I recently replaced all the cooling pipes on my '86 635CSi but I've noticed that the hose running from the bottom of the radiator to the thermostat is already damaged again.
The hose runs *so close* to the waterpump/radiator fan assembly that it appears to be occasionally touching the pulley that drives the fan and vbelt system. This is slowly cutting a slit in the pipe.
My local garage has told me that they've seen this before when the waterpump bearing is going and the freeplay in it allows the belt pulley too much movement. In my case they reckon this isn't happening and they're flummoxed.
Anyone else ever seen this?
It's a proper OEM pipe so it ought to be the right shape and when the car is stationary there's about 4mm of space between the pully and the pipe.
Heeelp!