Need to match pinion and ring gears?

[bx23barry]

You guys can do/believe anything you want but the fact is ring and pinion gears are matched and as such are sold/installed in sets for a alot of real reasons. I would love to see a correct patten on an unmatched set. It would be a first for me and I've been in the auto/equipment industry for over 30 years.

 

[Soundguy]

Now that you explained how it broke.. I vote for replacing both. If there were extra stress loads on the pinion.. it could have gouged, deformed or caused alot of extra wear and stress on the ring gear.

If you can't suitable chase the nut so that it holds at it's specified torque value, file or grind the weld out, get a new nut, and screw it on, and then once assembled, tack it in place... don't over do it.. just tack, to make it captive..

Soundguy

I did a little more work on it tonight, mostly focused on re-tapping the crossed threads for the mounting nut so the axle can be remounted correctly.

I tried tried removing the pinion shaft, and it turns out you can't get a drift against it without removing the drive shafts, which means I really need to tear it all down anyway. Given this, I'll probably end up replacing both gears.

All the adjustment is via shims that set the depth of the pinion shaft. The workshop manual only calls for adjusting the backlash by swapping shims. There is no other adjustment. The probability is high that the shims I have will be wrong and I'll have to order new shims, which will mean another week or more waiting for parts. I could have ordered (maybe should have) one of each available size, but with 8 different sizes, I decided not to. Maybe I'll get lucky with what I have.

 

[BTDT]

So when you get the old ring gear out, bolt it to a piece of flat aluminum and you will have you a redneck ashtray. Use the pinion for a paperweight. Ok, maybe this is the start of a new thread--What kind of old junk have you recycled into something else (fan blade for wind vane, piston for ashtray, etc)?

Good luck on your rebuild, keep us posted (with pictures).

 

[hayden]

Uummm, you bring up a good point about the side loads. In addition to the ring gear, I'm now wondering if the bearings that hold the input shaft might have been damaged? I'll have to take a closer look when I pull it apart the rest of the way.

I'm probably going to see if my dealer has any of the adjusting shims and just buy them. I would guess they are a buck or two each, so if for $20 I can get the job done a week earlier, it's worth it.

Just to complicate things further, I'll need to put the whole thing back together temporarily (without 4WD of course) for the weekend because I have some wood splitting that really needs to get done. I'll just run in 2WD and don't see any harm or risk in it.

Oh, yes, regarding replacing the welded nut - I'd love to do exactly what you are saying, but can't. The nut is welded to the top side of a frame plate with the engine sitting over it. I don't think there is any way to get either a grinder or welder tip in to it. I'll keep investigating, but currently it's not looking good unless I want to remove the engine.

 

[Soundguy]

It probably wouldn't hurt to knock that seal out and repalce the bearing too, as you are now thinking. Now that we know how it was damaged, it's clear there was alot of pressure there when that shaft sheared. You'd hate to get it back together, and have the bearing die and wipe the seal out and loose the oil and hose the new gears. I know this stuff is mission creep.. but sometimes it pays to invest another hour and few more bucks just to ensure the problem is really completely addressed.

While you are at it.. i'd take a mic or dial caliper and check the bearing carrier for 'round'.

Yep.. sounds like a tough deal on the nut. Here's a question... does the bolt protrude thru the nut any? If so, any chance you can get a slim 'jamb' nut to set on topand help lock her down? Or would a wrench not have any access to that area either?

good luck.. post pics, and keep us informed.

Soundguy

Uummm, you bring up a good point about the side loads. In addition to the ring gear, I'm now wondering if the bearings that hold the input shaft might have been damaged? I'll have to take a closer look when I pull it apart the rest of the way.

I'm probably going to see if my dealer has any of the adjusting shims and just buy them. I would guess they are a buck or two each, so if for $20 I can get the job done a week earlier, it's worth it.

Just to complicate things further, I'll need to put the whole thing back together temporarily (without 4WD of course) for the weekend because I have some wood splitting that really needs to get done. I'll just run in 2WD and don't see any harm or risk in it.

Oh, yes, regarding replacing the welded nut - I'd love to do exactly what you are saying, but can't. The nut is welded to the top side of a frame plate with the engine sitting over it. I don't think there is any way to get either a grinder or welder tip in to it. I'll keep investigating, but currently it's not looking good unless I want to remove the engine.

 

[RobJ]

You guys can do/believe anything you want but the fact is ring and pinion gears are matched and as such are sold/installed in sets for a alot of real reasons. I would love to see a correct patten on an unmatched set. It would be a first for me and I've been in the auto/equipment industry for over 30 years.

