Water in the sill..how and why?

germanmetal · Jun 7, 2009

Hi,
Was looking in the sill inspection vents and noted traces of water after a very heavy downpour.Where would the water be getting in from.
As far as i know the sunroof drains extend to the front and back and don.t enter the sill area so not sure.

Many thanks,

germanmetal · Jun 7, 2009

Hi scotty,the cavity has been fulllllly sealed with bilt hamber cavity wax with a thinner cavity creeper to fully seal the sills.All of the drain holes were filled with tie wraps that were removed once dry to allow draining.

The car has stood for 3 days and has not been driven in the downpour.

I can't figure it out!

Neil Haughey · Jun 7, 2009

Possibly condensation?

germanmetal · Jun 7, 2009

It was just after the humungous down pour last night.I checked the sills around 3 days previous;for no particular reason.They seemed ok.

Alpine · Jun 7, 2009

I don't think it is wise to seal off the drain holes; they are needed to let the cavity breathe to dry out any condensation, and to let out any excess water

germanmetal · Jun 8, 2009

Hi phil.the cable ties were only there to prevent the cavity wax sealing the drain holes.They were removed once the wax had set.

Many thanks,

zcacogp · Jun 8, 2009

Neil,

'Tis a good question. I have wondered it hypothetically - the fact that there are drain holes in the cills means that something must have to drain out of them ... therefore it's reasonable to assume that there are circumstances in which water will get into them.

I have seen a (series 1) MX5 which was making a 'sloshing' noise whenever you put the brakes on, or accelerated, or went 'round a corner. Owned my a neighbour who is also a friend, and he bought it to me asking what was up with it. I drove it around, pinpointed the problem as being cill-related, and poked around at the drain holes on that. Well over two litres of water gushed out of one side ... but the problem there was that it was a very ropey example, and I think there were problems with the hood and drainage from that, coupled with a very cheap repair (the respray of which had blocked the cill drain holes), had caused the problem.

In terms of what you have done (waxing, then unblocking the drains), that sounds very healthy, but I can't answer your question as to how the water gets there on a 944!

Oli.

James_G · Jun 8, 2009

Yep, petrol filler drain grommet on mine had shrunk, leading to water getting inside, leading to this:

Which when prodded, gave this

And also this, as the leaking water runs down over both sides of the inner wheelarch.

Thankfully, I have now had all of this sorted out, but I wish I had known about it sooner. The grommet cost less than £1 from the OPC and takes just a few minutes to fit, so I'd probably replace it just to be sure.

Hilux · Jun 8, 2009

In terms of what you have done (waxing, then unblocking the drains), that sounds very healthy, but I can't answer your question as to how the water gets there on a 944!

Could be a door seal leak above allows water to trickle down to the vent hole below the lock strike plate? Seal the vent with Dum Dum so its removable. The vent grille is not sealed around the edges.

Its interesting, is it not, that the rear sills rot at this point ie: just below the vent hole onto the inner cill side where it cant easily escape? [

]

mike220 · Jun 8, 2009

ORIGINAL: sc0tty

Of course, the simplest alternative is to not let it get wet in the first place, ie put the car in the garage or get a cover for it.

It's a car, not a cardboard model ! I bought mine to use, apparently Porsche also made them to go outside, hence the windscreen wipers [

]

Mike

Frenchy · Jun 8, 2009

The fuel filler drain has a metal insert with a 90 degree bend in it, this clogs up with crud remove it and clean it !

mike220 · Jun 8, 2009

Chill out Scotty, it was just a little humour. I was simply stating I will use it no matter the weather - mine has the same issues as they ALL will have/have had to some degree. I'm currently restoring this area on my own ('88 Turbo) so know full well the extent of the issue. Unless a car has had this area properly cut out and restored, I'd suggest it has issues to some extent, whether they have presented themselves externally yet or not. Mine will be in just fine condition once done Ta [

], and will get used afterwards the same as before. I bought a car, not an inclement weather ornament. Like you say we have plenty of rain, so waiting for a dry day as regularly as I like to drive is somewhat of a challenge.

It is garaged (at night but it's more for security I guess), but that doesn't mean there's a barometer lock on the door [

]

Mike

Hilux · Jun 9, 2009

Yes but the B post vents are louvred downwards, so surely water can't be getting in that way?

