Waterlogged battery compartment.

ben g · Post by **ben g** » Sun Jan 13, 2019 7:51 pm

I went away for Christmas and new year, so my Z4 didn't move for a couple of weeks. Upon returning, I noticed quite a lot of water in the battery compartment under the boot floor.

I have managed to dry it out completely, but I don't particularly want this to happen again.

Any ideas what could cause this? And any known fixes?

Unsure how water has got in there, but I do know sometimes I get small pools of water on the 'pockets' in the left and right side of the boot, which I can't seem to trace to any source.

Ewazix · Post by **Ewazix** » Sun Jan 13, 2019 8:38 pm

Worth a read re the boot air vents viewtopic.php?t=84102

or rear light seals and centre brake light seal have been mentioned before

ben g · Post by **ben g** » Sun Jan 13, 2019 9:00 pm

I've replaced all those

still getting water ingress from somewhere. Unsure how it's managed to get into the battery area though.

Usually the wet patches are in these parts on both sides:

: sketch-1547409553834.png (1.18 MiB) Viewed 1204 times

I can't see how water could get from these areas, down to the battery area, so there must be another way for water to get in

-Tom- · Post by **-Tom-** » Sun Jan 13, 2019 9:01 pm

This might sound random , but did you have a half cover fitted over the roof whilst you left it ?

mr wilks · Post by **mr wilks** » Sun Jan 13, 2019 9:07 pm

Did it start to happen or worsen after the change of roof ?

ben g · Post by **ben g** » Sun Jan 13, 2019 9:41 pm

mr wilks wrote: ↑Sun Jan 13, 2019 9:07 pm Did it start to happen or worsen after the change of roof ?

I always had the patches of water in the right (drivers side) pocket of the boot, regardless of whether the hardtop was fitted or not. The passenger side area seems to be a new development. I'm unsure when the battery compartment began filling with water as I haven't checked that area for a good while

-Tom- wrote: ↑Sun Jan 13, 2019 9:01 pm This might sound random , but did you have a half cover fitted over the roof whilst you left it ?

No cover whatsoever. I did have a hardtop fitted up until a month or so ago, but as above, having that fitted didn't stop the water ingress into the boot.

mr wilks · Post by **mr wilks** » Sun Jan 13, 2019 9:43 pm

No i was meaning when you changed the soft top from original ? Is it possible not all rainwater is getting to the outlets ?
Though having hardtop on & it still happening ? More puzzling

MACK · Post by **MACK** » Sun Jan 13, 2019 10:08 pm

This happened to me when my drivers side roof drain blocked recently. Parking on a slight incline, front pointing uphill, cambered to the drivers side at home and work didn't help either. Drains cleared (my drivers side was completely blocked) parking in the same places but with the front down hill and in the last three weeks its not happened again.

Striven · Post by **Striven** » Sun Jan 13, 2019 10:31 pm

Can someone point out where all these drains are, I would be keen to keep them clear IF I knew where they were. Might be why my passenger footwell gets wet.

ben g · Post by **ben g** » Sun Jan 13, 2019 10:43 pm

MACK wrote: ↑Sun Jan 13, 2019 10:08 pm This happened to me when my drivers side roof drain blocked recently. Parking on a slight incline, front pointing uphill, cambered to the drivers side at home and work didn't help either. Drains cleared (my drivers side was completely blocked) parking in the same places but with the front down hill and in the last three weeks its not happened again.

Cheers MACK, that's food for thought, as my driveway is on a very slight incline. If I leave my handbrake off, the car gradually rolls backwards, so I'll reverse park instead and see if that makes any difference.

I haven't checked my roof drains for a good couple of years, so that's probably my next job

What did you use to clear the drains? Last time I done mine I used a bit of wire and went up from under the sideskirt. Any better ways of doing it?

ph001 · Post by **ph001** » Sun Jan 13, 2019 11:39 pm

You can easily confirm if they are clear by dropping the roof and filling a jug with water. Pour a little down the cavity next to the roof hinge mechanism. If it doesn’t immediately appear on the ground just in front of the back wheel then you have a blockage.

craig3.2 · Post by **craig3.2** » Mon Jan 14, 2019 12:29 am

Striven wrote: ↑Sun Jan 13, 2019 10:31 pm Can someone point out where all these drains are, I would be keen to keep them clear IF I knew where they were. Might be why my passenger footwell gets wet.

Passenger footwell leaking is Normally down to Door Membranes not being replaced when having work on windows/regulators,etc replaced.
You should always renew the door membrane,but some don't,and they end up coming loose,then water gets into the footwell.
Failing that,Door seals,but look at the Door Membranes first

Apologies for the Thread hijack,Op

MACK · Post by **MACK** » Mon Jan 14, 2019 12:31 am

ben g wrote: ↑Sun Jan 13, 2019 10:43 pm
MACK wrote: ↑Sun Jan 13, 2019 10:08 pm This happened to me when my drivers side roof drain blocked recently. Parking on a slight incline, front pointing uphill, cambered to the drivers side at home and work didn't help either. Drains cleared (my drivers side was completely blocked) parking in the same places but with the front down hill and in the last three weeks its not happened again.
Cheers MACK, that's food for thought, as my driveway is on a very slight incline. If I leave my handbrake off, the car gradually rolls backwards, so I'll reverse park instead and see if that makes any difference.

I haven't checked my roof drains for a good couple of years, so that's probably my next job

What did you use to clear the drains? Last time I done mine I used a bit of wire and went up from under the sideskirt. Any better ways of doing it?

I used the airline at a friends garage. If I didn't have access to an airline I guess I'd use the good old wire/coat hanger technique etc.
I think I mentioned it in a thread at the time that my drivers side was block with one of those "helicopter" seeds and other gunk. I only cleaned them out in June as well!
+1 the jug of water near the hinges to check if the drains blocked. If it is it might be worth trying a bit of hot water in the same area, sometimes when mud etc has blocked the drain it softens it enough to "break the seal". Enough to get things flowing again until you can clean them out properly.
I had a lot of water in the area highlighted in your photo and a few drops in the compartment behind the battery, I bet it could be tipping over from into there when the vehicles moving etc.

ben g · Post by **ben g** » Mon Jan 14, 2019 12:33 am

Will give the jug of water a go tomorrow and see what happens. Hopefully that's the source of my problems

cheers

Lance · Post by **Lance** » Mon Jan 14, 2019 1:27 am

Ben I had a water leak exactly how you're describing it and i spent weeks trying to trace it! It drove me mad!

Checked the drains, light clusters were taken out and seals checked, air vents checked but all with no obvious signs of leakage. I finally siliconed around the joins/creases around the boot opening, near where the hinges and struts sit, also the top line of the lights. Never leaked again after that and it's probably been 5 years.

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