This is an interesting side discussion, 30 years ago I would totally agree (I'm 46 BTW). But I'm willing to bet the ring and pinions in small vehicles (not giant dump trucks) are made in Mexico or China or somewhere besides the US. We export the highly acccurate machines and they pay someone $1. per hour to put in a blank, then remove it. With the computer driven machines, they have an accuracy of .001 or even .0001. They can check themselves with lasers, etc. So why would a company need to waste time in matching them up if they are exactly right. There are many other parts in our tractor that see more wear and they are not fitted to each other. You think it matters if you have 3 boxes of rod bearings and you drop them and they get mixed up? No. You think every bearing and race in our tractor is hand fitted. No. Gears in the tranny, hydrostic parts, hand fitted? Doubt it. Pistons, PTO shafts, crank shafts hand fitted? All done on a machine then checked for spec. Engines, trannys are built on an assembly line, just like the front end. Parts are grabbed from a box and put in. A rebuilt engine probably has more hand checked parts because the mechinic should be looking for these things because the engine has some time on it.

Why do they say do a 50 hour service, to remove junk left in and high wear items during break end. If everything was hand fitted, why would we need a break in period? Everything fits perfectly??

Rob

 

[Soundguy]

Interesting point about the tranny. I know lots of shops that just go in and repalce the gear with the bad tooth, then button back up. by all rights.. all the engine hp goes thru that new unfitted or used / salvage gear, just like it goes thru the ring and pinion.

I can see replacing as a set if there is significant waer differences.. But if the parts are not factor matched sets anyway.. but rather just milled to spec, then grouped.. then if you are matching up a very low wear item to a new one.. you should be good to go. now.. matching up a high warer item to a new item might be a problem.. etc. I would guess we need to hear from a gear hobber that makes ring and pinion gears, and hear how they are doing it now... I.E. matchine each set, or producing 5000 of each on a precisiol cnc/lathe/mill, then boxing up in set and shipping.. etc.

Soundguy

 

[RobJ]

I would guess we need to hear from a gear hobber that makes ring and pinion gears, and hear how they are doing it now... I.E. matchine each set, or producing 5000 of each on a precisiol cnc/lathe/mill, then boxing up in set and shipping.. etc.

Soundguy

Hablo espanol?
说中国人
を話してください
Eh?



Rob

 

[Soundguy]

>Hablo espanol?
>I would guess we need to hear from a gear hobber that makes ring and pinion gears, and hear how they are doing it >now... I.E. >matchine each set, or producing 5000 of each on a precisiol cnc/lathe/mill, then boxing up in set and >shipping.. etc.

First.. i think that would be " ?Habla Espanol "

I.E. matchinG each set, or producing 5000 of each on a precisioN cnc/lathe/mill, then boxing up in set and shipping.. etc.

I got 2 letters wrong.. a "G" and a "N"

Soundguy

 

[hayden]

This is an interesting side discussion, 30 years ago I would totally agree (I'm 46 BTW). But I'm willing to bet the ring and pinions in small vehicles (not giant dump trucks) are made in Mexico or China or somewhere besides the US. We export the highly acccurate machines and they pay someone $1. per hour to put in a blank, then remove it. With the computer driven machines, they have an accuracy of .001 or even .0001. They can check themselves with lasers, etc. So why would a company need to waste time in matching them up if they are exactly right. There are many other parts in our tractor that see more wear and they are not fitted to each other. You think it matters if you have 3 boxes of rod bearings and you drop them and they get mixed up? No. You think every bearing and race in our tractor is hand fitted. No. Gears in the tranny, hydrostic parts, hand fitted? Doubt it. Pistons, PTO shafts, crank shafts hand fitted? All done on a machine then checked for spec. Engines, trannys are built on an assembly line, just like the front end. Parts are grabbed from a box and put in. A rebuilt engine probably has more hand checked parts because the mechinic should be looking for these things because the engine has some time on it.

Why do they say do a 50 hour service, to remove junk left in and high wear items during break end. If everything was hand fitted, why would we need a break in period? Everything fits perfectly??

Rob

I tend to agree. I don't know how you do volume manufacturing otherwise. This is why I suspect the it's more about ensuring the gears are wear-matched than about gears that were manufactured for each other.

In general, if I have something apart I'll replace anything that's suspect. In this case it's more about having to do a significantly larger tear-down to get at the incremental part, adn there is little compelling evidence that it needs to be replaced.

Now that I"ve discovered I need to tear the whole thing down anyway, it's more moot. I've already bought the part - why not put it in?