KahnBB6

iTrader: (5)

I see fairly frequent rainy weather where I live and the SC has recently developed what appears to be a clog at the sunroof drains which allowed some water intrusion. Specifically the driver's side rear sunroof drain. It ended up damaging my rear passenger seat bottom on that side and corroded the connector on a body harness just under it.

I removed the rear seats and extensively deep cleaned and wet-dry vacuumed the whole interior. I also looked up all the male and female terminals for the connectors in that location and just ordered $400 worth of OEM repair terminals to fix those wire by wire. It's a shame because I was just going to have time to test a newly re-capped engine ECU and get the car running again.

The interior is okay again and no cosmetic damage occurred other than the lower rear seat cushion. I guess this is the motivation I needed to finally get the rear seats reupholstered in new leather to match the restored front seats.

For now with no garage I am covering the top of the roof with a waterproof tarp with some soft weights on top to keep rainwater away from the sunroof.

I will be able to finally garage my SC in the near future to keep it out of the rain but not before needing to solve the current issues.

Hopefully an additional issue isn't the rubber sunroof glass seal going bad... because Lexus doesn't even have a part number for those. Just the entire piece of sunroof glass with rubber weatherstrip seal only.

...

After discovering wetness in the headliner it is clear that all four sunroof drain holes/lines need to be vacuumed out and cleared with weed whacker line to unclog them.

See this diagram from the SC300/400 TSRM. The front sunroof drain holes are very easy to access but the rear drain holes are very far back in the assembly.





Does anyone have any good method for successfully getting a vacuum and weed whacker line into those areas to clear them out?

It looks to me as if it will be difficult from the top of the car. There is a TSRM procedure for removing the head liner which would allow access to the drain lines from the inside... but this is a lot of work.

How have you all managed to clear out ALL FOUR SC300/400/Soarer sunroof drain lines without damaging them?

...

Honestly this is all motivating me to determine a long term plan to take the car or a donor SC roof to a master metal and body person to have the sunroof hole welded up with sufficiently thick and high quality steel... to eventually turn the SC into a custom non-sunroof slicktop.

I have never cared for sunroofs and this is a big reason why.

.....

Edit: After speaking with Gerrb about this I think my approach will be to *attempt* to vacuum the sunroof drain holes at the rear from the top of the car with some kind of small wet-dry vacuum with a tube that has a long nose and then my primary approach will be to remove interior pieces to partially drop the headliner in order to access those rear drain hoses from underneath.

And I'm going to order new OEM metal clamps for the plastic hoses to have on standby just in case.

Worst case scenario I'll follow the TSRM procedure to remove the entire headliner from the car temporarily in order to thoroughly clean out each sunroof drain line.

Unfortunately I'm waiting on the electrical harness OEM repair terminals until early December so that will be a later project. In the meantime I'm going to make up my wiring pinout chart (to have on hand for safety) following the factory wiring diagrams in preparation for that.

t2d2

iTrader: (8)

I've tried a few times, and as far as I can tell, it's 100% impossible to get to the rear drains from above, with the sunroof assembly in the car. Other people say it's doable, but I refuse to believe it until I see it... I've spent hours trying to locate them by feel, being totally blind access.

It's not too tough to locate where the drains exit down below, so pushing something stout yet flexible up that way is probably a better bet. Then just vacuum anything up from the sunroof tray that gets pushed out. I think I tried that method once and didn't have much luck there, either. The typical weed wacker advice is simply not suitable to the task. It needs something closer to the stiffness of solid core copper wire, but somehow soft enough to not damage the drain lines.

The lines are easy to get to with the headliner removed, and probably no need to drop the sunroof assembly itself at that point...

I don't see how any vacuum attachment would fit back in the tray to reach the rear drains.

KahnBB6

iTrader: (5)

Thank you t2d2. I was going to at least attempt some cleaning from above but will not waste my time based on your advice above. I'll focus entirely on getting the headliner at least partially dropped... or fully removed and then focus on getting the rear lines serviced from inside the car.

I'm definitely buying OEM new drain hose clamps.

The front two drain lines I'll tackle before I get into cleaning out the rear drains. At least with those I know I can get to them extremely easily to clear out.

t2d2

iTrader: (8)

Can't hurt to have new clamps on hand, but I wouldn't expect them to be a failure point. They're just typical spring clamps, as I recall.

BTW, I think I also tried blowing compressed air up from the bottom of the drains. I don't know whether or not it worked (should have had a helper up top to detect movement), but no wad of gunk came out. Then again, I don't know that I actually had an obstruction in the drains. The only time I had an issue was when pressure washing the car, since I needed to clean it off after doing the driveway and splattering stinky "pond scum" everywhere, and didn't realize that doing around the sunroof was more than the seals were meant to handle. I got a bunch of water inside, like what you experienced.

