Where's the A-Pillar Drain Hose Located?

I think someone (Kirby?) mentioned in an earlier thread that we do have a drain hose that runs down the A-Pillar to the outside of the car, near the bottom of the engine compartment (one other member I think said he thought it was somewhere near the headlights). I assume this also applies to the face-lifts, like my Superblue. Seeing that we are about to have flooding rain conditions here overnight, I looked in desperation for this hose to see if I could clear it out (using my patented guitar string method :smile: ) – I don’t want to wake up to a puddle in the front of the driver’s floorboard and a soaked mat AGAIN. However, after looking up and down the pillar I could not spot the hose or its opening, even after pushing the rubber door seal back a bit. Please tell me we don’t have to actually r/r the door seal in order to access the hose and its opening, knowing what a royal PITA it is to replace the seal in its mounting groove. :grimacing:

I take it you are worried about the drains for the sun roof? If so then the drains are positioned in each corner of the roof aperture AFAIK

No - it’s a face-lift 4.0, no sunroofs …

Then I don’t know where/what you are trying to drain?

1st photo from google THEY MUST BE somewhere easy as these ones were blocked and they guy told me if the p.o. had cleaned them out regularly it would never have happened, on the pre face lift the water runs down the inside of the chrome windscreen surround and out under the front fender485 DSCF0503


No doubt this info will be repeated over and over again

There’s no hose in the A-pillar, the entire A-pillar is the drain! There are gaps at the forward corners of the roof that feed into the A-pillars, and from there the rainwater flows down into the door jamb. There’s a deflector in the door jamb right under the lower end of the A-pillar that turns the water flow forward and around the front edge of the door.

There have been problems in which the A-pillar was found to be blocked with silicone sealant, which can cause the rainwater to back up and find another way to go, typically into the footwell. The stainless steel trim on the A-pillar must be removed by grinding off some pop rivets, the passage cleaned up, and the trim reinstalled – usually with stainless steel screws instead of pop rivets. On my '83 there were already stainless steel screws there, a sure sign someone had been in there before me.

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Thanks for chiming in on this, Kirby. So that means there must either be some of that silicone sealant blockage you mention (but why would someone use that there?) or my deflector is missing/damaged. :thinking: I’ll try checking those out … btw, before the rain set in this weekend I had recently tried using some silicone lube spray on the driver’s window channels (inc. the cheater plate) and outside of the door seal to get the window moving again w/o resistance and squeaks/groans. Funny thing is I noticed after day 1 of the rains there didn’t seem to be anywhere near the puddling on the floor mat/saturation of the undermat as there usually would be with such a deluge. Is it possible the coating of silicone lube is somehow diverting or “encouraging” the water flow back into the route that it is supposed to be following? :confused: If so, that’s a pretty simple and cheap hack that I wish I had known about and tried many years ago with Superblue!

Are you saying that the silicone coating may have swelled the door seal to make a “water-tight” fit - would be great if this works.

That could be a possibility … We have had soaking rain here for the past couple of days … I’ll see how watertight the floorboard is in the a.m… :thinking: If it turns out it didn’t do the trick, you got me to thinking about something … Isn’t how those power steering fluid stop-leak products work (as well as engine oil stop-leak) is that they cause the (rubber) seals to swell up a bit, back to near original tolerances? If so, I wonder if rubbing the outside of the door seal down with one of those products might do the same thing for it? :confused:

Just checking with you AttyDall to see if you were able to hold the water at bay during your last rainfall - Tex Terry II 1991 XJX V12 Classic Coupe, 1986 XJS V12 Coupe - 2/4/2020 1929hrs EST.

We had another round of rain just yesterday, and although there was some “seepage” onto the mat (I use a plastic aftermarket one on that side of the front, btw, to keep the underlying carpeting from getting wet!) it looked to be about 1/2 as much as usual. :relieved: I would therefore think the silicone spray and/or rub down with engine oil stop leak helped some by either swelling the old seal back up a little or making the rain run “faster” down to the path it is supposed to travel through when draining. :thinking: Probably the true cure though is a new door seal, as, again, due to that strange design so that the window presses up against the door seal sideways instead of “edge on” to seal things up. :crazy_face:

Thanks AttyDall - Once I am back on my feet, I will take a look at the door seal on my 1991 XJS to see if I can follow what you are saying so that I may be able to stop my leak problem since I also had water on the driver’s side (LHD) floor mats. Apparently this car has had this problem before I acquired it, since I found that there was extensive surface rust on the left back side of the instrument panel, and also the metal parts behind the driver’s knee panel, and yet there was no sign of such surface rust behind panels on the passenger side - Tex Terry II 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe - 2/4/2020 2003hrs EST USA.

