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Roadster Rear Blower Maintenance

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The guy told me 2.x fans mount in the bottom and sucks up all the dirt and crap. If you don't go in annually to have them cleaned, it will fail. Just passing info along.

That's because (if my memory serves me correct) the left blower on the dual blower upgrade (on the bottom) blows air up into the PEM, the right blower blows into the electric motor's cooling fins. I also believe they added another cooling fan up in the PEM. All this was done only after the dual fan/blower upgrade which the 2.0s didn't came stock. I believe Tesla only began putting two fans/blowers in the 2.x PEMS after identifying a cooling issue. I don't know where that cut-off is. And the previous design the single lower blower was trying to cool the motor down as well as force air up into the PEM.

Where as the 1.5 PEM there's only one fan (really a blower which is stronger) that doesn't get or need any assistance from the (motor cooling) blower down below. This blower is only dedicated to the electric motor. Menlo Park also confirmed that the 1.5 doesn't pick up as much dirt and grime from the road since the fan air pickup is right at the PEMs base, which still picks up ambient dust that adds up to dirt, but not as much or as heavy as force fed blower where the pickup is at the lowest rear part of the Roadster which gets the brunt of dirt / dust / leaves / twigs kicked up by the front wheels and underbelly of the car. Look at any video or picture of a 2.x getting cleaned out, its rather disgusting. The pick-up tube also should be cleaned and actually washed with fresh soapy water for a true cleaning, but the Rangers/Tesla doesn't do that. I don't even know if they blow the duct tube running from the lower blower up to the the PEM out.

From my analysis of searching the forums it appeared to me that the majority of the PEM failures were from 2.x Roadsters so if the survey indicated that the majority of failures came from 1.5s I have to disagree by the design of the PEM/Cooling as well as reading the posts on PEM failures and identifying what version of Roadster they were linked to. (granted there's approx. 500 1.5's and 1,950 2.x's in the world) To me, Tesla may have tried to address cooling the PEM better, but also had to reduce costs. Someone came up of piggy backing off the lower blower to get more airflow over the PEM bug ignored the fact that that's the worse place to pick up clean air. I'm sure their testing showed that this was a bad idea, there are tests showing the roadsters doing doughnuts in a dry dusty / dirty field. But they were under the gun again for delivery and stuck to it. When customers complained, they offered a dual blower setup, but that just forces more dirt up there faster into the PEM! Yes it does cool it down nicely but its still in the wrong location. If I owned a 2.x with the dual blower I'd find some way so that blower pulls fresh clean air from a high location, not low. And yes, we do hear that the 1.5 was built like a tank over and over again, reason being is that Tesla was not in cost savings mode but rather in proving ground mode. They put parts in there that were aircraft quality and more robust so that things would have a lower chance of failing. It looked and looks and feels like a quality component when opened up. When cost savings came into the picture the 2.x PEM took a hit, and a cheaper way to build it was applied. Not only cheaper in making, but cheaper to service. Hence allowing the Ranger to remove cables from the PEM from the top of the PEM and the front of the rear cargo bin. The faster a Ranger can service a Roadster, the more cars you can service for a given technician and more money you can make. People (in the forum) who've had their PEMs fail in their 2.x's felt like inferior parts were put in there and that was the root of the failure. I also came across a couple 2.x owners who had their PEM replaced twice as well as 3 times! Don't know why, but it sounds rather odd. I haven't seen a post yet of a 1.5 PEM being replaced that many times although there could be one. But I doubt it.

