???? Where exactly is this screw please? I have looked but cannot see anything obvious.
A few months ago I need to get to the horns as one was quite 'piddly' & the other non-existent.
Removed the top of the grille but didn't go further. It was just enough to squirt some CRC into the trumpet sections & give them a good seeing to with a piece of fourby while the horn button was kept pressed. Soon freed them off & they have been fine since, & I often give them a blast of the horn button to keep the vibratory bits free.
South Aussie driver being good & courteous,

meant that I never had to use them much & so they seized. Mind you, the odd high pressure clean may not have helped.
I know this doesn't help with your fans, but I hope you can get something sorted soon.
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