Dana 41 differential - want to "tighten it up" som |
Post Reply |
Author | |
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
Posted: 28 July 2017 at 6:05am |
I was doing the outer axle bearings and seals, you may have seen the pics in the other thread. The axle is on the stands by itself.
Upon putting in the new bearings and seals together I noticed that the pinion has a couple degrees of rotational play (lash?). When turning the pinion I can feel it turning by itself just a little before engaging the ring gear. I didn't mess with the pinion bearings at all so hopefully the pinion depth is ok. The lash is not very bad but I can feel it, and -- without the oil in the differential -- hear the gears engage if I spin the yoke back and forth. I am thinking if I adjust the shims between the carrier beating and the ring gear I can bring the ring gear a bit closer to the pinion and eliminate the lash... But the darn thing just won't come out. I tried two pry bars. Do I really need that silly pumpkin spreader tool?? |
|
Bruce W
Member Joined: 29 July 2005 Location: Northeast Colorado Status: Online Points: 9648 |
Post Options
Thanks(1)
|
When the gears are manufactured, the final step is to "lap" them together - they are run with an abrasive lapping compound in the contact area so they are basically "worn in" together. All the time since then, they've been doing the same thing, only a lot slower - wearing in, getting used to each other, developing a wear pattern. If you change the backlash, you will move the contact patch out of that wear pattern, and will likely make the rear noisy and accelerate wear.
You say that the pinion "has a couple degrees of rational play". It should have some. The proper way to measure that is by setting up a dial indicator on the ring gear and measure how much "rotational play" there is in the ring before it moves the pinion. If it's only a little more than the spec for new gears I would not try to change it. If the case (carrier) is tight in the housing and does not want to come out, it's a sign that the side bearings are not worn. In my opinion from what I have read, I'd say that it's not broken - don't try to fix it. BW
|
|
It is NOT a Jeep Willys! It is a Willys jeep.
Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You! We Have Miles to Jeep, Before We Sleep. |
|
Unkamonkey
Member Joined: 23 Mar. 2016 Location: Greeley CO Status: Offline Points: 2093 |
Post Options
Thanks(0)
|
Pictures would be nice to see the gear mesh pattern.
I have set up industrial equipment with a 18 inch ring gear before. It would just make it a bit more clear to us. Edited by Unkamonkey - 28 July 2017 at 8:25am |
|
uncamonkey
|
|
JeepSaffer
Member Joined: 26 Sep. 2014 Location: South Africa Status: Offline Points: 1181 |
Post Options
Thanks(0)
|
As Bruce says, some lash is SUPPOSED to be there. The obvious question is "how much?", but we don't have to rely on guess work or feel for this. The manual sets the permissible range between 0.005" to 0.010".
No human is able to gauge this accurately by hand, so my advice is to get yourself or borrow a dial indicator and measure it properly. Then you know whether it is within limits or not. Too tight or too loose will all have their long term consequences. Do it right and you will sleep easily knowing that it is set up as intended in the factory. Guess by hand and you will always wonder if your ongoing axle problems/noise/wear are caused by the backlash being possibly out of spec. 0.02.
|
|
1948 CJ2A #204853 in South Africa
|
|
JeepSaffer
Member Joined: 26 Sep. 2014 Location: South Africa Status: Offline Points: 1181 |
Post Options
Thanks(0)
|
If you DO need to get the diff carrier out, I made a "bridge" to span the case from side to side. This enabled me to grab the pumpkin with a regular puller and pull it out. If I had a puller with longer legs then my bridge could have had longer legs too, to give more space for the ring gear to come out. But I managed just fine by lifting the bridge legs on each side with a block of wood when I ran out of space. It's a simple $10 solution that is far easier than making a spreader, which can permanently damage your diff case if you overdo it, or if you leave the spreader on for too long the case can take a permanent set.
Here a pic of the setup for a dial indicator to measure the ring gear backlash. Good luck! Mike |
|
1948 CJ2A #204853 in South Africa
|
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
will measure the lash with a dial indicator tonight and report back!
|
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
I measured it before heading to work; I couldn't imagine waiting all day to do this.
It's at Edited by konstan - 28 July 2017 at 3:28pm |
|
SE Kansas 46 CJ-2A
Member Sponsor Member x 3 Joined: 22 Jan. 2016 Location: S.E. Kansas Status: Offline Points: 3190 |
Post Options
Thanks(0)
|
I have to agree with Bruce. If it isn't broke, don't try to fix it.