I feel confident in my 1.5 PEM and I'm already a year out of warranty. I'm doing my own PEM cleaning / maintenance here in a week or two and will be blowing the PEM out as well as the electric motor's cooling fins and cooling blower. Never had a switchpack issue and think if that would have went, it would have kaput already. My battery was replaced under warranty at 14k due to a problem internally with the 12v aux. power supply which is housed inside the main pack. Nice not having a 12v battery that runs dead, but then it makes the problem more complex if something fails. I don't see that failing again and happy Tesla covered it. Actually really happy my pack was replaced as I saw two sheets that were pulled down and way lower in capacity than the rest. My new pack is very healthy now and feel very confident with it. I also know how to treat it well, cool-downs, don't push it hard when below 50% SOC, keep it out of the hard sun during the summer, and target 50% SOC when sitting as much as possible. One thing to note is that when Tesla does a bleed test is that it does not show the full health of the pack. You can have sheets that are way lower than the rest and it will pass the bleed test fine. Bleed test just shows the pack can take a charge and discharge without an issue. It won't tell you if a sheet is dying due to a bad brick or cell unless its catastrophic. What Tesla has but doesn't show or tell you is a program that plots the health for each brick in each of the 9 sheets! That's the information that's key in REALLY knowing how healthy your pack is. You can see what sheets are pulled down and which ones are giving you a weak CAC value. And the only way to get this info is to become good friends with one of the engineers. Really wish this was a public diagnostic tool but ohh well.

At 28k I feel my Roadster has settled in pretty well and if something does come up I'll address it myself or if I don't have the tools/expertise I do have the connections that allow me to get it done properly without any need for an extended warranty.
 
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Thanks for the comments. Sounds like the 1.5 Roadsters just need to have their cooling fan inlet inspected and cleaned annually. Is that something that an owner can do if they jack up the car, or does it have to be done by Tesla?

Power has to be cut-off/shutdown properly from 400 Volt ESS to the PEM and the person doing the service must have technical knowledge on what they're doing. So if any of those you're unfamiliar with, then Tesla is the place you'll need to take it to.
 
Okay thanks. I thought maybe the fan inlet area just needed to accessed from underneath is it could be cleaned by hand.

No, its a pretty detailed job. Shutting down the power, disconnecting the wires, carefully sliding the PEM off and pulling the cover off, getting an air compressor and blowing out the PEM blower, heat sinks, and remove any debris. Then pulling the lower blower off, cleaning that out good with the air gun, blowing out the cooling fins of the motor, and clean up what was underneath the PEM / around the motor area.

I think some service centers skip cleaning the motor and possibly the lower blower at times. I like doing things myself since I have control on how good the cleaning is.

Biggest / most important part is ensuring you shut down the system properly and ensuring your safety. But if your not mechanically / electrically inclined, unaware of the dangers and where they're at, you don't want to go down this path. But if you're interested in knowing more, the best investment is to have a Ranger come out and do your annual maintenance, have a camera, take pictures, and don't hesitate to ask questions. This helps you understand and to properly take care of your Roadster even better.

Here's a video of a Ranger cleaning out the blowers/PEM of a 2.x Roadster:

 
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The guy told me 2.x fans mount in the bottom and sucks up all the dirt and crap. If you don't go in annually to have them cleaned, it will fail. Just passing info along.

In area with harsher conditions (for example, here) Tesla did an upgrade for 2.x where they put a box underneath the PEM that tries to prevent debris from getting in the fan assembly. Then they put an upgraded fan unit in. And they had to replace the rear sway bar to do this, so it was a fair bit of hardware. It does seem to help a lot.
 
That's because (if my memory serves me correct) the left blower on the dual blower upgrade (on the bottom) blows air up into the PEM, the right blower blows into the electric motor's cooling fins. I also believe they added another cooling fan up in the PEM. All this was done only after the dual fan/blower upgrade which the 2.0s didn't came stock. I believe Tesla only began putting two fans/blowers in the 2.x PEMS after identifying a cooling issue. I don't know where that cut-off is. And the previous design the single lower blower was trying to cool the motor down as well as force air up into the PEM.

A lot of your information is not quite correct. The 2.x always had dual blowers. They never had a cooling issue (except on a track). The upgrade did several things. First they made the blowers much more powerful. The PEM cools off very quickly and stays cool. They also switched to a variable-speed single motor design with sealed bearings that runs both blowers. They installed a "snow dam" that keeps most of the dirt and debris out of the cooling system that used to build up. You still have to clean it out once a year but it's nothing like it used to be. The techs have always cleaned my motor cooling fins and all ducts at the same time they cleaned the PEM. The PIA Roadster survey suggests that the 2.x PEMs have not been replaced as often as the 1.5's. However, the sample size is probably too small for any definitive conclusions.

