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Roadster Rear Blower Maintenance

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And yes, it is louder than the original setup.

Agreed.

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

Um, right... probably should have split the blower discussion off already. I've merged it here and renamed the thread to be more appropriate to the discussion.
 
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:

...

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?

I'd put a screen over the intake of the blower. But honestly I'd try to run a duct up high to pull in cleaner air with a screen there too. I love glue guns! I'd just glue the screen mesh to the face / intake of that blower for a fast and ez solution.

As for the bushings, anywhere you can harden them up you get more feel and contact from the car to the steering wheel. But if you want a Cadillac ride you wouldn't want that, but hey, its a Roadster and ment to be driven that way. Otherwise its abuse! I replaced my rear control arm bushings with poly's for that Dietcshwerks showed me that there's a flaw in the Lotus design that causes the rear control arm to slap into the frame once the bushings wear and have a little give.
 
Sounds easier to monitor and address down by the blower.

Well, neither are easily visible nor accessible locations. Yes, the blower is easier to check/clear, but I think the dynamics is that it's better to push against a clog than to pull from it. Perhaps someone more knowledgable can respond?

My limited experience shows that the new dual-blowers seem to have different characteristics than the original 2.X blowers. Typically, it gets hot outside just before my annual service time, so we'll see if this year shows my PEM temps rising to yellow/red levels before cleaning.
 
It wouldn't be all that difficult to access the blower with the 2.0 mesh screen / diffuser, some canned air on an extended hose run. On a 1.5, 2.0, 2.5, taking off the lower diffuser pan isn't a big deal at all, especially in the day of electric drills and screwdrivers to aid in speedy assistance. Most of the leaves would fall down off that vertical surface anyways to the belly pan once the blower was shut down. If the blower ran backwards for say 5-10 seconds, paused, then cycled forward before each startup cycle then the blower would back flush itself. But that would have extra odd fan noises people wouldn't like.

After Doug mentioned about the Box, which Telsa upgraded the Roadsters living in the elements to keep the salt and corrosive elements out of the Blower, it does appear that this design is a step up in the design, where its pulling air from the top (that's open) of an enclosed box and has a lower chance of pulling in leaves and road debris.
 
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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.

I've been thinking ever since our first PEM cleaning back in 2013 that it was not smart to be drawing in dirty warm air off the asphalt and into the PEM so a few weeks ago my eldest son and I added an air duct from the driver side inlet down past the PEM and inner wheel arch to the fan housing.

marks iphone5s 356.JPG


In order to get only clean cool air into the fans it was necessary to build a shroud around the fans too.

marks iphone5s 360.JPG


We did all this and it certainly worked in so much as air was being drawn from the driver side air inlet very well, however the car complained that there was a cooling issue.

The issue went away when I removed the shroud so I guess they are testing the air pressure being acheived by for a specific fan setting.

I'm going to try some other ideas in a few weeks when things calm down with work but for now we do at least have a feed of clean cool air down to the fan area that is driven by the car's forward motion. Its just not the only place the fans get air from.

I can show you guys videos of me drilling the carbon fibre etc. if you are interested (a horrible experience!) :)
 
Excellent R&D !

Q: Based on @ PV4EV 's work on Aerodynamics, are you sure that those air 'inlets' actually have positive air pressure ?
It may sound like heressy - but they could just be for styling (especially as the exits holes / drilling are pretty small).

It may be worth looking for areas on the car which always have Positive air pressure ....

below is a pic I like:
aerodynamic2.jpg



I'll leave PV4EV to share his 'pressure' knowledge.
 
Cool info on the air pressure.

I suppose the vents were originaly for engine air intakes? Anyway, I'm not up for drilling the body anywhere other than those vents unless it is seriously justified.

That said, the main objective is to provide a large supply of air from cleaner areas and away from the hot asphalt without impacting aerodynamics and also considering water flow in heavy rain (don't think I want to be blowing rain through the PEM!). Glad to hear any suggestons.
 
@mgemmell What about, if you've not already done it, removing the black plastic liner in the vent to try and increase air flow ?
Or even also, add a clear plastic lip, along top edge of the vent to 'scoop' some of that fast flowing air in ??

I am following your work with interest as I completely agree that sucking up dirty air, and then cleaning the dirt out of PEM and motor cooling fins at annual service is .. well ... NUTS !!
Or maybe we can learn something from aircooled VW and porsche engines ?

