SL65MONSTA

I hardly drive my 65 these days and as I leave it parked for a few months, some reason the serpentine belt and pulleys give up, Mysteriously! This is the second time its happened to me in 2 years.

So I hardly drive my SL65 and it sits for a few months at a time until I drive it the next time, however what seems to happen every time it sits for awhile as soon as I drive off literally 10-15kms away from home, the serpentine belt gets chewed up, it chews up the tension pulley plastic wheel, and the top pulley wheel that sits in the middle of the motor.

Someone said it was the "harmonic balancer"to be replaced , but they just did a quick visual inspection as it appeared to be bouncy (serpentine belt) but I have pulled this off and inspected it, it appears ok and all rubbers are in tact. I know the water pump definitely needs replacing as I turned all the pulleys to see which one would be faulty and there is major play on the water pump shaft in it, however the issue is this im not sure if the play on the water pump was caused by this situation that happened, or if it was the cause of it all. Very expensive exercise especially when you have to replace 3 pulleys every year and you only drive it literally 15kms away and this happens, parts for this car are not available in Australia and need to be imported from US or UK and it takes weeks on weeks to arrive, sometimes being the wrong parts too!!

Im thinking the serpentine belt needs to be taken off if im going to park the car for months at a time, and also the coolant as it may have corroded the rubbers , I highly doubt coolant is this corrosive to do this damage. or maybe its just the water pumps lifes over (I hope!)

Upon pulling off the water pump today, one of the longer nuts that holds it in had all black rubber burnt into the thread im assuming this is the "rubber sealing on the water pump corrosion"

has anyone else experienced this issue , if so what causes it as it is so painful when you just want to take your beauty out for a drive and you need to call a tow truck, and your car gets to overheat within 2 minutes as the water pump is not working due to the serpentine belt snapping off! oh not to mention how hard the steering gets, impossible to take any decent turn with more then 15 degrees on it, and quiet dangerous actually if at a high speed. Car turns into a boat and ABC fails! , stupid design by Merc to have one belt drive every system of the car!!!!