I owned and operated a driveline shop for 18 years, and customers would come in from time to time with a situation similar to yours. I would advise them to leave it as it is and just drive it. Some would take my advice, others wouldn't. Most of the time those that didn't take my advice ended up getting new replacement gearsets sooner than later. Put simply, you can't "tighten up" a ring and pinion setup. It changes the relationship that has already been established at the factory and causes noise and accelerated wear. If you decide to move the ring gear into the pinion to reduce the lash, be prepared to replace the whole setup in a thousand miles or so. Fourteen or fifteen thousandths lash is not unusual for a gearset that has been in service for several years. Provided that it has the proper lubrication, it should see several thousand miles of service. Take Bruce's advice to heart, he is telling it to you straight. Bruce said: When the gears are manufactured, the final step is to "lap" them together - they are run with an abrasive lapping compound in the contact area so they are basically "worn in" together. All the time since then, they've been doing the same thing, only a lot slower - wearing in, getting used to each other, developing a wear pattern. If you change the backlash, you will move the contact patch out of that wear pattern, and will likely make the rear noisy and accelerate wear. You say that the pinion "has a couple degrees of rational play". It should have some. The proper way to measure that is by setting up a dial indicator on the ring gear and measure how much "rotational play" there is in the ring before it moves the pinion. If it's only a little more than the spec for new gears I would not try to change it. If the case (carrier) is tight in the housing and does not want to come out, it's a sign that the side bearings are not worn. In my opinion from what I have read, I'd say that it's not broken - don't try to fix it. BW |
|
46 CJ-2A #64462 "Ol' Red" (bought April 1969)(second owner)(12 V, 11" brakes, M-38 frame, MD Juan tub)
U.S. Coast Guard Chief Petty Officer(ret.) U.S. Army Vietnam veteran and damned proud of it. |
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
Well, that sounds very good, I am relieved that I don't need to pull it out if I can live with 0.014
What bothered me in the first place was that I could actually hear the lash, not the actual amount of it... sitting right next to the front axle, comparing the yoke action, the front is smooth as can be (but its still filled with oil, I haven't tackled it yet)... I'll plan on buttoning it all up and moving on to the next thing on the list! Thanks guys!
|
|
SE Kansas 46 CJ-2A
Member Sponsor Member x 3 Joined: 22 Jan. 2016 Location: S.E. Kansas Status: Offline Points: 3190 |
Post Options
Thanks(0)
|
When there is the proper lubricant in the axle, the lash isn't so noticeable. The front still has oil in it and would be smoother and less noisy.
Depending on whether your rig has had hub-locks on it for most of its life or just drive flanges, the wear could be minimal. If it has had drive flanges, the wear on the front could match the rear. With hub locks and most of the drive time on the pavement the wear might not be very evident. All of this is dependent, of course, with the proper lubricant in place. One of the worst things that can happen is to run the axles under water and let that water rust inside the housing. The water can get in through breather openings and can be sucked in through a pinion seal if the axle is warm from use and is cooled down by the water. The rust acts as an abrasive and causes gear oil emulsification which in turn is less effective as a lubricant. If your axles are immersed in water for any length of time, it would be a good idea to drain them and replace the gear oil. |
|
46 CJ-2A #64462 "Ol' Red" (bought April 1969)(second owner)(12 V, 11" brakes, M-38 frame, MD Juan tub)
U.S. Coast Guard Chief Petty Officer(ret.) U.S. Army Vietnam veteran and damned proud of it. |
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
No, no evidence of someone leaving water and letting it rust... no rust on the axleshafts either, so it doesn't look like it spent time underwater...
|
|
cpt logger
Member Joined: 23 Sep. 2012 Location: Western Colorad Status: Offline Points: 3040 |
Post Options
Thanks(0)
|
Konstan, FWIW, My 1959 F150 has 90 degrees of that backlash in its rear axle. It has had the same amount for over 30 years & 275,000 miles so far. I change the gear lube every decade whether it needs it or not. There have been no iron filings in the old lube.
I have had a complete spare rear axle assembly sitting in my barn for the same amount of time. I got the spare for when the original axle fails. I am still waiting for it to fail. I do use the truck as a farm truck. So it does not get babied. I hope this eases your mind a bit. |
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
I love it!!! It knows you are waiting for it to fail. Is is dead-set on proving you wrong :)
|
|
Flatfender Ben
Member Joined: 13 July 2014 Location: Nyssa OR Status: Offline Points: 2657 |
Post Options
Thanks(0)
|
Don't forget to put that ring gear bolt back in... assuming you removed it?
Or install one if it was missing. Thanks for posting this question I've often wondered about this. Thanks to all who posted answers. |
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
All of the bolts were either loose or not torqued very tight... I read that it's a common occurence. The one missing in the picture, I removed to get a better look at the retainer.
I will reinstall the bolt but waiting on a new set of retainers, some of them just cracked when I tightened the carrier bolts. Thanks!
|
|
SE Kansas 46 CJ-2A
Member Sponsor Member x 3 Joined: 22 Jan. 2016 Location: S.E. Kansas Status: Offline Points: 3190 |
Post Options
Thanks(0)
|
...or get the holes and bolts oil-free and use Loctite.
|
|
46 CJ-2A #64462 "Ol' Red" (bought April 1969)(second owner)(12 V, 11" brakes, M-38 frame, MD Juan tub)
U.S. Coast Guard Chief Petty Officer(ret.) U.S. Army Vietnam veteran and damned proud of it. |
|
konstan
Member Joined: 22 Aug. 2016 Location: South Carolina Status: Offline Points: 351 |
Post Options
Thanks(0)
|
That I will do too but I want to have the proper retainers in there as well!
|
|
Post Reply | |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |