Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Topics concerning the Tesla front and rear drive unit drop-in board
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by SuperV8 »

Just thinking out loud!

1: How about an oil/ATF cooled rotor rather than coolant? I would think much less likely to leak - at the expense of lower heat transfer.

2: How does the model 3 front drive unit cool? This is also an induction motor - so will also get heated - and I can't see any coolant fittings on the case - so I presume either internally oil cooled? or not cooled at all?
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

I think the M3 front induction motor uses an oil-to-water heat exchanger (see exchanger on left side of the pic below). It's cooled by oil internally, and the oil is pumped to the exchanger that's bolted to the exterior of the DU. Additionally, the coolant loop cools the inverter electronics first (see the coolant fitting on the right of the pic below) before routing to the heat exchanger, so the more temperature-sensitive electronics get the cooler coolant.

Tesla Model 3 FDU, top view
Tesla Model 3 FDU, top view

My suggestion idea No. 7 above was to use a non-water-containing coolant (basically: glycol) instead of a 50/50 water mix, so any leakage would cause no corrosion nor electrical harm. I bought a gallon of a typical gycol coolant, and a spare Tesla coolant pump and PWM module, but it's all sitting on one of my workbenches right now, waiting for some testing time.

I don't know if it's practical to convert the LDU to oil cooling for the rotor, and an external heat exchanger, but it's possible. The external aluminum coolant tube that the LDU uses to move coolant from the inverter side to the rotor side, could be interrupted, and a small closed-loop oil circuit established for the rotor side, plus a heat exchanger.

This might be practical for recycled LDUs in EV conversions, but possibly not practical for Model S installations, which is what Howard is aiming to achieve.

My drawing tools are limited, but here's a mockup of a oil-to-water heat exchanger, plumbed in to an LDU:

Tesla Model S LDU, Inverter-to-Rotor coolant flow
Tesla Model S LDU, Inverter-to-Rotor coolant flow
Tesla Model S LDU, idea for oil-cooled rotor
Tesla Model S LDU, idea for oil-cooled rotor
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

SuperV8 wrote: Mon Feb 13, 2023 4:00 pm Just thinking out loud!

1: How about an oil/ATF cooled rotor rather than coolant? I would think much less likely to leak - at the expense of lower heat transfer.

2: How does the model 3 front drive unit cool? This is also an induction motor - so will also get heated - and I can't see any coolant fittings on the case - so I presume either internally oil cooled? or not cooled at all?
Looking at Tesla motor's evolution. Number of motor has increased with each motor's power reducing. So dual and now Plaid's triple motor. Each motor doesn't have to put out as much power. Furthermore, Tesla has evolved to add more perm magnets (which all other EV use) so I guess less rotor heat. So it seems heat density is going down with the newer designs as well as using oil with a coolant heat exchanger like a matured transmission coolant technology for decades now.

As for adding a oil cooling loop. Besides the fitting and oil flow pump power requirements. Also need to consider if want to use oil in the much smaller flowing passages within inverter phase plates. It seems desirable to just cool the rotor with oil and leave the rest to remain with coolant. This would require a custom manifold with proper channel divisions which gets into yet another sourcing + manufacturing item.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

Heard from an owner with 2015 Tesla Model S dual motor that had an HV fault. He traced it to front motor coolant leak in the inverter.

Reviewed the front motor tear down. Inverter and oil heat exchanger are coolant cooled. Then oil cools gears AND rotor+stator. There is oil splashing in the rotor/stator chamber including on the rotor bearing. I guess no more cooling fluid leak worries haha. Prius also runs an cools its rotor and stator in the ATF.

The more I dig into this car and EVs in general, water and electricity don't mix haha.

