P38A thermostatic control for fans

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tarphenry

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bury lancs
Hi all, I am intending to add a thermostat attatched to the 2 aircon fans to aid cooling(if needed) after towing up long climbs or sitting in traffic. I want to be able to st the temperature just above normal. With this in mind I have purchased sais thermostat but it las a long 2" 5 mm dia probe. I am looking to see if anyone has found a suitable location (keep it clean) its on a diesel so the radiator pipes are not that long to insert a steel piece into, Any help would be greatfully received thanks Mick
 
I did this with mine, I glued the probe into the rad fins near the inlet pipe in the rad. Then set the temp setting using a hand help laser temp reader pointed at the radiator inlet. Regardless of the thermostat setting figures.👍
 
I then dropped the mod and went for an all aluminium rad and a mahle viscous fan. For me personally it was too much of a shock for the radiator and it was bursting them every two years😵‍💫 the last burst could have blinded me🥴
The viscous has more of a sensitive approach to the heat I find. She pulls cars and goes off-road and copes well.
It also heats up quickly because she is programmed producing heat quicker than my son's standard engine program.
There is a debate about the electric fan compared to the viscous fan and having had the system done both ways, like this, it works very well for me 😎
 
Hi all, I am intending to add a thermostat attatched to the 2 aircon fans to aid cooling(if needed) after towing up long climbs or sitting in traffic. I want to be able to st the temperature just above normal. With this in mind I have purchased sais thermostat but it las a long 2" 5 mm dia probe. I am looking to see if anyone has found a suitable location (keep it clean) its on a diesel so the radiator pipes are not that long to insert a steel piece into, Any help would be greatfully received thanks Mick
I use a stat cable tied to the top hose and covered with pipe insulation. It has the advantage that the temperature can easily be set to whatever level you want. I have a complete mod for using the aircon fans, if you want it PM me with an email address. I have run a P38 with no viscous fan just using the aircon fans for more than a decade with no problems.
 
I then dropped the mod and went for an all aluminium rad and a mahle viscous fan. For me personally it was too much of a shock for the radiator and it was bursting them every two years😵‍💫 the last burst could have blinded me🥴
The viscous has more of a sensitive approach to the heat I find. She pulls cars and goes off-road and copes well.
It also heats up quickly because she is programmed producing heat quicker than my son's standard engine program.
There is a debate about the electric fan compared to the viscous fan and having had the system done both ways, like this, it works very well for me 😎
It's not that the viscous is more sensitive, it's just that it runs all the time to some extent. Off road use is a different situation as the vehicle is often moving at low speed so a cooling fan is needed. Used on the road, most of the time above about 30mph, no fan is needed so the electric fans don't run. For off road use, you could have set the fans to come on earlier and in any case the crap plastic RAD bursting is down to pressure which should be released by the cap on the expansion tank long before the limit of the radiator is reached.
 
I use a stat cable tied to the top hose and covered with pipe insulation. It has the advantage that the temperature can easily be set to whatever level you want. I have a complete mod for using the aircon fans, if you want it PM me with an email address. I have run a P38 with no viscous fan just using the aircon fans for more than a decade with no problems.
 
On the head on newer engines , there is an overheat switch that comes on about 110 degrees n brings on the aircon fans usually a bit 2 late Anyway if that could be changed to one about 100c it would save a lot of fafing about n would cool sooner ,just a thought.;)
 
On the head on newer engines , there is an overheat switch that comes on about 110 degrees n brings on the aircon fans usually a bit 2 late Anyway if that could be changed to one about 100c it would save a lot of fafing about n would cool sooner ,just a thought.;)
I've thought about that also, it would be nice to know the thread size and find a sensor??!
 
On the head on newer engines , there is an overheat switch that comes on about 110 degrees n brings on the aircon fans usually a bit 2 late Anyway if that could be changed to one about 100c it would save a lot of fafing about n would cool sooner ,just a thought.;)
Except 100C is also too late. My mod is aimed at replacing the viscous fan not providing a back up which the third sensor continues to provide.
 
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