[xj40] Sunroof Drain Tubes, Front

My Left Front drain tube for the sunroof was plugged, with water standing in it. I tried compressed air, nylon trimmer cord, 12 gauge electric wire, fish tape and finally safety wire in an effort to break the clog.

When probing from the LF wheel well with the safety wire, I may have poked a hole in the internal tubing, as water began to drain from somehwhere about 6" BEHIND the drain tube (I have the inner wheel well liner which covers the atmospheric catchment tank @ rear of wheel well, & lower drain tube removed).

The line is still partially plugged (compressed air or blowing into tube has much more resistance than other 3 drain tubes. Even though the RF drain tube is open as far as air going through, there is some obstruction, right-angle, or chamber below the A-Post where the probe line cannot go all the way through.

Questions:

(1) Anyone know the configuration of the front drain tubes? The rear tubes are uninterrupted all the way to their end behind the rear wheel wells, so that nylon line passes through easily, but NOT the front.

(2) Is there any access to the drain tube at the lower/forward end of the A-Post? For instance, the air plenum beneath the wiper arm.

Thanks,
George Balthrop, Clifton, VA USA
85 & 89 XJ-S Coupes; 89 XJ40 VDP

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In reply to a message from GBalthropXJS@aol.com sent Sat 28 Aug 2004:

You’ve lost me totally here … are u saying we have drain tubes
on our sunroofs (and 4 of them?)??? I’ve never noticed them when
dealing with the panel. And the tubes runs all the way down and
drain at the four wheel wells?–
The original message included these comments:

When probing from the LF wheel well with the safety wire, I may have poked a hole in the internal tubing, as water began to drain from somehwhere about 6’’ BEHIND the drain tube (I have the inner wheel well liner which covers the atmospheric catchment tank @ rear of wheel well, & lower drain tube removed).

–
&:-)) Paul '88 XJ6 VDP 130k & '88 XJ6 VDP 180k
Garland, Texas, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

In a message dated 8/28/2004 11:37:40 AM Eastern Daylight Time, “AttyDallas” attydallas@aol.com writes:

are u saying we have drain tubes on our sunroofs (and 4 of them?)???

Yes.

And the tubes runs all the way down and drain at the four wheel wells?

Yes.

The front drain tubes are the 3/4" tubes which exit the wheel well directly behind each front tire. The smaller tube beside the sunroof LF drain is the atmospheric catchment tank overflow tube. The rear drain tubes exit between the front of each rear silencer and the sheet metal, about 6" behind each rear tire. You can see the front drains at each front corner of the sunroof assembly if you open the roof. The rear drains are much harder to see–you might have to remove the panel to see them. I have the headliner out (have recovered–hence the concern for staining the new material), so the entire sunroof assembly is quite evident.

If any of these four tubes is clogged, your top liner may become stained, particularly if your sunroof panel is not properly adjusted, or the seal is damaged.

My apologies if this comes through twice. I sent the original over an hour ago and it has not gone through the Jag-Lovers server back to me.–
George Balthrop, Clifton, VA USA
85 & 89 XJ-S Coupes; 89 XJ40 VDP

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

Since the response was so underwhelming, maybe no one cares, but just to close the thread with a solution, here it is.

The issue was a front sunroof drain that didn’t (drain that is :wink: Here’s what I found (I already had my entire interior disassembled anyway, including the blower out, so it only took about an hour to solve the issue):

(1) The front sunroof drain tubes attach over a metal tube about 8" below and in front of the A-Post. This tube and the attachment point may be accessed via a trapezoidal foam plug, about 8" wide, located outboard of the A/C Blower (on either side), high over the fuse box.
(2) In my case, the hose had a sharp bend (kink) in it (probably since original assembly, or maybe the dealer that replaced the auto seat belt track a couple years ago (under lifetime warranty) messed it up. The flat bend had effectively closed the tube so that it would not drain. When I probed with wire from the wheelwell side, it pushed the hose off the metal tube.
(3) The result is that if the hose gets pushed off the metal tube, you get some drainage onto the foam plug, with leakage onto the fusebox (NOT a good thing).
(4) If the hose does NOT drain, you get stain on your (new) headliner fabric (also NOT a good thing).
(5) Some metal/hard plastic reinforcement around the kink in the tube, to try to restore/retain the original circular cross-section should fix it.

Sometimes the simplest things can be the hardest because they are hidden. What I had estimated as a 20 minute job to clear the drains actually took 4 hours.–
George Balthrop, Clifton, VA USA
85 & 89 XJ-S Coupes; 89 XJ40 VDP

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

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Thanks George, invaluable information, hopefully I’ll be able to fix my leak now …I’ve been pulling my hair out trying to find the source of my wet footwell, had to go back to 2004 to find the ONLY description/layout of the sunroof drain assembly …will update when it warms up and I can get in there and investigate
…
Cheers and thanks again

Larry

Examining the area under the foam plug on a late model (94), the arrangement is slightly different - (surprise!)
The hose doesn’t separate at the metal union, so in effect, can’t be pushed off the metal tube :frowning: - hose is a one-piece tube running full-length from the sunroof through the metal sleeve under the foam plug aperture into the inner fender and out to the wheel well.

Drain tube hose emerges in fender well

view with fender removed, hose retracted

Was hoping to find a broken join, but no such luck, water continues to pool in footwell during heavy rain.

Found the problem.

The channel that drains from the windshield terminates directly above the metal sleeve that the drain tube passes through, which in turn is directly above the wiring harness that enters the car through the lower grommeted aperture. Water flows from the channel, on to the pass-through pipe and via gravity to the wiring harness eventually eroding the grommet seal allowing rainwater into the footwell.

This is a design fault and will eventually cause leaks in all cars - in my case I hadn’t noticed a problem until this fall when I lost my covered parking and moved the car on to the street.

I’ve tried re-routing the stream from the channel using a length of hose …this may work but if not I also cleaned out the grommet slot and applied sealant to the join.

Here’s a pic from another car that leaked in this way which eventually ate away the grommet aperture. There is no way that this area gets subjected to rust other than from water running down the harness from the ill-placed drain channel.

Really stupid design, Jaguar!! :confused:

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