Whether you have a 1.5 or 2.x I still think they should have a large dust filter. It would be a lot easier to replace that every year than all the work cleaning everything out. They need a cabin air intake filter too.
 
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A lot of your information is not quite correct. The 2.x always had dual blowers. They never had a cooling issue (except on a track). The upgrade did several things. First they made the blowers much more powerful. The PEM cools off very quickly and stays cool. They also switched to a variable-speed single motor design with sealed bearings that runs both blowers. They installed a "snow dam" that keeps most of the dirt and debris out of the cooling system that used to build up. You still have to clean it out once a year but it's nothing like it used to be. The techs have always cleaned my motor cooling fins and all ducts at the same time they cleaned the PEM. The PIA Roadster survey suggests that the 2.x PEMs have not been replaced as often as the 1.5's. However, the sample size is probably too small for any definitive conclusions.

Whether you have a 1.5 or 2.x I still think they should have a large dust filter. It would be a lot easier to replace that every year than all the work cleaning everything out. They need a cabin air intake filter too.

I really though I saw a 2.0 getting retro-fitted with a double blower from a single blower in Menlo Park and was talking to the technician about it. Why would they change out the rear swaybar if it had double blowers? Possibly the original double blower was way smaller? Secondly, why would they make the blowers more powerful if there wasn't any sign of a cooling problem? Just curious and wish I took pics of the blower upgrade. I don't see why they'd change a design if there wasn't a problem to address. I asked about getting the retrofit and they said if my PEM showed signs of overheating, which evidently some did, that they'd do the upgrade. But then later they mentioned it couldn't be done and I guess they remembered that I had a 1.5 :) I did have a 2.0 loaner with this upgrade and was amazed how fast it did cool the PEM down hence why I asked Tesla about the upgrade. But I never driven a 2.0 without the upgrade so I don't have anything to compare it to.

Happy Tesla up a solution from picking up salt and road debris. Unfortunately you have to live in a climate where snow is to get it :( I have to take a look at Doug's posted pics in the PEM thread to understand what they did. As for not having a dust filter, I can only say that there must be a pretty good restriction to airflow once that gets clogged up and my lead to worse problems.

- - - Updated - - -

There is room to run a duct from the driver's side intake port, over the rear wheel well cover, and down to the box around the blowers (I have the snow dam upgrade). I might give this a shot once my warranty expires.

That would be a great design to play with, and if you could find room to mount a replaceable filter over the inlet of the custom duct work that should keep things cleaner.
 
There are two parts to the upgrade. First, they remove the TWO fan/motor assemblies (1 for PEM, 1 for motor) and replace it with a single variable speed motor that has two fans attached.

Second, the remove the sway bar to make room for the huge box that prevents most junk from getting into the fans, and put in a new sway bar that goes around the box.

Hope that's more clear. Yeah it only works with 2.x PEMs. And yes it does cool things down faster than the original setup.
 
There are two parts to the upgrade. First, they remove the TWO fan/motor assemblies (1 for PEM, 1 for motor) and replace it with a single variable speed motor that has two fans attached.

Second, the remove the sway bar to make room for the huge box that prevents most junk from getting into the fans, and put in a new sway bar that goes around the box.

Hope that's more clear. Yeah it only works with 2.x PEMs. And yes it does cool things down faster than the original setup.

I see. Thanks Doug!
 
Just removed and blew out my 1.5 PEM. Very minimal signs of dust on the heat sinks that are on the lower portion of the PEM. Blew out the PEM blower, minor dust came out. Was going to remove the blower but no need to do it this time since there wasn't really anything in there that needed to be clean. This is after 1 year from the last annual Tesla maintenance. Removed my lower blower that cools the motor. Found out that the last technician or one before that broke all 4 mounting points of the blower shroud. They took a shortcut and forced it where they needed to loosen the rear mounting bolts (4) that hold the swaybar's bushings to the frame to give the shroud clearance. Instead they thought they could force it through a tight spot (between the carbon fiber cargo hull and swaybar) and broke it since all four corners of the very brittle fan shroud since all the corners were still on the bolts. The 4 rear swaybar bolts were never loosened! Ever. Emailed Telsa to let them know. No other way that would have broke just sitting there, there are two steel straight bar re-enforcements top/bottom that ensure even pressure is placed across the top and bottom bolts mounting points, someone stressed this part without taking time to do it right.

