After spending over 200,000 yen to replace the speakers and deaden the doors, the next step was to repair the faded cowl top and deaden the bulkhead at the same time.
Even after searching online, I could not find any information on how to disassemble it, so I am writing this down as a work note.
Remove the wipers
Once the wiper position is recorded, remove the wipers.
Just loosen it with a 14mm bolt and then twist and pull.
I recommend putting the nut back on.
Remove the cowl top panel
The rubber molding that runs from left to right has several holes drilled into it, through which rods can be inserted on the left and right.
It can be easily removed by grabbing the hole stopper and pulling it to the right or left.
First, remove it from the panel that is removed when changing the brake fluid.
It’s only held on by two clips, and if you just pinch it and push it in it will come off easily.
When you lift it up, the clip should come out with a loud noise.
Next, use a flat-head screwdriver to remove the two clips that secure the cowl top.
Things are going to get difficult from here on out.
First I want to remove the small panel on the top side of the cowling, but to do so it looks like I’ll need to peel off the bottom tab of the glass side molding(?).
Close the hood and carefully peel off the tabs to remove them, being careful not to scratch anything.
The difficult part comes after this.
The windshield and the cowl top panel are held together by an interlocking L-shaped, horizontally long piece, so the seam needs to be peeled apart.
It feels like the glass and panels might break at any moment, but we proceed carefully, one unit at a time.
You’ll come face to face with the hidden dirt that has accumulated over 10 years and 150,000 km.
I washed it by spraying water on it with a hose, but there is a risk of rust due to the hybrid system and water accumulating, so do so at your own risk.
Remove the wiper motor
Although the wiper may look complicated, it is actually easy to remove by removing two bolts and one coupler.
There are two 10mm bolts on the left and right. First remove these, then you can pull it out by twisting it diagonally to the right.
Please note that the back part is hooked horizontally into a hole. When you put it back, you will insert it from this hook part at the back, not the bolt.
The coupler can be easily removed by applying force as shown in the image.
This black panel also seems like it could be easily removed by removing the bolts, but I decided to leave it for now.
Sound deadening
Bulkhead deadening
The 50 Prius bulkhead is recessed and has a complex shape with metal seams and ripples.
Basically, we will be installing Audio-Technica damping absorbers.
This product is a combination of vibration-damping material and sound-absorbing sponge.
But it’s impossible to stick it to small areas.
comes in That’s where E-140 vibration dampening spray .
This an undercoat spray that also functions as a vibration-damping material . is
The liquid can reach even the small areas where vibration-damping material cannot be applied, so it was extremely useful when deadening doors.
If you replace it with an extension nozzle like the one below, you can insert the tube into the round hole and apply the liquid. It has the double effect of rust prevention and soundproofing. I recommend cutting the tip at an angle.
The opening on the side allows a little access to the inside of the fender. The area where the vibration-damping material can be applied is limited, but with E-140 spray it can be applied all the way to the back. I plan to do a proper deadening of the inner fender at a later date.
Deadening of cowl top panels
First, we attached the Audio-Technica damping absorber, which has both vibration-damping and sound-absorbing effects.
You should install each piece on the car and check that it does not interfere with other parts . I stuck them on too much and they didn’t fit in the end…
As a final touch, I applied a brush-type undercoat material with vibration-damping properties on top of this.
Since the material is made of plastic which doesn’t resonate that much, its effect is little more than a charm, but it’s better than nothing.
Actually, I bought it to paint on the undercarriage and wheel housings.
I bought a brush to make it easier to apply. If you only need a little, you can put it on a glove and apply it.
return
Put the wiper motor, cowl top, and wipers back in place.
Maybe it’s because of the sound absorbing sponge, but the cover for replacing the brake fluid won’t fit anymore…
It looks like a luxury car! The unexpected effect of bulkhead deadening
The sticker wasn’t applied perfectly, and the E-140 spray was only applied to an area no more than a few dozen centimetres above and below.
I didn’t have high expectations, but the changes were greater than I expected.
The car’s ride quality has obviously improved, and the interior atmosphere feels more like a Lexus.
Overall, the interior of the car is quieter while driving.
The engine noise became less chaotic and more gentle, like that of a luxury car.
The whining sound of the motor or inverter has also become quieter.
However, it is ineffective against the rattling vibrations caused by rough road surfaces.
There is a reason why I’m using studless tires…
The part of the Prius that needs the most sound insulation is the wheel wells.
For some reason, the way the audio sounds has changed, and it seems like there is a crunchy sound in the high frequencies.
The equalizer needs to be re-adjusted.
I plan to get the job done after I’m soon going to deaden the wheel wells and hood, apply vibration-damping undercoat to the undercarriage, and change to summer tires, Regno.
