Dear james_a_sousa,
Hope you're well. The factory-installed "black gunk", that secures(d) the cowl's screen can be replaced with butyl rubber, a very sticky and very durable adhesive.
Butyl rubber is used by automotive glass installers, to bed windshields. Because it remains flexible, it does not crack (fail) as a result of repeated extreme temperature variations, which cause a windshield to expand and contract.
On my 940, I removed the failed factory-installed "black gunk" from the spaces between the grille openings. This was not hard to do, as the stuff had dried-out.
I cleaned the metal using MEK. MEK (methyl ethyl ketone) is a very efficient solvent. It is a chemical cousin of acetone, but evaporates more slowly. MEK removes oil/grease and other surface contaminants. NOTE: MEK is very flammable. It is also carcinogenic, mutagenic, and teratogenic: wear gloves!!!!
I filled the spaces between every fourth grille opening with butyl rubber in round cross-section. I positioned the grill, and then pressed it into the butyl rubber. To ensure it stayed "put", I applied more butyl rubber atop the screen, pressing on it to make sure it bonded with that beneath. The screen is fully embedded in butyl rubber, which firmly adheres the screen to cowl.
I did this, because cowl removal - not especially hard - is time consuming. So, I wanted to do this job, such that it would not soon need to be repeated.
Years later, the screen remains where it should be.
Hope this helps.
Yours faithfully,
Spook
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