Now that I think about it, I wonder if the drains were ever actually the issue? It might just be the design of the sunroof tray and how much water it can handle before it spills over, since there's not really a good path back to the rear drains. In which case, your desire to make it a slick top is probably on the right path.

KahnBB6

iTrader: (5)

I am going to try to disconnect the rear hoses to work with them and the sunroof tray from there. The clamps are still available so I definitely want a set on hand just in case the original ones happen to present as a failure point... but I have my doubts as you do.

I think in my case some very heavy Florida rain through the middle and latter part of this year is what caused this. However this SC has been through many heavy rainstorms over the years and has never had a sunroof leak in this way.

As for my wish to turn it into a slicktop with custom body work... that will take much longer if I can get it arranged but I am considering some long term options to make that happen. All of them involve welding metal in one way or another rather than fabricating a plug out of fiberglass or carbon fiber.

For now I've got to do what needs to be done to fix the sunroof leak and get it to drain correctly again.

My GR86 has no sunroof, never had the option of one and I couldn't be happier with that since there will never be anything up there that will leak.

Bimmerbill

Craig,
I may have mentioned this before but I agree the weed whacker line does not have enough substance to do any good on the drain holes. A number of years ago I purchased a piece of small cable from Home Depot to run through my lines on my BMW. This cable is smaller than the ID of the drain tube. I wrapped the end with tape to cover any sharp ends. As many times as I and friends have used it the tape is still there. A long time ago speedometer cables (when cars still had speedometer cables) were recommended but you could not find any long enough. If you elect this route make sure you buy a piece of cable long enough.
Good luck,
Bill

t2d2

iTrader: (8)

This probably isn't the approach you're after, but it did work quite well and is a lot less work than a seamless fab job:

https://www.clublexus.com/forums/bui...ml#post9668899

You could even view it as a temporary solution, as filling the rivet holes -- or just cutting them out along with the superfluous lip -- probably wouldn't be any extra work when the true fab work is performed.

GAsc300

Kahn

i think it’s possible to clean these rear lines with stiff small diameter wire and MAYBE with weed whacker line, but you gotta thread carefully and get lucky that you get into the rubber tubing. Home Depot has spools of wire and rubber coated wiring of various diameters that helped me… get at least 4 feet (maybe 6) if you want to extend all way through to bottom drain line exit points. That’s assuming they are clogged and not disconnected. When I dealt with mine leaking through headliner, one rear was clogged, the other drain tubing was disconnected completely from sunroof assembly.

From another post by me …
The rears drain holes are back there in the rear corners of sunroof housing but can’t be seen so can’t easily be cleaned. This time I was determined to see the rear drain lines. I sat in the back seat and pulled the headliner off it’s rear clips to do so.
I observed that the back of the headliner is held onto roof with plastic clips (4?) that fit into slots in the metal roof. These are about 2-4 inches from the back of the headliner. The clips are attached to thin metal brackets that are glued to headliner. So the headliner isn’t glued directly to roof, but rather, held in place by these clips plus some aluminum screen things toward center of roof that act like Velcro. I only took off the rear clips and messed with the first 10 inches of the headliner.

When I got the back of the headliner unclipped from the roof I could see the back of the sunroof housing and the rear drain lines. It’s a tight fit in the back seat and my photo is too close up but that’s all I could do. See below:


I’m sitting in rear passenger seat lookin up at roof after pulling headliner back. In this photo I have disconnected the rear drain line and have a metal wire running through it. My car is maroon and you see the bottom of my roof, rear part of the black plastic housing of the sunroof, and the disconnected drain line that starts here and runs downs 4 feet or so to drain out behind the passenger rear wheel, technically exiting out of a tube in the rear quarter panel behind the wheel.

My passenger side rear line was clogged and my driver’s side rear line was disconnected completely. So when the rear driver’s side line drained, it drained into the back of my headliner. For how long, who knows.

here is a photo of where the rear drain line exit the car being the rear wheel:


This is behind my rear driver side tire looking up under the rear quarter panel (if that’s technically the name of the piece). In the lower left you should see a rubber tube and inch or so long. This is where water exits from the rear sunroof drain line. The drain line tubing attaches to this rubber tube on the other side of this panel. Possibly you could attempt to unclog the rear line starting here and going up with a wire but that wouldn’t tell you if your upper line was disconnected as mine was.

