returning from work the other night at 04.00.
loud screaching noise-----------------checked all the gauges and instruments, volt meter showing 14 volts,
(belts on) . resister modded temp gauge fine, extra temp gauge fine, heater circuit gauge slightly up a few degrees, and coolant pressure slightly up 
.the screeching wasnt the standard screech assosiated with slack belts when applying the throttle, it was loud when off the throttle
, thinking water pump bearing, or alternator seizing, low coolant and high coolant alarm ok.drove the 10 miles home and will check in the morning.
in the morning found the 2 alternator belts slack
. only checked 2 weeks ago so a bit of a puzzle what has happened.now to the crux of this. the bottom alternator mount was present but the top one had fallen apart, the long tensioning bolt had somehow unscrewed itself and dropped into the lower soundproof tray, the pinch nut and bolt that passes through the slider was still present but slightly loose so the tension on the belts was lost.
when this was removed and examined it was found that this nut is a special nut, it is a lock nut, when this nut is repeatedly removed and tightened it damages the thread on the bolt that goes through the slider effectivly stripping the threads off the bolt. the nut is described as an aircraft type lock nut i think, so when a new alternator is fitted, or belts adjusted, this part must be checked carefully for damage or like mine it wont nip up correctly and may cost you your cylinder head when you loose waterpump effect.
either replace the bolt that goes through the slider or cheat like i did and cut off the damaged thread and weld on a new threaded piece to ensure it nips up very tight.
aint bongo ownership good
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