Check Sunroof Drain Tubes periodically

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May 9, 2003
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This is something anyone who owns a car with a sunroof should do occasionally, esp if you park outside under trees a lot: check to make sure your drain tubes are not obstructed. (slowly pour water down the drain tube openings on either side of sunroof "tray" test, to see if water drains to outside of car, as it is supposed to) If drain tubes are clogged, water WILL find its way into the headliner, A pillar and if the clog is further down, expect a very wet carpet and floorpan. One may not notice this in time, unless it is after a huge rainstorm where the amount of water is hard to miss inside the car - otherwise it happens SLOWLY overtime, while mold and nasties can be happily growing without you knowing. - Clean the sunroof "tray" occasionally, make sure it is free of debris. It seems most people who chase a leak in their cars hardly ever think of this as the cause, and even professionals don't think of it much. IF drain tubes are clogged, and don't pass the "water test", one can use weed trimmer line, or a speedometer cable (from a kit, with unfinished ends) and as a LAST resort, compressed air. (I had success with weed trimmer line 0.095 size, and warm water - and luckily I noticed the 1st signs very early on after several days of heavy rains, which show the signs quicker). READ THIS: (The article contains a video about on how bad this can be) Damage From Clogged Sunroof Drains WATCH THIS:
 
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illinois, usa
You also need to pay attention to the cowl drains that are by the wiper motor. You either have drains on booth sides or the metal slopes to just one side. In my 98 Volvo, it has a drain in the passenger side that clogs and water enters the car by the air intake above the fan.
 
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When I bought my wife's Outback, I learned on the SubaruOutback discussion board that this is a common problem. So I adopted a PM procedure of shooting a mixture of hot water and heavy duty cleaner, such as Simple Green or Purple Power, down each of the four sun roof drains. I use a 60 ml veterinary syringe with a short length of 1/8" id x 3/16" od tubing on the end. This tubing fits perfect in the sunroof drains on the Outback. The rear drains are typically quite hard to reach. So for them, I used a stainless steel stiffener from a used windshield wiper blade, and heat shrink tubing to attach a length of the same tubing. This makes the tubing stiff enough so I can guide it into the rear drain holes. For cleaning drains that are already plugged, many use string trimmer line to push down the drains. String trimmer line is stiff enough that it can easily be pushed down the drain and push any debris out of the way, but flexible enough to bend with the shape of the drain. I am planning on starting to use the string trimmer line even for my PM. I'll just need to modify my tool to guide the string trimmer line into the rear drain holes.
 
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Feb 14, 2017
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Michigan
On my 06 Range Rover Sport i blow out the front drain tubes every month. If i get lazy I'm soon reminded by the swimming pool on passenger side floor. These Rovers are notorious for this.
 
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Daytona Beach
Quote
On my 06 Range Rover Sport i blow out the front drain tubes every month.
Not a great idea to use compressed air. You run the risk of blowing the line off of the connection fitting inside the roof, THEN you will have problems!
 
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My wife had a spider and web in one of the drains in her old Malibu Maxx. I used a syringe and the dude popped out the drain (inside door / fender area). Didn't expect to see him.
 

97tbird

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LAZYDOG: Thanks for the tip re: cowl drains - I was planning to remove the "cowl" and clean the area underneath- that piece is badly sun-faded and needs detailing, anyway - prob easier to detail out of the car. Re: Methods: I also used a syringe and tubing when I was "de-clogging it" using the trimmer line. I used hot water in the syringe to "squeeze" into the tubes, at the same time wiggling the trimmer line - worked really well. I had compressed (not regulated) air ready but will only have used as a last resort - I was also afraid of dislodging the tube inside the A pillar. Not sure about harsh cleaners like degreaser down the drain tubes - I am afraid they can be bad for the rubber tubes in the long run, I guess you can always flush with plenty of soapy water after using them? I was able to clean the sunroof "tray" really well (the area between the 2 drain holes). This is where all the pollen/dust/leaves and crud collects which eventually make its way to one or both drain tube openings. Keeping this area clean and waxed is important: it will make it harder for crud to "cling" to that area, and the water will flow easier to the tubes without sitting there. I am going to make the Trimmer line feeding and cleaning the sunroof tray area maintenance item part of at least a 6-monthly routine.
 

97tbird

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I say weed trimmer 0.095 weed trimmer line (about $6 at Lowe's) or if you need something a bit thicker: Speedometer cable (with non-terminated ends; if you get a "kit" from AZ or AA you can get that, it's about $6). I have read some use "fishing line" but i have no clue which one to get - I just went with weed trimmer line and had a speedometer cable as backup. I'd guess for most cars you'll need at least 5-6 feet to be safe. These 2 "tools" seem to be the most popular and successful at this job. (I feel like I read everything on the www when I needed to do this LOL)
 
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florida
this is my first and last car with a sunroof. drain is clogged on one side and requires the wiper cowl to come off to access it.
 

97tbird

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Originally Posted by super20dan
this is my first and last car with a sunroof. drain is clogged on one side and requires the wiper cowl to come off to access it.
Yeah I never WANTED sunroofs either - they just had them on my 2 used cars (BMW and the Ford) - on wife's Mazda bought brand new, we were able to "escape" it. Which car is that you have to take the wiper cowl off? Most cars route them through the A pillar and onto the fender behind front tire. Have you tried de-clogging from the top of the sunroof? Removing cowl requires removing the wipers, of course. Like stated in this thread, I am going to check the under-cowl drains on for clogging today on the Escape. Although the sunroof drain tubes are now free and fixed, i want to eliminate all possible leak areas before car goes tested in a heavy downpour again. I have seen YT videos where people remove wipers without the tool, and just by wiggling and pulling them off. Hopefully that works, if not I will have to go to Adv auto and get a wiper removal tool.
 
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Middle Tennessee
I have to do this on my wifes 2016 Nissan Rogue with the panoramic sun roof. The front driver side will stop up and get the carpet wet. She is not a happy camper when this happens. I run some trimmer line down it followed by compressed air. Hasn't happened in a while.
 
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Pittsburgh,PA U.S.A.
There is a YouTube video showing cleaning the back drains by removing the trim around the back wheeels and feeding a wire up the drain tube. For some vehicles this is much easier to access than the top of those rear drains.
 
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May 7, 2020
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Ames, IA
Our NewBeetle sat outside under a tree for a couple years when my sons’ wife had it. Now it’s mine, and I found the drains full of mud. I had to pull the A pillar trim to get to the connector to pull the hose apart and clean it.

Regular soapy car washes helps as well. I never had an issue with my Rouge or my Camry, but they are also garaged.
 
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