2002 Terex 760 Extend-a-hoe 4x4 up keep/repairs

[just-a-mechanic]

Hey Guys I am new here and I own a 2002 Terex Backhoe as the description states.

I have scoured the internet and short of buying parts from Russia, looks like I'm left to my own devices for wear items and common upkeep.

I would by from Russia but cant get any shops to respond to my emails... must think I'm scamming them

This Terex has Carraro axels and a Turner Transmission Shuttle/synchro Shift.

I have a leaking Front left axel oil seal past the reduction gears. So, I need to find these parts. I have to look up the axle model number and ill post it here.

I am looking for the wear pads on the extend-a-hoe internal and external. No luck anywhere, well except Russia. Good luck getting Terex Dealerships to help, including corporate. I am aware of the story on Terex and how things came to be.

I'm thinking about cutting my own using Teflon flat sheet. I have a CNC Mill and can cut the profiles, would be great to get a pattern and thickness to match the new ones. Mine were missing at the end of the dipperstick - I guess the previous owner "forgot" to put them back in. So the Lower section of the dipper does not have any wear pads installed.

Also depending where you look: operator Manual, Maintenance Manual and 760B Maintenance Manual all state to put Different Oils into the reduction gears, front axle and rear axle. 80W API GL4 for the Rear and 80W-90 API GL5 for the Front, Seems That Mobil Fluid 424 Works in everything,(Alternate fluids chart in manual). (I don't think that is the best idea for the reduction gears) I plan to use 80W Gear oil, but I have wet brakes so I need to make sure its compatible.

AW46 For hydraulic fluid.

Anyone Know who makes the hydraulic system? I'm preparing to gather information and repair parts source before I have a problem.

This machine is new to me, and is for Farm use.

I am doing a full service before I start using this machine. It is very confusing because none of the manuals agree with each other, oils and viscosities.

 

[JL Sargent]

Welcome to the forum. I don't know squat about your machine. Surely you can find what you need stateside. I do see those machines occasionally so I would think somebody supports them in Alabama.

 

[oceanobob]

Once Terex sold the division in 2017, have you made contact with the new company: Mecalac? There is a Mecalac office in MA listed on their website.

 

[just-a-mechanic]

I did contact Mecalac, they pushed me to a local dealer in MS, they told me they dont carry the parts any longer.... sorry!

The dealer was in Southaven, MS. Terex Dealer

 

[oceanobob]

sad to learn of this situation with these machines: United Rentals in these parts sold quite a few of these by bringing them in as part of the local rental fleet then making either lease and rent to own to move the machines...
Assuming you have tried all the internet aftermarket supply houses?

 

[kevin biles]

i work for wvdoh and I feel your pain trying to get parts for these machines. we have a company in charleston wv that supplies our parts and i just rebuilt the entire boom assy on a 760b they should be able to get what you need sometimes may take upto 3-4 weks for shipping from england or wherever they are now the company is wv tractor in charleston wv

 

[kevin biles]

do you need the round "pucks" or the square with 2 corners missing? there are also shims that go beneath of both
i have both at work and can get you measurements if needed

 

[just-a-mechanic]

Hey guys tanks for the replies.

The previous owner never changed the oil at 1000hrs like he was supposed to, so I had a lot of water contamination in the gear oil. I flushed with diesel fuel and followed that up with 85-90 GL5 oil. Ill change that again in 10hrs of run-time. I was started to have a rusting issue, that is the reason for flush and to remove as much moisture as I could. I also flushed the rear reduction gear assemblies the same way. They both had horribly dirty/water contaminated oil, the right side only took one flush to get the diesel fuel looking red when drained. However the left took two tries, man that was really nasty. [Could not see any rust tho] I put 80-90w GL5 in those too. Anyone have a recommendation on oil? The manual has the rear at 80w GL4 oil and the front at 85-90 GL5. I would think that GL4 Would meet GL5 requirements, So i'm using it in everything but the shuttle-shift of course.

