Td5 D2 bodywork - Heater Blower Hole (4)

Fired up the Borroscope and got some photos of the five  Heater Blower intake mounting bolts. 

Orientation was difficult, so I made a little sketch/plan of the area to work..

The viewpoint for the above sketch is from the engine compartment looking rearwards. I am now getting familiar with the shape of the blower intake.

Bolts 1,2 and 3 are hidden from view by the plastic plenum cover. Bolts 4 and 5 are themselves only partially visible.

So then, going clockwise from no1..

looking clean and secure with no rust.

Just above no1 bolt is this 'clip'. It is actually a locating lug from the plenum cover that locates around the bottom edge of the windscreen.. at least that is in the right place.

Attempted to show the proximity of the clip to No1 bolt.. The intake 'wall' is visible at the very bottom of the image..

lf any any rainwater was flowing under the windscreen seal in this area it would emerge here by the clip and flow/fall/drip past the bolt area and over the 'wall' of the intake into the blower inlet.  That seems a crazy thing to suggest, but who knows?  My money is now on a capillary action around the intake gasket joint and bolts. (that could explain bolt No4 's condition)..

Bolt No2 looking undisturbed and secure as does the intake gasket and inlet below the bolt. The three marks to the right are from the Borroscope rubbing along and cleaning the muck away..

Two more views of No2 showing the intake wall at this point. It all appears to be dry and secure..

Bolt No3 looking up..

Bolt No3 looking down... could that be an entry point for rainwater right in the corner? 

Bolt No 3 again. Showing bits of rust and on the intake wall, those white deposits could well be water marks...

Bolt No 4.. easily the most corroded and water stained.

Two views of bolt No 5..  no concerns here.

Having studied the images and looked through the Borroscope I can conclude that the intake mounting on the bulkhead is secure and dry with no gaping holes to let the water in. That is not to say that water is not getting in there though and attention is drawn to the area between bolt 3 and 4...

Here is a photo looking up at the lower corner of the intake between bolt 3 and 4. Bolt 3 is visible in the distance .

All the water damage visible could well be historical. Don't forget that the lower windscreen seal was only 'sealed' last year with mastic itself..

In conclusion I will apply mastic sealer all along the joint from bolt 3 to 4. At least this area can be accessed easily by hand.

But that still leaves the possibility of water entering the intake directly from above so the need for some kind of a cover is still valid.