Bulkhead Wiring Loom Modification

The main wiring loom enters the engine bay through a hole in the nearside bulkhead panel. On my car there was no grommet and water was prevented from entering into the passengers side footwell by black sealant.

Bulkhead Wiring Hole

The poor state of the carpets indicated that this sealant was not performing as well as it should so thinking back to a number of techniques picked up from my RAF days I looked into the possibility one or two bulkhead connectors to pass through the loom wiring.

On investigation there are around 30 separate cables to connect some carry signals (low current and voltage) some carry significant amperage. The aircraft industry uses a number of connector manufacturers but the one I remember well was Amphenol and on checking, these are available, but for a significant cost. Ebay has several cheaper alternatives so I ordered a couple to see if they would hold up well. These are the two types.

Bulkhead Connectors 1Bulkhead Connectors 2

Both are waterproof and both have a rubber seal, the left one has a 25A rating and the one on the right is 15A.

Clearly, cutting the main loom and soldering to the male bulkhead connector and to the female is a risky proposition but if you take very careful notes, lable each individual cable and draw up the wiring in a diagram then the risk is significantly reduced.

This is the diagram I eventually came up with.

Bulkhead Interconnects

I decided on making a plate to fit to the bulkhead and make the holes for the connectors. eBay sell Aluminium plate so I picked a piece about 12" square and cut a piece off to the right size.

These are the initial pictures from the manufacture.

Bulkhead Connector Plate 1

I had a little 5mm Rubber matting left over from the chassis pads so I cut out a section to act as a seal.

Bulkhead Connector PLate 2

The original hole was used as part of the cut out and I chopped out the rest witha Multi-Tool saw.

This is it fitted.

Bulkhead Connector PLate 3

More to follw....