MG Motoring 2018 July 2018-opt | Page 10

MG Car Club of South Australia MGC NEWS MGC conversations with Richard Mixture, July 2018 There wasn’t a part number on the old clutch, so after some searching, a Tru- flow fan clutch TFC137 was found that suits GMH and Nissan. The height was 60.5mm. The fan seat on the clutch allowed the fan to sit closer to the en- gine giving 23mm gap between the fan and radiator core but only 12.5mm be- tween the clutch body and core which is not a lot. In other words the clutch body protrudes through the middle of the fan and is closer to the radiator core than the fan itself. You have to make sure your engine mounts are in good condi- tion! MGC fan clutches H ello again, it’s Richard here. Now, for an engine to run effectively it needs to operate at the correct tempera- ture. When the engine coolant is cold its flow through the radiator is restricted by a thermostat and when it gets too hot, the thermostat must be open and a fan helps air flow through the radiator to cool it. All of these bits must be working correctly if you’re going to have fun in your MG. Now, I’m sure all you MGCers reading this will think I’m trying to tell you how to inhale eggs, but if the old six pot lump of cast iron gets hot it won’t like it. Well, that’s what happened to that nice young Register Co-ordinator, his engine got hot and spewed coolant everywhere! Taking a look at the original factory fan, the distance taken by the original spacer and metal fan leaves a similar space between the fan and the radiator core. The original fan spacer is 26mm thick and the fan from the mounting surface to the fan blade edges is also 26mm. Add- ing these two together and subtracting it from the 73mm distance between the water pump flange and core leaves a 21mm gap, 2mm less than the modifica- tion above. The suspected culprit was the fan clutch. Now those readers that are ex- pert on matters dealing with MGCs will know that MGCs don’t have a viscous clutch that operates the fan. So why is there one on our nice MGC Co- ordintor’s ‘C’? Well he answered that question by saying the modification “sounded like a good idea at the time” (2003) and anyway Bruce did it. You know, that nice old Queenslander, Bruce. With the engine idling, the fan was checked by carefully inserting a rolled up magazine into the blades and it was easily stopped indicating there was no oil in the fan clutch. The other modification that is needed is to drill two extra holes in the fan clutch mounting flange. Fan clutches are nor- mally mounted to the water pump flange with four bolts. The MGC water pump pulley and fan are mounted using only three bolts. The original spacer can be use as a template to drill these extra two holes. One might wonder if the saving of one bolt was a cost saving measure imposed on Abingdon by BMC account- ants? Now, many of you will know that the ‘C’s six cylinder engine is a long one and there’s not a lot of room between the water pump pulley and the radiator core. The fan and clutch has to fit in a space of only 73mm. The length of these three bolts is critical in order to fit behind the clutch mounting flange and its body and still have 8