Tesla LDU rebuild website https://sites.google.com/view/teslaldu
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

Fortunately, LDU inverter-side coolant leaks are rare :)
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

asavage wrote: Wed Mar 01, 2023 1:25 am Fortunately, LDU inverter-side coolant leaks are rare :)
057 comments he'd seen inverter leaks from non Tesla assembled LDU (sounds frequent but 057 has been around awhile, since the early Model S days). From my rebuild effort, I know the 3 o-rings for the 3 phase plate cooling passages are easy to crimp on reinstall. Heard about it during my rebuild effort so took extra care

https://teslamotorsclub.com/tmc/posts/7159517/

There are also 2 coolant temp sensor o-rings but these have proper seat for the o-ring in the casing. Hard to mess up.

https://teslamotorsclub.com/tmc/attachm ... eg.870575/
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

BTW my water and electricity don't mix comment was more than the inverter coolant. Tesla has a major water ingress problem everywhere particular in the front end where car travels forward and rain comes down and travels backwards. Made a diagram

https://teslamotorsclub.com/tmc/posts/7420101/

Tesla's evolution so far seems to be keep on burying stuff torwards inner drier parts of the car. M3 still suffers from HV heater failure regularly due to water ingress. Then there is inverter and battery itself which has coolant running internally with connection + high vibration environment.

I think the water ingress issue is probably going to take a couple of decades and 3-4 generation of designs to improve. Not an easy problem. HV in the front end and low to the ground.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by tesland »

We opened a drive unit for the first time.
This one is making the (in)famous milling noise when driving.
no leakage in the motor found.
Which bearings are the usual suspects. Is there a way to check the bearings
IMHO the bearings of the rotor shafts are noisy
Any suggestions are welcome.

https://youtube.com/shorts/LgdjdP0V-ok?feature=share
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

From memory (ie this is not Gospel):
  • The far end rotor bearing (the one that gets the most coolant ingress from the leaky seal at the far end coolant manifold, by the rotor speed encoder)
  • The near end rotor bearing (due to early production units not having enough rotor grounding (via Aegis ring brush) for stray AC induced rotor currents)
  • And the pinion bearing at the rotor near end (due to the later use of "ceramic" ball bearings on the the previous bearings, moving the rotor ground path into the gearbox).
There are LOTS of threads and images available for these, including brg replacement part Nos. I'm not aware of any of the other gearbox brgs being an issue in typical use; racing or higher output use cases might have some other gearbox brg failures, but I don't read in those circles.

The coolant seal replacement is the primary focus of this thread, so reading it top to bottom will give you the current thoughts on replacement/modification. If you have no coolant leakage past the far end rotor seal, yet have milling noise, I'd guess you have an early production (2012-2013?) LDU with a failed Aegis ring and steel balls in the rotor bearings. Replacing the bearings (for noise) and the seal (because you don't really have a choice, once it's been disturbed) will likely get you back in service; the pinion bearing may or may not "need" replacement; if it was my budget, I'd replace it anyway, but my budget isn't yours, so it's in your lap on that one.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

tesland wrote: Tue Mar 14, 2023 4:51 pm We opened a drive unit for the first time.
This one is making the (in)famous milling noise when driving.
no leakage in the motor found.
Which bearings are the usual suspects. Is there a way to check the bearings
IMHO the bearings of the rotor shafts are noisy
Any suggestions are welcome.

https://youtube.com/shorts/LgdjdP0V-ok?feature=share
Can you post the following

- sticker on the LDU? It will provide orig manufacturing year, reman status, revision level.
- PN on the rotor bearings

Know history of the LDU?

These guys tested the 6208 bearing this way for the electric micro arc damage.



When I installed new bearings (2x rotor, 6207/6208), there was no effective way I could test it. Read here

https://sites.google.com/view/teslaldu/ ... 746uk62z9v
Tesla LDU rebuild website https://sites.google.com/view/teslaldu
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

Unless I knew the brgs were installed <10k miles previously, I wouldn't even try to evaluate them, they'd be replaced. I am not that tight-fisted that USD$300 (or whatever) for two rotor brgs would seriously be a consideration; I do not want to take this apart more than once a year, these locations are known problem areas for this assembly, and trying to skimp here is for low-budget/lots-of-time-available/don't-need-high-availability situations.

