is offline
NAXJA Forum User
 
Join Date: Jan 2004
Location: Encinitas, CA
Posts: 2,008
Re: D30 restoration

alot of detail but a few things..
you don't really need to spend to much money on the dial indicator. while its critical to have the proper backlash. the measurment doesn't need to be made with an expensive tool. checking backlash is relative to itself in that as long as everything holds its position while you are checking it will be accurate. so having the indicator mounted to the workbench while checking backlash is not a big deal. you only care about the range of movement.
and having the backlash within ballpark range is good. its the pattern of the marking compound that tells the whole story.
the mag base advantage is ease of use and quick attach and detach.
having a spun bearings is a major issue. it can be repaired but its usally easier to find a new housing. since it is cast, i don't know if there is much heat treating and tempering that goes on.
Reply With Quote
  #6  
Old June 27th, 2005, 15:03
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
Re: D30 restoration

thanks for the replies

yes I'm one of those people who think gears are voodo stuff, but I'm hoping to rid this fear from my life

bearing look OK defiantly not spun, hope to put up a pic tonight.

is there such a thing as gear pattern checking compound goo, or is it just water based craft paint?
Reply With Quote
  #7  
Old June 29th, 2005, 09:44
Heb80 Heb80 is offline
NAXJA Forum User
 
Join Date: Mar 2005
Location: Harrisburg, PA
Posts: 58
Re: D30 restoration

The gear marking compound comes with the install kit... but I'm sure you can get it by itself too.

I recently regeared my D30 and Chrysler 8.25 and bought all the tools at Harbor frieght for less than $200. Dial indicator, magnetic base, micrometer, 300 ft/lbs torque wrench, bearing separator, 2 Jaw puller, and even a 12ton shop press. The shop press wasn't really necessary, just made things easier, and I'm sure it will come in handy in the future. The bearing separator is a little on the cheap side and I even had to grind the edge a bit sharper to reach under the bearing. All-in-all, $200 of tools is a good investment and still cheaper than paying someone else to do it, not to mention the learning experience.

Oh and I got my 50 lbs fish scale (for pinion preload) at walmart for another $5.
Reply With Quote
  #8  
Old June 29th, 2005, 11:20
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
Re: D30 restoration

how do you use a fish scale for pinion preload?
I have a fish scale I 'don't have a inch pound wrench.
Reply With Quote
  #9  
Old June 29th, 2005, 11:35
Heb80 Heb80 is offline
NAXJA Forum User
 
Join Date: Mar 2005
Location: Harrisburg, PA
Posts: 58
Re: D30 restoration

Quote:
Originally Posted by john mitchell
how do you use a fish scale for pinion preload?
I have a fish scale I 'don't have a inch pound wrench.
Torque is a measurement of Force x Distance. So 10 inch-lbs is simply that, 10 pounds at the end of a 1" lever, or 1 pound at the end of a 10" lever. So if you fasten a fish scale to the yoke and apply a force you can calculate the rotating torque.

Measure the distance from the center of the pinion nut to the center of a U-Strap bolt hole (should be 1 1/2" to 2"). Then put a bolt in the hole, hang the scale from it, and pull. Be sure to rotate the angle that you pull at as the pinion starts to turn. You should always pull 90 degrees from the lever arm, that being the imaginary line from center of pinion nut to U-strap bolt.

Here's an example. If the distance from the center of the pinion nut to the bolt is 1.75" and you apply 16 pounds of force to rotate the poinion, 1.75"x16lbs = 28 inch-lbs.
Reply With Quote
  #10  
Old August 12th, 2005, 17:18
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
Re: D30 restoration

thanks for the great info so far.

Update:

After a lengthy delay I have torn into this project.

First thing I noticed was the bearing races are dull on the roller mating surface, not pitted just dull. Second I noticed the pinion was a little lose, so I tried to tighten it with an impact wrench on medium, but then the pinion got really really really really really hard to turn. This thing sounds like it was not set up properly.

Am I missing something?

I'm leaning toward getting at a master install kit and starting over myself.

What do you think?
Reply With Quote
  #11  
Old August 13th, 2005, 00:14
Lucas's Avatar
Lucas Lucas is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: ZOO YORK CITY
Posts: 1,106
Re: D30 restoration

Post pics of the bearing rollers. As for the pinion preload, you don't have enough shims underneath the outer pinion bearing. Keep adding .010" shims to the stack until you overshoot it (too little preload when spinning yoke),and then start subtracting height from the stack in smaller increments.
This is, of course, assuming you have all the necessary shims. If you haven't gotten an install kit, I suggest Yukon. You can find them a little cheaper than other brands if you shop around, they are totally complete (marking compound, brush, locktite), and use quality parts like timken.
Reply With Quote
  #12  
Old August 13th, 2005, 18:01
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
Re: D30 restoration



hope this works

The bearing looks about the same, Looks like the diff got full of mud and was run that way for a bit.
Reply With Quote
  #13  
Old August 15th, 2005, 18:30
john mitchell john mitchell is offline
NAXJA Forum User
 
Join Date: Nov 2003
Location: Kentucky
Posts: 115
Re: D30 restoration

no one?
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
CJ d30 Axle Q. XTrmXJ Tow Rigs and Trailers 5 April 20th, 2005 14:39
D30 disco axle to non disco? ChEwBaCcA Modified Tech Discussion 9 September 10th, 2004 14:41
1 D30 unit bearing 3 weeks old, 1 set of 297/760 D30 shafts, 1 D30 diff guard Safari Ary For Sale: Private Party Only. XJ ITEMS ONLY 10 June 17th, 2004 13:22
Solution to your D30 Hi Steer needs useless For Sale: Private Party Only. XJ ITEMS ONLY 3 December 9th, 2003 09:01
H.R. 1904, the Healthy Forests Restoration Act of 2003 Ed A. Stevens Land Use Forum 0 May 25th, 2003 15:24


All times are GMT -7. The time now is 02:30.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014