I've got some air filter material waiting to close off the plenum chamber around the fans .. that is AFTER anual service to clear out dirt and dust.

PS the picture shows speed of air, rather than pressure - but its easy to deduce high pressure areas (eg front air intake).
also see this post from Dash in UK ... Hi All from Oxford, England, UK - F1 inspired parts anyone?
 
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The first thing that came to my mind was: create a scoop on top of the inlet, and take out the cheese grater on the inside of the intake, so I guess our minds are in sync Mark ;)

I did a quick mspaintjob to illustrate what I mean. Orange is the current inlet. In red, is your tube trajectory. I drew a scoop on top of it. I've seen it working with VW's (both aircooled and watercooled ones), this will give you more intake pressure: for sure

Untitled.png



To test it, you can improvis by taking a coke bottle and sawing off everything that's not inside the green box below:

bottle.png


Some masking tape should be enough to mock up a working intake!



Edit: Also... when it comes to rain, that's an easy fix.
In the past I made this ram intake on my VW Beetle:
8q1b.jpg


I was afraid of water, because it was a closed system. I added a one-way valve at its lowest point, in such a way that it was closed when the intake was under pressure, and open when it was resting. It would only become a problem on longer trips when the valve would be closed for a longer time.
 

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About one year ago I wrapped the blower fan of my roadster 2.5 in "Gutter Guard" (see PEM / Motor cooling fan filter). So far, I have not had a recurrence of leaves being sucked up into the blower fan.

Great idea for leaves, but what about the heat? Around here (central California), summer ambient air temps can top 110 F, and "freeway", a term intended to refer to the Interstate highway, more often than not describes a parking lot. With the black asphalt of the road absorbing sunlight from that fusion reactor in the sky, you have inlet air temps under the car well in excess of that 110 F, with very little forward motion of the car.

Is there a cooling stage before the air enters the PEM? I know the car can use the A/C to cool the battery, but I didn't think there was anything between the blowers below the car and the PEM electronics module. If that's the case, then drawing air in from above would be a really good idea. Is there any space to put a second set of fans to draw air in from the top inlets, and throw it at the blowers below? Just a thought.
 
I added a "filter" to both sides of the bottom pan and attached via Velcro. I made it out of the corrugated plastic and painted it black so it would "disappear". It seems to do a good job in keeping leaves and other large junk away from the bottom blower.
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Was the upgrade from two separate blowers to a single, larger blower and upgraded sway bar free for all the 2.0s? I looked under my car and realized that I still have the two single blowers. Can I ask Tesla to install the upgrade in my car? Does it really improve cooling a lot?
 
Was the upgrade from two separate blowers to a single, larger blower and upgraded sway bar free for all the 2.0s? I looked under my car and realized that I still have the two single blowers. Can I ask Tesla to install the upgrade in my car? Does it really improve cooling a lot?

It improves cooling significantly. A bigger difference was the snow dam that greatly reduced (but didn't eliminate) the amount of debris that was picked up in the fans such as leaves. It also protected the motor/fan bearings from salt and water corrosion. Those bearings are a frequent source of failure. It was free for the vast majority of people they did it for, but they didn't offer it to everybody. Tesla's policy was not always consistent. Generally, but not as a rule, they offered it to roadster owners living in places where it snowed and/or they salted the roads. The policy was not very good IMO because there was no predicting where a car might end up. What if you moved from Texas to Chicago after your warranty expired? Or sold your So Cal car to somebody in MN? The MN buyer would have to pay to have snow dam + sway bar + new fans retrofitted if it was out of warranty.
 
Was the upgrade from two separate blowers to a single, larger blower and upgraded sway bar free for all the 2.0s? I looked under my car and realized that I still have the two single blowers. Can I ask Tesla to install the upgrade in my car? Does it really improve cooling a lot?

Was the upgrade from 2 to 1, or 1 to 2? With my recent PEM alarms, the SC verified that my 2.0 (#834) already has the upgrade, and there are definitely 2 blowers under the rear of the car.
 
I looked under my car and realized that I still have the two single blowers. Can I ask Tesla to install the upgrade in my car? Does it really improve cooling a lot?

Take a look upthread at these pixs of the singe motor/dual blower upgrade. Does your setup look like that??

Tesla probably won't do the upgrade unless you've had significant cooling issues that they're not able to address in other ways.