I have since pulled the drive axles out of the front of the machine and replaced the seals and bushings. The Front right side, someone has been inside of. The left side was sealed and still had the O-ring seal in the housing. I had to replace both half shafts to the wheel side because of seal wear. This includes the crosses in the axle shaft assembly, I could not for the life of me get enough clearance to remove the bearing caps from them. So i had to knock them out and replace them. Any one have a tip on this, removing the bearing caps from this particular drive shaft? There is not enough room to drive out the cap the entire way, about 3/4 and could not pull the cap out with a bench vise either. I used the proper tool to remove them, a U-Joint C frame. Wish i could have salvaged the U-Joints but I could not [needle's fell out, and destroyed the grease seal], so I had to replace them with sub-par units. Chinese that is.... I wasn't about to pay 100$ each for U-Joints. [I might have to pay it later on...]

I also resealed and replaced the needle bearings in both front reduction gear assemblies, Not because of wear or finding an issue, but because I was already there, wasn't a horrible job, but a heavy job!

In the rear axle I had a seal leak from the pinion seal. I purchased a seal and installed it in the housing. Wouldn't you know, that the seal can go back approx 1 1/2 inches? That's too deep for the drive yoke to seal properly, So I purchased another 45$ seal and put it in with about of an 1/8th of an inch below the face. Worked well the second time, that will teach me to drive in without checking first.

The oil was drained from the rear axle as well, it was nasty but not horrible compared to the others. It seemed awful thin, like hydraulic oil, not gear oil. Probably UTF, So i flushed with cheap hydraulic oil after spinning the axle over with the engine running with no-load, then drain it as before. If I see there is a lot of contaminates I will make the decision on using diesel fuel or not, for a further flush.

I replaced the drive shaft u-joint straps going from the shuttle shift to the Rear axle and bolts that I found from a case dealer. Someone was kind enough to use red lock tight on the bolts, so i had to use my tig on the hardware - just enough to break the bond, just to remove them, thanks guy.

My Caliper for the Parking brake needed brake pads, wouldn't you know that I could not find these brake pads? So I created a 3d model and cut my own pads out, using my wife's car front brake pads [Had them in storage]. Worked like a charm, now I have a working parking brake, Better than OEM.

I had to place an order for steering column bearings from Hungry they were DG199 Koyo bearings. My bearings wore a flat spot and became one way locking bearings. The PO must have been spraying wd-40 or something to mask the issue, or just for lubrication. The manual has you replace the entire steering column as it is not serviceable. These bearings are not available state side anywhere, I tried for weeks and multiple bearing houses. They are rubber isolated, with a caged needle bearing. I bought the last ones I could find on the internet.

I purchased a steering PIN and spherical bearing from Europe, mine was wore so badly that the spherical bearing came out of its bore. Waiting for that at the moment of writing this. Should be another week or two.

The radiator's exterior fin's were completely stopped up from oil and dirt accumulation without being properly cleaned. So I had to remove the oil cooler and radiator and spend two days cleaning and spraying with coil cleaner, and carefully using a pressure washer with a 40 deg tip.

I replaced the hydraulic oil with AW46 oil, I had the loader bucket cylinder blow a seal and while rebuilding/resealing it, found the piston seal nut rusted, which the hydraulic shop could not remove, so the rod had to be cut and back-built to re-seal it. Also, had pitting in the cylinder wall. So i took that as an immediate replace the hydraulic fluid now. So I have ran about 30 Gallons through the system trying to remove the now hydrated oil from the system. Ill give it a bit of time, then replace some more. Perhaps I ll send off an oil sample to see where I am in water content.

The extend a hoe, wear pads I cut with the cnc machine. I used Teflon sheet for the upper/lower large plate. I made them 1/2 inch thick If i remember correctly, also the side pucks were 3/4 inch thick x 2in. I used HDPE for the side pads.

That is all the major things I have done so far. But I've almost have her serviced and ready to go. Ill come back asking alot of questions because I still need the front axle center pin and bushing. Also need to rebuild the backhoe swing cylinders as the scraper seals are gone. The gland seal will be gone shortly.

Thanks for the offer of help btw guys, I did not get any email notifications of replies to this thread. So now I know youre here, ill start responding to your questions!


Thanks!

 

[just-a-mechanic]

Attached are the PDF Files for the Axles in this Particular Backhoe. Same for the 760B as well.

I got all my parts from Joseph Industries, OEM Carraro parts and the best price I could find.

Sheila Bednarcik | Sales Representative
P: 800-321-9983 x189
F: 330-342-3895
SBednarcik@Joseph.com | B2B.Joseph.com

 

[just-a-mechanic]

Hey Kevin, If you could get me measurements of the shimstock and nominal sizes of the shims, both the flat plate and the round pucks I would be very grateful to you!

