Where does the PEM fan get its air from?

[Carbuilder]

Being the curious type I took the rear plastic pan off the bottom of the car to check out the blower. Everything looked pretty good (but I cleaned the connectors and re-Deoxit'd them). But with the pan on it looks like almost a sealed compartment, so where does the air come in for the blowers? Obviously I'm missing something.

Rick

 

[Stefan T]

From the wheel houses
and from rear
but it will on came from rear then the speed is high enough appx over 100 km/h [62mph]

 

[gregd]

Being the curious type I took the rear plastic pan off the bottom of the car to check out the blower. Everything looked pretty good (but I cleaned the connectors and re-Deoxit'd them). But with the pan on it looks like almost a sealed compartment, so where does the air come in for the blowers? Obviously I'm missing something.

Rick

Looks like there was a pool of water in there at one time, judging from the white stains on the fan housings... Any idea of the history there? You don't want the PEM and motor to become water-cooled.

 

[dhrivnak]

Now that said for the 1.5 the PEM gets a good bit of cooling air fro the vents behind the drivers head. I think this is a big reason the 1.5 cars stay a lot cleaner.

 

[Carbuilder]

From the wheel houses...

No. If you look at the picture you’ll see that the snow shield (I think that’s what it’s called) blocks that area off completely from the wheel area.

 

[ML Auto]

You have the updated single fan unit with the snow shield. It just gets its air from around the gaps at the edges. Probably not good for PEM temps, but thats what they did. The original one didn't have snow shield to obstruct the air, it just vacuumed the road as you drove.

 

[Carbuilder]

I decided to have another look at this and improve it. There is so little space for the air to get in to the blower that it can't be good, even though my temperatures were OK.

You can see from the side, if you picture the lower plate in place it is almost sealed. There are some small gaps that I can't even stick my finger in. The blower must be struggling to get air. Since many of the cars don't have this shield, I could just remove it but I think it is a good idea to give the blower some protection. So I cut some holes in the sides and opened up the clearance at the back. This way the holes don't lead directly into the blower so debris isn't aiming right at it. The air can flow in/out through the side holes and the clearance at the rear to allow the blower an easier time getting air.

 

[X.l.r.8]

Looks like there was a pool of water in there at one time, judging from the white stains on the fan housings... Any idea of the history there? You don't want the PEM and motor to become water-cooled.

It’s djp’s Car, garage queen, but like all Toronto cars, driven in snow and salted roads.
Probably residue from winter driving. I’d hate to see mine!

 

[Marius]

After installing the JdeMo unit there was no place anymore for the snow shield, so I am driving without this. Almost no snow in NL which is probably why I did not get any issues with that removal.
On the other side. Today we got a heat record of 40,7 degrees Celsius in the Netherlands and I had a long drive today of 450km. Max temp of the PEM was never higher then 48 degrees Celsius meaning the last blue barr and the motor always stayed on the second blue barr which I find amazing.
Side note is that I came home and can not charge because of isolation fault #286. So I let it rest for a few days to cool off and hopefully it will refind itself.
The only issue is the battery which the airco could not get below 40 degrees Celsius and sometimes overheated in the first yellow barr.

I also noticed that after renewing the PEM
/motor cooling fan last year it seems that the speed of blowing increases with higher temperatures. Almost if the blower is temperature depended? Did not have that with the original coolar fan.

 

[hcsharp]

I also noticed that after renewing the PEM
/motor cooling fan last year it seems that the speed of blowing increases with higher temperatures. Almost if the blower is temperature depended? Did not have that with the original coolar fan.

The new fan has multiple speeds. The speed is chosen based on cooling demand (temperature). I thought the new fan was quieter at first but that's because it mostly runs at lower speeds. When things get hot it's actually louder than the old fan but also moves a lot more air.