That was preface to say: I do not test inexpensive bearings, I don't evaluate their condition or listen to them more than a few seconds; I am a parts-replacer when in this situation. I have the advantage of owning the tools needed to do that, so the raw materials cost is my only cost, other than time.

Of course, it's quite easy to damage bearings during installation, esp. the ceramic replacements. Use a press or find a way to minimize impact side loads on ball bearings during install.

[Roller brgs are much more tolerant of shock loads, and can carry much higher loads in general, but due to their increased contact area, they also have a lot more drag, so they're never used for high-speed applications.]
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

asavage wrote: Wed Mar 15, 2023 12:10 am Unless I knew the brgs were installed <10k miles previously, I wouldn't even try to evaluate them, they'd be replaced. I am not that tight-fisted that USD$300 (or whatever) for two rotor brgs would seriously be a consideration; I do not want to take this apart more than once a year, these locations are known problem areas for this assembly, and trying to skimp here is for low-budget/lots-of-time-available/don't-need-high-availability situations.

That was preface to say: I do not test inexpensive bearings, I don't evaluate their condition or listen to them more than a few seconds; I am a parts-replacer when in this situation. I have the advantage of owning the tools needed to do that, so the raw materials cost is my only cost, other than time.

Of course, it's quite easy to damage bearings during installation, esp. the ceramic replacements. Use a press or find a way to minimize impact side loads on ball bearings during install.

[Roller brgs are much more tolerant of shock loads, and can carry much higher loads in general, but due to their increased contact area, they also have a lot more drag, so they're never used for high-speed applications.]
Messing with interference mount bearings on the LDU isn't trivial. Unfortunately also first time for me removing and installing bearings. Here are the challenges

- Pulling the rotor bearings. I used a impact gun to accelerate process. Unfortunately the puller shifted during the rattle impact and glanced the bearing seat and nick it during the pull. Don't know if this is preventing the bearing to seat flat when installed. It looked fine by eye but who knows.

- Tapped in the rotor bearings with a PVC pipe/endcap. I think this is a mistake as its a huge dampening agent requiring much more force and many more 3lb hammer blows. A metal pipe probably would have been better to carry the impact momentum to seat the bearing quicker.

- Thought about how to mount rotor bearings on with a press and has quite a few challenges. Its not clear can anchor the rotor on the large copper cylinder as its unknown how firm the shaft and copper cylinders are mounted/bonded. Best to anchor the rotor on the ends. However, the rotor standing on its narrow ends with some pipes as anchors will stand > 20 inches tall with a 70lb rotor weight. When standing on the spline side, the copper rotor weight is even higher center of gravity for greater instability. Fortunately probably doesn't need much press pressure to get it in. But it is far from trivial and no one has provide a clear guideline. All the videos/pics shows just tapping it in with variety of tools.

I did find this on my speed sensor inspection @ 2k miles. Wondering if my speed related whine is the rotor bearings destroying itself. I guess have to pull the LDU to find out.

viewtopic.php?p=52682#p52682
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by hmejl »

Hey folks
I have now pulled my third ldu apart, all bearings changed and seals to.
But we get a bearing noise from 10 to 30 mph when acc slowly any idear of what could have happend ???

bonus info
we had a 0,6 mm groove on the rotor but found a local company there grinded the shaft down, and the put a new chrome face on the shaft ant then grinded it back to messurement and it is perfect surface for a shaft seal now

Image
Image
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

hmejl wrote: Wed May 10, 2023 1:10 pm Hey folks
I have now pulled my third ldu apart, all bearings changed and seals to.
But we get a bearing noise from 10 to 30 mph when acc slowly any idear of what could have happend ???

bonus info
we had a 0,6 mm groove on the rotor but found a local company there grinded the shaft down, and the put a new chrome face on the shaft ant then grinded it back to messurement and it is perfect surface for a shaft seal now

Image
Image
- What bearings did you change? 2x rotor bearing, 2x primary shaft bearing? (6207/6208)
- How did you install these interference fit bearings?
- Did you close the gearbox horizontally or vertically? I closed mine upside down horizontally (to minimize damaging the inverter) I'd imagine vertical assembly is ideal but would probably need to build a box as the entire assembly is ~3 feet tall without flat ends.

