B400 - battery tray - rust prevention
 

After I'd took off the battery with a rubber pad underneath I detected some water and a lot of rust bubbles. So the rust must be removed and the tray needs new paint.

Does anyone has a proofed solution to avoid this situation with water under the battery? May it be sufficient to place the battery on three glueded spotted pads?

Or is it totaly unnormal that water resides on the tray?

Bela,
often water enters the battery box area at the rear of the central bonnet hinge.
On the later production 400's there is a small square catch area for this water just below the rear bonnet hinge bracket and a steel drain tube that is attached on the inside of the firewall , then down to the road . Sometimes this tube becomes blocked and the water overflows into the battery box area .

Early production cars don't have this drain tube .
Pls advise the chassis number of your car and post a photo of the this area of the firewall.

Geoff

Geoff

car is 374.

There is a little reservoir. I have to see if the drain is clogged.

After grinding the battery tray I come to the conclusion it was not well prepared before painting - too much rust under intact paint. I hope I did a better job this time and a little hole had been fixed.

The drain for the hood is not optimal. The gutter is not very high and falls in the wrong direction. The outlet of the gutter is connected with a drain pipe behind the instrument panel using a hose. The difference in height between the gutter and the drainpipe is very small so that the water does not get down easily and stays in the hose. It may be necessary to lower the inlet of the drainpipe by shortening it.