Next I need the Interior Shim stock and the Rear Wear Plates, but Mine are ok there for the time being.

I need a 10W ATF fluid to change out the shuttle shift oil, any recommendations? Will any DEX III work? Or should I be worried?

If someone needs the service manual let me know. I will try to get it into a cloud service, since its 80MB.

 

[just-a-mechanic]

Here are some pictures btw: we all like pictures!




I just installed the Axle back in to the housing. I put the plastic bag over it for the night and knocked off.


This is the Spicer Sliding Joint from the Shuttle Shift to the Rear Axle.


Here is the Elusive DG199 Steering Column Bearing

 

[JL Sargent]

You are gonna be ready to do some digging now that you've about got this sorted out. What a pain though.

 

[just-a-mechanic]

Sargent; Absolutely, I should be done with the service this weekend. Whoo, Its been a journey.

Anyone have a suggest on the ATF for the shuttle shift: 10W ATF fluid to change out the shuttle shift oil, any recommendations? Will any DEX III work?

 

[oceanobob]

Lotta respect for all the work that was accomplished. Hope the machine performs well for ye.

 

[just-a-mechanic]

Thanks Oceanobob!

I put 8 hours of time on her this weekend. I took down about 15 fairly large trees and regraded some of the ground where they sat. I had to road her about a mile from my house for a diesel refill. I did notice that in 4th gear I get slipping... well I'm not 100% sure because I think I'm just conditioned to worry now that I have seen the mistreatment of this machine. The engine speed remained constant but my speed decreased when going up a large hill. So I am not exactly sure what performance I should get from her or what the was normally expected since I do not have the experience of what it should feel like. The machine felt fine otherwise, plenty of power and I have no leaks other than a few drips from the swing cylinders. [That's the only thing I've got going for me!]

I will have to buy a wet gauge and check pressures in this shuttle shift after changing the oil. Hopefully the clutch plates are not burned up.

I also need to check the pressure in the hydraulic pump. Seems to me that I'm not getting enough flow for three actions at once. Example: Curling bucket, extending the dipper and retracting at once. Think... digging out roots around trees! Perhaps a priority valve? Or maybe I'm expecting too much?

My Shuttle Shift is a COM T4-2032 which is not covered by this manual. I'm betting it is basically the same thing as listed in the Attached Manual below.

Where can I get a rebuild kit for the Shuttle shift?.... any thoughts? I will be contacting Turner to see what they say as well.

I have a HUSCO 6600 Series MonoBlock Hydraulics.. anyone know where to get kits for these? The internet is not helpful at all with this backhoe. Ill call Husco and see what they say too, better not say its proprietary and that I have to go through the dealer!

6610 G3 L is the part number on one of the mono block. I'm pretty sure both are 6600 Series, just with more spools. The FL is a 3 spool, the backhoe is 7 spool If i'm not mistaken.

 

[just-a-mechanic]

Attached is the parts listing for the COM-T4-2032 shuttle shift. These parts are available through Joseph Industries.

This is the shuttle shift in Terex 760 series Backhoes and many other's.

 

[just-a-mechanic]

Well looks like I’ve ran into a problem. I was changing my shuttle shift oil and removed the dust cover to see if the torque converter had a drain bolt.

Here’s what I found when I removed it.

Can someone point me to what they belive this is?

There are only two sides to this thing. The engine and the shuttle shift.

So either a main bearing for the shuttle shift pump or the engine. I do not believe this engine would have a radial bearing in it like this. But then again I’m open to any advise. The backhoe runs fine and well enough. I did not have anything to really report in the shuttle shift suction screen either.



Could this be the remains of a starter? The bendix mechanism perhaps? Since I see the springs. I can’t fathom something else in that area using springs in that manner.

 

[Delmer]

I'm guessing a sprag clutch. that could be from a starter bendix, or possibly from the driveline. Sure hope it's from a former starter.

Those are cylindrical right? not tapered?

 

[just-a-mechanic]

Delmer,

Yes these are cylindrical. Which leads me to believe it’s from the a previous starter assembly. And not the tapered roller bearings which would need preloading, such as a driveline system.

 

[Clawed Backster]

Wow, I looked at one of those brand new about 20? years ago. They wanted $39,000 for it, which seemed pretty good to me. Sure glad I didn't buy it, now that I see what a pain it is to get parts.