My Tesla installed reman LDU had a 30mph decel whine and found 6207 spun in its bore during my rebuild. After my rebuild, has a speed based whine > 20mph. Have 3500 miles now, not sure its getting worse and sound seem to change with the warming weather.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by hmejl »

howardc64 wrote: Thu May 18, 2023 8:19 pm - What bearings did you change? 2x rotor bearing, 2x primary shaft bearing? (6207/6208)
- How did you install these interference fit bearings?
- Did you close the gearbox horizontally or vertically? I closed mine upside down horizontally (to minimize damaging the inverter) I'd imagine vertical assembly is ideal but would probably need to build a box as the entire assembly is ~3 feet tall without flat ends.

My Tesla installed reman LDU had a 30mph decel whine and found 6207 spun in its bore during my rebuild. After my rebuild, has a speed based whine > 20mph. Have 3500 miles now, not sure its getting worse and sound seem to change with the warming weather.
Hey Howardc64
I have replaced all the bearings. and mountet all the bearing in a press. But i have just dismantle another one and meassured all the bearing gaps and such. And found not all bearings are all seatet on the shafts, and might think i also have a bearing there is spinning
So i will take it apart again.
Thanks for the answer
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

hmejl wrote: Mon May 22, 2023 5:50 am Hey Howardc64
I have replaced all the bearings. and mountet all the bearing in a press. But i have just dismantle another one and meassured all the bearing gaps and such. And found not all bearings are all seatet on the shafts, and might think i also have a bearing there is spinning
So i will take it apart again.
Thanks for the answer
We collected rebuild info from various LDUs

- Mine and other earlier LDU's 6207 didn't seem to have retaining compound. Mine spun in the bore with bearing surface to the bore showing marks (link to pic below in revision table)

- Mine and other intermediate shaft's counter bore bearing (FAG) had about 1cm x 2mm of red retaining compound on the side of outer cage in the bore. @asavage suggested this would accomplish nothing so I reinstalled (new) FAG bearing without retaining compound.The FAG bearing was removed by hand while ATF was abundant (just after splitting the gearbox) so definitely wasn't secured in the bore in anyway. I thought about putting retaining compound on the surface between bearing and bore but the gap is so tight I was afraid of just end up jamming the bearing on install (no ATF lubrication if using retaining compound) and damaging it on pull.

https://sites.google.com/view/teslaldu/ ... hgytkyz6c5
Tesla LDU rebuild website https://sites.google.com/view/teslaldu
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

howardc64 wrote: Mon May 22, 2023 6:57 pm - Mine and other intermediate shaft's counter bore bearing (FAG) had about 1cm x 2mm of red retaining compound on the side of outer cage in the bore. @asavage suggested this would accomplish nothing . . .
To clarify: the retaining compound visible was at the bottom of the counterbore, not on the sides, and there is insufficient surface area at the bottom of the counterbore to accomplish anything when using retaining compound there. Anaerobic retaining compounds -- indeed, all retaining compounds -- are effective as a function of surface area, which is why they're applied to the OD of the outside brg race and/or inside of the bore to which the brg is fitted.

From what I saw, the visible compound in Howard's gearbox was either incorrectly/sloppily applied, or was excess that was wiped off the counterbore's sides during assembly, which is the most charitable interpretation. Certainly, "loose" retaining compound at the bottom of the counterbore serves no function, but it may be a side-effect of applying excess during assembly. I advised Howard to not place any there directly, but only to the counterbore's sides prior to fitting the brg.

I usually see this kind of assembly designed with the brg having a light interference fit, but properly fit -- looser -- plus retaining compound has been an alternative fitment I've seen. Tesla may have started building the LDU using one technique and later switched to another.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

Here are some possible variables compared to Tesla's new/rebuilt LDU

- Might be assembled vertically. New ones are probably robots with proper jig for vertical orientation. For us DIYers, need to build a jig help stand vertically or assemble without inverter and put it on afterwards (and caution on inverter coolant o-ring crimping)

- Above posts on retaining compound for 6207 and FAG bearing.