As I said in my post "The vent grille is not sealed around the edges"

Its a push fit only so water trickling down will run in behind it.

pauljmcnulty · Jun 9, 2009

The sills are designed to be open to airflow, hence the black vents. If air can get in then moisture can too, at least via condensation and as water through plenty of routes, including those mentioned.

The idea is, as with the doors, that excess water drains out of the hole so keep them clear. Any moisture left is dried by driving the car to sir the sections, so don't put the car in a warm garage wet. If all else fails, the protection on the metal will prevent corrosion so regularly re-treat the insides of the sections, bearing in mind keeping the holes clear. Easy. [

] If only all the cars had this done every year from new.....[&o]

The more tricky areas are the bottoms of the wings and the wheel arches where physical damage from stones, and trapped dirt and salt, will create issues, so keep these clean and protected.

mike220 · Jun 9, 2009

ORIGINAL: pauljmcnulty

If only all the cars had this done every year from new.....[&o]

The more tricky areas are the bottoms of the wings and the wheel arches where physical damage from stones, and trapped dirt and salt, will create issues, so keep these clean and protected.

That's just it Paul, it's about correct maintenance above everything else. All we're finding now is the aftermath of previous owners either thinking they're a little too solid a car for their own good, or just neglecting to perform this part of the service routine. After all, no one would think of running a car for 20+ years without changing the oil would they ?

To be fair, they're still a much more solid proposition than most 80's modern classics, of which are gonna be a MUCH more invloved job to restore/repair properly. I'm saving mine, just cos it's worth that - saving ! Look at an RS turbo (S1 or 2) for just how bad things can get when cars aren't galvanised etc. most need major surgery by now if they haven't already had it several times over [8|]

I'll do a thread on mine soon if anyone wants to see ? It's currently got lots missing, and is in the process of having the new metalwork welded in in the next week or so.

knightma · Jun 9, 2009

Neil,

I have exactly the same with my S2. The sills get water in them when the car gets rained on, without even being driven. I found this out because the water then leaked into the car under the carpets under the front seats. This problem was solved by unblocking the sill drain holes which I had blocked up with waxoil. During my investigations I found that the water was getting into the sill from the scuttle area in front of the windscreen. If you poor water on the windscreen and let it drain forward into the scuttle it will drain out of the hole at the side and most will end up on the ground. However if it's like mine some will find it's way into the sill. How it gets there I haven't found out but at least it's not now getting in the car since I unblocked the sill drain holes.

Does anyone know how water gets from the scuttle to the sills and if it can be stopped?

Regards

Pastry · Jun 9, 2009

the 944 certainly seems to be a leaky bastard in a number of inventive ways.

mine had a puddle of water in the battery tray, turned out the n/s boot lock had corroded and water was draining through the rusty metal and down the outside of the drain tube, being blocked from egress by a rubber grommet and hence draining instead to the battery tray and when that filled up the space behind the rear wheelarch. stripped it and wire-brushed the offending piece, then cleaned and regreased the lock before refitting. it and seems sorted now.

unrelated to your problem just thought i'd add it to the list of watery woes. i'll be doing the syringe test on the fuel filler drain tomorrow

by the way the rubber seal for the bootlock is HUGE when you pull it out and takes a lot of effort to put back, if id have known i'd have bought a new one to replace it.

if anyone knows a 'trick' for doing it i'd be grateful.

pauljmcnulty · Jun 9, 2009

the 944 certainly seems to be a leaky bastard in a number of inventive ways.

To be fair, an old mechanic friend of mine once welded the sills on a car that had been factory fitted with water-absorbant and inflammable foam. Think it was an Alfa. We're fairly fortunate in some ways! [8|]

James_G · Jun 10, 2009

ORIGINAL: Pastry

by the way the rubber seal for the bootlock is HUGE when you pull it out and takes a lot of effort to put back, if id have known i'd have bought a new one to replace it.

if anyone knows a 'trick' for doing it i'd be grateful.

I used some silicon grease that came with a new thermostatic shower valve. I tried the first one without and it split, which was iritating as it was new, but with the grease the second one slipped in no problem at all.