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Slipping Fan Belt

A common problem with RMB/RMC/RMDs is a slipping small fan belt which cannot be cured by adjustment.


Adjustmernt of the belt is quite easy by slackening the pinch bolt holding the fan assembly and rotating the assembly using a rod pushed into one of the holes and then rotating the assembly. Unfortunately the amount of adjustment is quite limited and if the pulleys are worne it may be insufficient.


Many of the belts sold today are of a single piece construction with a fixed length unlike the Whittle link belts shown on the Workshop Manual and the Driver’s Handbook which can be shortened if necessary.


There is no real cure for worne pulleys apart from replacing them with unworne ones.  Short term solutions might be to use a slightly wider belt which does not sink so far into the pulleys if you can find one or to revert to the link type belt which can be shortened as needed.  Linked belt is still used on machinery such as lathes and is often found advertised on Ebay in various widths. A one metre length is typically £15. If the pulleys are very worne the belt may still bottom in the groves and slip but in view of the modest outlay needed it may be worth a try.  It should be noted that it has been reported in the past that aluminium pulleys wear faster with link belts than they do with smoother one piece belts.


A longer term but less original solution would be to remove the fan assembly completely and fit an electric fan between the front grill and the radiator as many people have already done to improve cooling at low speeds.  To retain more of an original look the belt only could be removed leaving the fan assembly in place. The fan will then be free to spin in the air flow although it will not itself aid the air flow.