- I've seen youtube videos of assembly transmission gearbox halves when replacing a case half that cracked. Need to size and change the shim. Only shim on the LDU is the rear diff which us DIYers are just reuse.

- All Tesla bearings have VC4521 which we don't know what it stands for. Can't buy these

https://sites.google.com/view/teslaldu/ ... ephk6i38z3

- Cheaper sourcing from Acorn/Eriks in EU are mostly Italy country of origin (COO) SKFs. Not USA COO (thats what Tesla installs) or Germany COO (More expensive). Seems unlikely SKF QC would yield significant difference in terms of COO. However, do note SKF has COO all over including likes if Brazil etc.

- Tesla ATF is actually SK Lubricants 202-B. PITA to get it from Tesla. Mobil1 LV ATF HP is 202-B spec (what I used). Rav4 LDU calls for Dex VI (I also tried, no difference in my whine)

- Necessary to clean (shipping oil) and soak the bearing in ATF prior to use? I've seen tranny rebuilders soak some parts in ATF prior to assembly. LDU ATF level (1.6L+) is far lower then the 6207 and FAG (highest) bearing. FAG bearing has no fluid feed channel so I assume lubrication just come from spinning/slinging. When pulling the fill plug after many miles, I do notice it seems completely dry with no metallic mud.[/list]

Anyhow, I have a slight whine but maybe original Tesla rebuilt was suspect already with its spun 6207. Since others are encountering noises... thought I outline all the variables I can think of.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by spiff »

Hi Everyone,
I've been combing through all these pages, Howard's site and Johan's youtube videos (thanks to everyone who's contributed to this body of knowledge!) and need some tips. I've disassembled my LDU and am now in the process of re-assembly after waiting months to get new seals (Chengming) and one rotor bearing.

Does anyone have a picture or sequence of how the circlips, seals, bearings go in on either end of the rotor? I unfortunately didn't take pics or record it when I was disassembling and now realize there may be some variability in how to do it.

Johan,
I noticed you had a cad model you referred to in some of your videos. Do you have a clear picture you'd be able to provide? I seem to have the brush ring that provides electrical connection to the rotor....

Thanks in advance!
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

spiff wrote: Sun Jun 18, 2023 2:24 am Hi Everyone,
I've been combing through all these pages, Howard's site and Johan's youtube videos (thanks to everyone who's contributed to this body of knowledge!) and need some tips. I've disassembled my LDU and am now in the process of re-assembly after waiting months to get new seals (Chengming) and one rotor bearing.

Does anyone have a picture or sequence of how the circlips, seals, bearings go in on either end of the rotor? I unfortunately didn't take pics or record it when I was disassembling and now realize there may be some variability in how to do it.

Johan,
I noticed you had a cad model you referred to in some of your videos. Do you have a clear picture you'd be able to provide? I seem to have the brush ring that provides electrical connection to the rotor....

Thanks in advance!
Sounds like you lost track of the sequence of parts on both end of the rotor. Here is what I recall
Screenshot 2023-06-18 at 9.04.17 AM.png
On the outward facing end of the rotor, Johan's CAD shows in the following 2 posts for reference

viewtopic.php?p=42902#p42902

=====

One thing I did not post and likely pretty key is final closing of the 2 halves of the gearbox. If assembled horizontally like Johan and me, the 3 shafts with their C3 bearings will be tilted AND if the shafts and bearings have been left out long time (2mo for me while studying and gathering parts) All the ATF will be gone and sliding in bearings into bores or shafts into bearing inner face will be tight. During my test fit, I was able to get the 2 halves mate up but on 2nd attempt with RTV, it wouldn't close by hand. Had to close it up with bolting the 2 halves. I have a whine and wonder if this is the cause.