I'm sure I could go 2 years without blowing out the PEM on my 1.5, however my motor and top of the transmission was covered in that stupid stock crappy pad that came with the Roadster, the Brembo's, so I cleaned all that gunk and crap out of there. Back to pristine clean.
 
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NOT HAPPY. Tesla came back saying "They'll give me a price on the broken fan shroud." You know what, THIS THING WAS BROKEN BEFORE I REMOVED IT!!! I hate to rant, but I love Tesla but if they are not stepping up to the plate for breaking a simple cheap part they replace at cost that is clearly documented by my pictures of maintenance.

This is the reason why I NEVER WANT ANYONE to work on my car!

You're life is tied to the quality and safety of the maintenance done on your car. If done shabby, in a short cut method to save time and money, your life is on the line.

So HAPPY my dad who was an Engineer tough me the basics to take things apart, to understand how to trouble shoot things, to make them better if they broke. But bottom line, be trust worthy and take responsibility for what you're paid top $ and trained to do!!!
 
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And yes, it is louder than the original setup.

That's what I noticed from my 1.5 over the 2.0 with the upgrade. It was a loud beast charging, and that blower was always on. My 1.5 is quiet charging after some time which is nice. The 2.0 never shut up. The fan was always on while charging the 2.0 which to me was annoying since I was use to charging quiet.
I still don't understand how a dual motor dual blower setup took less room than a single motor dual blower setup. The swaybar got larger for the newer blower, I'd think it get smaller since there's one less motor driving and taking up space. Would be nice to see before and after pics of the mod.
 
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I too prefer the blower design of the 1.5. The PEM has an integrated fan and with it mounted high near the driver's air port above the door handle. The 2.x designs have both blowers mounted low and the pick up a lot of crap. My PEM has stayed quite clean.
 
Tesla gave me a call today, Sunday to make sure the issue was discussed in detail and to avoid any miscommunication on the broken blower shroud and motor shroud. Tesla is backing up their work and replacing the broken blower shroud as well as the broken motor cover. It appears that my original email was read wrong by them due to time and they mis-read that I wanted to purchase a new shroud and were under the impression it broke under normal driving conditions. Tesla re-read my email and follow ups and do agree that taking out/loosening the lower 4 bolts of the swaybar is protocol the technicians are to follow to properly remove the blower. They're also following up with different levels of managers in the service department to again make it clear to the technicians that no shortcuts are to be made when making repairs on customer's cars to ensure proper installation / removal of parts when any type of service is performed on a vehicle.

Happy that Tesla gave me a personal call on Sunday (which they didn't need to do) in order to get the exact details and to properly remedy the concern.

People do make mistakes, I do, but taking responsibility as well as action so the issue doesn't happen again is what's respectable and earns high regards.
 
Roadster Dual-Blower Upgrade Pics

This came up in the Extended Warranty Thread, but it deserves its own thread (hey Mods, want to move those posts here?):

Took my rear wheels off today, and sure enough, found a few leaves in the right hand side blower (left hand blower was clean). I guess it's good that the leaves were still in the fan and not chewed up and blown into the PEM (as used to happen). Anyway, here's some pics, including showing the new anti-sway bar:

From the left-hand side (US Driver's):
FanWithAntiSwayBar.jpg


OverviewNew.jpg



From the right-hand side:
RightSideView.jpg


I didn't take the rear pan out, so this was the best I could do for a view of the single motor between the two blowers:
MotorInBetween.jpg



BTW, here's what my PEM looked like at the last cleaning Tesla did:
PEM 1.JPG



I notice that the anti-sway bushings are rubber. In other cars, a nice upgrade was to replace them with hard plastic. Now, Roadster is already a pretty tight car, so perhaps this would just make the ride harsher, but has anyone thought about it?
 
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