| Author | Message | ||
     Robert Howlett Frequent User Username: bobhowlett Post Number: 92 Registered: 9-2010 |
Hi folks I was given a transmission cooler off a forklift by my brother. Its the right size to fit between the grill and aircon.25mm thick. I've been thinking about removing the water cooler one bolted to the gearbox and taking away that extra heat source, and the pipes that run along the left hand side of the motor by plugging them off .. Has anyone done this? and is worth the effort ? any info would be great. She currently sits on a hot day at about 90c to 110c on a hot day or pushed hard cheers rob | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2816 Registered: 4-2003 |
I would suggest caution with that modification. The heat exchanger already fitted is an excellent one as it is temperature controlled. Furthermore, the one fitted to an early Silver Shadow is ideal as it operates at engine temperature, whilst on later cars it runs at radiator temperature by virtue of those late exchangers being located in the lower radiator tank. The later systems are fine but not as optimal as the early ones. Under most conditions, the engine in your vehicle is warming the transmission fluid to around 90 degrees and keeping it there. It is, of course, controlled by the engine coolant thermostat. Without a cooler, or with an air-to-fluid cooler, the transmission will normally run cooler than optimal and never warm to the desired temperature. That is why additional transmission coolers are almost always just that: an additional cooler in-line with the existing system so that the transmission retains a sound level of temperature control. Of note is the engine oil cooler introduced first on Turbocharged SZs. Those systems have their own thermostats to ensure that the engine oil does not operate too cool. A similar thermostat would be possible with an independent transmission cooler, but it would be a lot of work for no benefit. It should be noted that the amount of energy involved in the equation is almost negligible in terms of the engine cooling system, and is of the same order as that of the cabin heating system. If the engine overheats, it is not because of the transmission cooler. Incidentally, Crewe issued a service bulletin to fit an in-line additional transmission fluid cooler to the very early Continental Rs as their transmission controllers were switching the transmission to Hot Mode, locking the torque converter clutch, on long steep hills. At first the cooler was placed before the normal main cooler and had no effect as the main cooler was reheating the cooled fluid, so they repositioned it after the main cooler. That cured the Hot Mode issue, but for the wrong reason. Only then did they realise that heat was not the issue but that the thermistor inside the transmission was to blame. The thermistor telling the ECU of the situation was inherently faulty and poorly located inside the valve body. When the motor works hard, the radiator may reach 90C, but the thermistor was falsely telling the ECU that it was 145C. The additional cooler after the radiator then dropped the temperature to around 75C avoiding the supposed over-reading. GM had already recognised this by 1992 and changed the type of thermistor and relocated it into the wiring harness inside the transmission, but Crewe and Jaguar only made the change for the 1994 Model Year. The recommendation for the additional cooler was then quietly dropped. RT. | ||
| Robert Howlett Frequent User Username: bobhowlett Post Number: 95 Registered: 9-2010 |
thank you Richard point taken mmmm certainly something to think about many thanks cheers rob |