Ideally, assembling the 2 halves should be done vertically. But this gets really tall. Probably the motor end without the rotor/endplate on so it sits nice and flat on the stator windings is best way. Then mate up the inverter half vertically with a light coat of ATF on bores/shafts/bearing faces where they mate along with RTV on the case (if do this on a horizontal assembly, ATF will run towards the case edges where RTV is). Have a helper to route the stator temp sensor wiring and generally aid as this assembly will be like 3 feet tall when assembled.

So the general assembly sequence is

Motor Halve (first phase)
- Assemble the primary shaft seal (if replaced)
- all 3 shaft+bearings+ATF pump assembled in the motor half

Mating the 2 halve
- mate the 2 halves vertically per above
- route temperature sensor cable from motor half to inverter half (sleeved makes it way easier, see my TMC post)
- reconnect the temp sensor, close up case around the inverter

Motor half (2nd phase)
- can be done horizontally
- Insert rotor into stator cavity with 2 ceramic bearings mounted
- mount the end plate, tap in the reluctor wheel. The circlip,
- tests fit + stretch PTFE seal, mount it to the coolant manifold, mount manifold onto the end plate. Read my TMC post carefully, PTFE seal installations completely different than typical rubber seal install and where most inexperienced will fail.

Hope this helps.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

howardc64 wrote: Sun Jun 18, 2023 6:51 am Had to close it up with bolting the 2 halves.
For others: this is never a good idea. There are probably thousands of motorcycle case halves cracked and in scrapyards from using this technique. I've done it myself (when I was 14 and working in a motorcycle repair shop!). Though I'm glad you got away with it with only a mystery-cause whine.

Never use the fixing bolts to draw assembly halves together.
Al Savage
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by spiff »

Thank you both!! This is invaluable information and advice. I'll post everthing in my build log when I'm ready.

Thanks again to this community.
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by howardc64 »

asavage wrote: Sun Jun 18, 2023 4:27 pm For others: this is never a good idea. There are probably thousands of motorcycle case halves cracked and in scrapyards from using this technique. I've done it myself (when I was 14 and working in a motorcycle repair shop!). Though I'm glad you got away with it with only a mystery-cause whine.

Never use the fixing bolts to draw assembly halves together.
In my case, it wasn't much resistance on final (after test) assembly. But was just enough so can't push it together by hand. Handling is difficult as the design doesn't provide much holding places with RTV on the mating surfaces and inverter exposed in the open (need to connect temp sensor). Need to remember if assembled horizontally, then the case is sitting on something. If not a slippery machine shop stainless table top, then there is resistance where the case sit. I even assembled mine upside down as inverter has no solid metal to sit on right side up. All of this @ 300lbs. Generally, not handling friendly at all.

But yes, vertical assembly is best. Everything is aligned and straight. Can ATF all the mating bearing+shaft surfaces and won't drip over the RTV sealant for the case halves.

But it makes it really tall. But probably okay if rotor/endplate isn't inserted and sit flat on the stator windings. Its the heavier end anyways. And also need a 2nd pair of hands to route the temp sensor lines doing the mating. Can make it shorter if inverter is removed. But inverter isn't very heavy so probably not an issue sitting up high and would have to risk crimping the inverter coolant o-rings if removed.

Tesla probably manufacturing original LDU with big robots and rebuilders probably have a JIG to assist with vertical assembly.
Tesla LDU rebuild website https://sites.google.com/view/teslaldu
2013 Model S85 3rd (Reman RevQ) LDU on 2017 @40k. Coolant seal leak discovered in 8/2022 @ 72k miles
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by spiff »

Okay. Got the rotor back in and end plate on but not the coolant seal and cover yet. That's enough for tonight. In the future, does anyone know what kind of grease goes on the spline end of the shaft?
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Re: Tesla Large Drive Unit (LDU) Motor Teardown and maintenance

Post by asavage »

I believe that no-one has information about what grease(s) Tesla has used over the years, and the subject comes up every so often.
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2014 RAV4 EV
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