GAsc300

And some after market vendor sells sunroof block off plate for SCs that *might* help you and be easier than method you were theorizing regarding sealing off sunroof.
Check out:

https://lrbspeed.com/product/sc300sc...-delete-panel/

Bimmerbill

Great pictures, and a lot of information. I see you are using the small cable that I had suggested to Craig. I did wrap the end with electrical tape to cover any loose wires. I would also recommend a minimum of at least six feet of cable when purchasing. Also I did not realize that the headliner could be pulled down that much with out damage.
Have a great day,
Bill

t2d2

iTrader: (8)

I didn't know anyone was offering that ready made, but I would caution against ordering it as listed.

"Panel is 2″ larger in each dimension than the opening for the roof in the chassis’s body, and comes pre-drilled for all the fastening rivets

(EXAMPLE: If your sunroof opening measures 32″ x 24″ the panel we provide will be 34″ x 26″)"

That's not enough overlap, IMO. I did twice as much (2" all around, instead of 1"), and don't feel halving it would adequately clear the channel or provide enough rigidity.

KahnBB6

iTrader: (5)

GAsc300,

Thank you VERY much for those pictures and the writeup! That is exactly what I need in order to form my plan of attack!

I have an automotive boroscope camera with an LED light on the end of it and a small standard definition video monitor. I have used this many times in order to see what I am doing with very tight and otherwise impossible to see areas of the engine. I have thought that I may use it to first find the deeply recessed drain holes at the top of the sunroof.

But I feel that between Gerrb's, yours and all other advice here the head liner drop method will be what I go for primarily to access those tubes. I would certainly hate to find that one of them has been disconnected as yours was. There is nothing to yank on those tubes from inside the car so I wonder if it had to do with shrinkage over time or perhaps the metal clamp having lost tension (hence why I am ordering a new set of them just to be safe).

I've removed my rear seats already so I would be sitting/crouching just on the underlying metal surfaces.

I will also find the lower outlet drain tube and try my luck with cleaning it a bit from below. Hopefully that wouldn't make the clog worse.

Gerrb mentioned that the drain tubes have a sharp bend downward somewhere but I cannot see that in your photos. I assume this would be at the top of the pillars at the rear windshield.

KahnBB6

iTrader: (5)

I am aware fo the LRB Speed aluminum panel that is marketed as a sunroof delete. However this is a very crude solution to me. I think it's fine for a dedicated stripped down and fully caged track car but not for a clean street car. I don't want rivets in my roof with a visible panel. I want a totally smooth painted roof with metal welded in matching the same contour as the rest of the roof. And with a slim center support underneath to replace the strength that the sunroof assembly provides. Factory slicktops have this center support metal underneath on the inside.

The approaches I am thinking of is either to:

1) Swap over the entire roof panel cut out from a wrecked and mangled impossible to re-register junkyard hardtop SC/Soarer (which will be damn near impossible to find).

2) Go to a junkyard which has an SC that has a sunroof top, cut out the entire roof section with some of the lower rails below, then de-weld and take that part to an expert welding and body guy to have sufficiently thick steel panel formed up and tack welded many, many times all around and then ground smooth before filler and other work is done to prepare the surface for paint. And have a center support structure added underneath similar to where all hardtop SC/Soarer slicktops have it.

3) The same procedure above in #2 but instead take the entire car to a body shop that can do on the existing sunroof top metal that it came with. This would be done at the same time I would have the whole body prepared for new paint.

All of these are very involved. I know every step of what needs to be done... but I am not a welder or body guy and don't trust myself doing the work so it would have to be taken to a professional who knows what they are doing in practice from experience.

Here are some examples of how this is done:


The first examples are of swapping over a slicktop roof from a donor car.







The second is how you form up and weld in a metal panel before paint on a sunroof equipped roof.



This third video is a much better version of what *should* be available for sunroof delete plugs for these cars. I don't want to do this but this is far superior to the rivited LRB Speed roof panel for stripped down dedicated track cars. You'd think that by now one or more companies would have offered a fiberglass or carbon fiber plug kit like this for SC's and Soarers given how many of them are set up as high powered drift and track cars. BMW E30's and E36's also have these options available. But for whatever reason SC's and Soarers do not despite their popularity with tuners.

And as you can see at the end of the video... even this ST185 Celica All-Trac owner eventually decided to find a base model Celica slicktop in a junkyard and cut the entire roof panel off of it to use as a donor to swap into his factory sunroof equipped model.

t2d2

iTrader: (8)

The boroscope approach sounds like it has potential.

Turbostar

I'm not sure that picture you took of the tube is the actual sunroof drain tube. I've messed with mine extensively (see my post history), and that tube looks like the trunk drain. I'll take some photos of my own when I get home, or perhaps it is different on the 1993 model.

For mine, when I was testing sunroof drains, I used a turkey baster and put water down each hole individually to see how they drained.

When I put water into the rear holes, the exit is actually in front of the rear wheels on the bottom of the rocker panel. The tube exit has a screen or grate piece over it to keep stuff from going back up.