Black tarry finish in boot

[cormorant]

Anyone know what this stuff actually is (1967 rose taupe saloon) and what to use to patch it in if necessary? I am going to clear my boot out soon and have a session in there - tidying up, rustproofing and generally preserving the whole area in preparation for winter.

[Jefftav]

Is it an old rust proof treatment ( waxoyl or similar) it might even be tar stranger things have happened.

Tread carefully as when I did this 2yrs back it turned out the inner wings were in pretty bad condition. This is OK if you are prepared and ready to do the work.

[PSL184]

Yes I think it is a bitumen based sealer and as Jeff says it is quite common to find out that it is the only thing holding the seams together, particularly around the rear wing to inner wing seam....