1. Background: www.xcar.com.cn/bbs/viewthread.php? tid=97982510, a 10-year-old Corolla changes gearbox oil and gearbox filter elements to deal with water leakage in the trunk
Reason: Looking at the tailbox when it rains, the test paper towel is still wet, especially when there is water on the right side. You can still raise fish in the spare tire.
It is tolerable and it is intolerable!
2. Looking for various information on the Internet, either the sealing rings of the taillights are aging, or the sealing strips of the tailboxes are aging, or there is a gap in the buckle that causes water to enter, or the skylight water pipes have poor drainage, or the breather holes leak water.
Okay! Labor and capital sealed you all off, and you gang wiped out the streets, pulling fire from the bottom of the pot and serving with sealant.
3. Final result: After experiencing heavy rains in Guangdong, the problem of water leakage in the tail box has been completely solved.
1. Replace the right taillight gasket and two brake lights
Laoka right taillight gasket
Clean the right taillight and the sealing glass glue from last time
On the right side of the car body, there is also the sealing glass glue from last time. Clean up the glass glue and old sealing strips.
Also replace the two rear brake lights, Osram’s model 21/5W
Tear off the gum of the gasket, stick the glue side to the car light, and press the other side to the car body
2. Seal with glass glue
Replacing the right taillight gasket is quick and easy. However, in order to completely solve the water leakage problem, it is necessary to remove the plastic plate of the rear bumper to inspect the buckles and vent holes and glue them to seal them.
I chose to go to the auto repair shop near my home to disassemble and apply glue (mainly because the owner of the auto repair shop has a good character). It took an hour and a half, but the total cost was only ¥ 60. It was worth it.
Looking from the inside, a light rain found that the test tissue in the right vent hole (black plastic) was soaked (3 balls of white tissue), and there was obviously a problem with the vent hole.
When viewed from the outside after the bumper is disassembled, the vent sealant is aging and has water traces
Remove the right bumper fixing buckle plate.(upper left corner) The two buckles are connected directly to the inside and there is no sealing ring for waterproofing. This is the root cause of the common problem of water leakage in TNGA Toyota roof luggage rack nowadays. Opening holes are only fixed with buckles without good sealant sealing and water seepage.
On the right side, buckle holes, screw holes, and drain holes, all glue them before installing them to prevent water seepage.
The right bumper is fixed on the buckle plate (screws in the middle and no sealant seal). As expected, water leakage is an inevitable probability, and water leakage is a high probability.
Looking from the outside, on the right side, the buckle holes, screw holes, and drainage holes are all glued before installing to prevent water seepage.
Looking inside, on the right side, the skylight drain pipe holes, snap holes, screw holes, drainage holes, and rear car light snap holes are all glued before installation to prevent water seepage.
Although there is no leakage on the left side, the vent hole on the left side must be glued and sealed as a precaution (the wire is the reversing radar wire)
After this battle, it was verified by the torrential rain of Dragon Boat Water that no water traces were found in the tail box and no longer leaked water.
However, it was also found that the buckle of Tiumentan did not have good sealing properties (an absolute common problem), and there was a high probability of water seepage and water leakage. Coupled with aging, water leakage would definitely occur. Therefore, be sure to seal the roof rack and trunk buckle to prevent water seepage.
MartinWood 
5 
September 5, 2024 