Hmmmm … did you check the WW plenum drains (and hoses) on either side? Sounds like the water is possibly coming from an overflowed/backed-up plenum. Otherwise, I don’t see how water can be reaching the backside of the instrument panel from bad sealing of the door seal … :confused:

Yes, on my 1991 Coupe, I did check the windshield washer plenum and found that there were no signs of water stains depicting backed-up water pooling in that area - I verified that the large drain tubes were clear also. I did verify that the roof drain, along the A pillar was also clear. I did all this checking before I became temporarily disabled from a knee surgery, so I intend to continue the search once I am mobile again. The car is inside my garage, so at least I am not getting more water in at this time. According to my manual, the water, from the roof, should drain down the A post drain, then (also as Kirby stated) vertically down the front side of the bulkhead frame support (which has the door hinge mounts), then horizontally towards the rear of the vehicle, under the door sill section. Along this horizontal run, there are drain holes, on the bottom plane, to allow drainage out to the ground, There is also a horizontal drain, starting in the area of the outside rear corner edge of the bonnet, just under the top edge of the front fender, that drains towards the area just before the headlamp bucket. The service manual states that the fender needs to be removed to gain access to the front side of the bulkhead drain, and the fender top drain, so that the area can be cleaned and resealed so that water will not enter the cabin area, possibly from rust damage at the vertical joint of the door jamb and bulkhead frame. The manual also states that the drain holes, under the door sill section, if blocked, would allow water backup in to the cabin floor area. The area around the windscreen seal is also considered a possible suspect for water entering the cabin area, as well as door edge sealing. I have not pulled the fender yet, or verified that the drain holes under the door sill are open. Hopefully I will be able to locate, and repair the leaky area, and post here - Tex Terry II 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe 2/4/2020 2154hrs EST

Wow, I didn’t know about the door sill drains. I wonder if that also applies to the face-lifts, like my Superblue? I thought it odd that I never have had the drainage problem on the passenger side, and come to think of it it appears the PO must have removed that sill plate for some reason in the past, as it sits kinda perched up now on top of the frame, not in proper position. I have to wonder now if this was done to clear drains on that side? :thinking: If so, maybe the PO thought it such a possible disaster to try to do same with the sill plate on the driver’s side that he passed it up. :confused: Frankly, being that the sill plate design is a bit different on the XJS vs. the other Jags I have owned (XJ40s and X-300) that I am a bit reluctant to mess with it myself, not knowing for sure how to safely remove it and, more importantly, properly reinstall it. :grimacing:

I am of the opinion that the first step, for the drains below the door sill area, is to verify that the drain holes (accessed from laying on the floor and looking up at them - if the car is not on a lift) are open, simply by using a stiff wire to check that the holes (five from front to back) are not blocked - Tex Terry II 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe 2/4/2020 2322hrs EST USA

Ah, I was wondering if it was possible to check if they are clear from underneath. Thanks for sharing that! :smile:

Not sure if this applies to the XJ-S (XJS) but my S11 saloon was leaking water into the drivers footwell and I think (its been dry here lately) that I found the source to be from the heater plenum. On the S11 the plenum shape allows water to sit below the duckbill outlet and this had rusted out. I only discovered this because the Warrent of Fitness inspector pointed out a rust hole developing just inboard of the brake booster.

Hello Robin - would you be able to take another picture, or two, just from a little further away, to help me understand the location you are referring to - this first picture is a good one, but I don’t know where to start to find this location - I understand we have different vehicles, but I still want to check to see if I may also have this location problem - thanks - Tex Terry II 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe, 2/5/2020 1543hrs EST USA.

Its the area in the centre of the shot between the bracket for the brake booster and brake reservoir Sorry its a bit overcast today.