Before you sell your Walloth rad better check to see what it costs to recore these radiators! In WI I don’t think the extra sensor to trigger the electric fan is needed and I don’t have that here in CA.
The estimate was $300 to $400 for a refurb/recore. The idea is that with the sale of the new radiator, I might net out close to zero (I paid quite a bit for the W&N one).
i beg your pardon, i thought the sender should go at the top, right side top, am i wrong ?
thanks
Hello Jesus!
The options-
e9 starts with a second wire to the temp sender for the gauge in the thermostat housing to a small module on the passenger inner fender that operates the auxiliary fan.
e12, e24 and e9 late and e3 late Models get a Sender at the bottom right of the radiator to operate a relay for the auxiliary fan
17111121295
www.wallothnesch.com
an option for a radiator with no opening for a sender is a later “A” Thermostat housing with a 91* sender
The options-
e9 starts with a second wire to the temp sender for the gauge in the thermostat housing to a small module on the passenger inner fender that operates the auxiliary fan.
e12, e24 and e9 late and e3 late Models get a Sender at the bottom right of the radiator to operate a relay for the auxiliary fan
17111121295
Radiator with connector for temperature switch for all models with manual gearbox also for cars without air condition with approx. 25 higher cooling rate compared to the standard radiator you need 1 for 1 car
Radiator with connector for temperature switch for all models with manual gearbox also for cars without air condition with approx. 25 higher cooling rate compared to the standard radiator you need 1 for 1 car
an option for a radiator with no opening for a sender is a later “A” Thermostat housing with a 91* sender
This is very interesting. My original radiator (or the one that was in the car) does not have the lower right sensor port. But I also do not seem to have the second wire for the aux fan. The new W&N radiator I have is the one Don links to above. The mystery of what to do continues.
"IF" I were to drop, say, a later model injected engine in the car (just thinking out loud), would I want/need this lower sender port on the rad?
"IF" I were to drop, say, a later model injected engine in the car (just thinking out loud), would I want/need this lower sender port on the rad?
cars that came after the early e9 came with a temp sender or two! to turn on the auxiliary fan in case the engine got hot.
many cars got resisters and relays allowing two stage hi/lo fan for engine cooling. Smart people used the 82* sender to keep the temps just right.
many cars got resisters and relays allowing two stage hi/lo fan for engine cooling. Smart people used the 82* sender to keep the temps just right.
That sensor was introduced on MY 74 coupes and later models.
Stephen - reading this, it sounds like you are unsure what to do. Remember the aux fan goes on then you switch on your a/c, so the secondary temp switch setup only turns on the aux fan when the a/c is not running and the engine gets hot.
I tend to agree with Chris that this is overkill in WI. Folks in CA find themselves in stop and go traffic with the windows and sunroof open far more often than do folks in WI.
Nonetheless, if you want to go forward, you can do this install with the sensor in the port at the bottom of your new radiator by adding a second wire as an alternative method to excite the relay that powers the fan. To do this, install the sensor at the bottom of the radiator, run power from the battery to the sensor, and then run a wire from the sensor to the same terminal on the relay as the wiring from the temp switch (black wire to terminal 86). When the sensor hits its design temperature, it will close, complete the circuit, excite the relay and send power to the fan. If you go this route, you should add a blocking diode on the wire from the temp switch to the relay at terminal 86 to ensure the sensor switch circuit does not flow power back to the temp switch.
You can also wire up something similar to this using a sensor in the tstat housing, but (and I hate to contradict Don on this) I would not use the coolant temp sensor that sends the signal to the temperature gauge in the dash. That thing is not a switch, but is instead a thermistor. I know there are M30 tstat housings that will allow a sensor switch to be installed; if you kept your original radiator and went this route you may need to consider whether 82C is the best alternative, or whether some other trigger point is better.
I tend to agree with Chris that this is overkill in WI. Folks in CA find themselves in stop and go traffic with the windows and sunroof open far more often than do folks in WI.
Nonetheless, if you want to go forward, you can do this install with the sensor in the port at the bottom of your new radiator by adding a second wire as an alternative method to excite the relay that powers the fan. To do this, install the sensor at the bottom of the radiator, run power from the battery to the sensor, and then run a wire from the sensor to the same terminal on the relay as the wiring from the temp switch (black wire to terminal 86). When the sensor hits its design temperature, it will close, complete the circuit, excite the relay and send power to the fan. If you go this route, you should add a blocking diode on the wire from the temp switch to the relay at terminal 86 to ensure the sensor switch circuit does not flow power back to the temp switch.
You can also wire up something similar to this using a sensor in the tstat housing, but (and I hate to contradict Don on this) I would not use the coolant temp sensor that sends the signal to the temperature gauge in the dash. That thing is not a switch, but is instead a thermistor. I know there are M30 tstat housings that will allow a sensor switch to be installed; if you kept your original radiator and went this route you may need to consider whether 82C is the best alternative, or whether some other trigger point is better.
Hello Jesus!
The options-
e9 starts with a second wire to the temp sender for the gauge in the thermostat housing to a small module on the passenger inner fender that operates the auxiliary fan.
e12, e24 and e9 late and e3 late Models get a Sender at the bottom right of the radiator to operate a relay for the auxiliary fan
17111121295
Radiator with connector for temperature switch for all models with manual gearbox also for cars without air condition with approx. 25 higher cooling rate compared to the standard radiator you need 1 for 1 car
Radiator with connector for temperature switch for all models with manual gearbox also for cars without air condition with approx. 25 higher cooling rate compared to the standard radiator you need 1 for 1 car
an option for a radiator with no opening for a sender is a later “A” Thermostat housing with a 91* sender
dear Don, this is a nice approach, so two locations, radiator 80ºC or tstat housing 91ºC
i am still wondering why the sender in the radiator case is located at the bottom, for example an e28 car has two senders 80degC for first speed of fan and 91degC for second speed, but those senders are in top right at radiator
was e9 bottom right ?
what do you think ?
We use a 91* C sender / switch if we go to tstat housing - perfect for keeping engine from going over 195* F
Part number 61311364272
12 bucks
We always take power from a switched source and add a fuse.
The temp gauge sender used in 1974 to actuate the fan was a BMW idea.
Part number 61311364272
12 bucks
We always take power from a switched source and add a fuse.
The temp gauge sender used in 1974 to actuate the fan was a BMW idea.
In the beginning the e28 used 2 senders as you say.
91*
99*
It was a bad idea....
Everyone threw away the 99* one and bought a 82* one. Now the system worked right.
82*
91*
91*
99*
It was a bad idea....
Everyone threw away the 99* one and bought a 82* one. Now the system worked right.
82*
91*
Yeah, Don makes a good point here. Power to the relay through the flying fuse behind the right front headlight for the aux fan is unswitched, so if you use unswitched power for the temp sensor as I suggested for the second wire to excite the relay, the fan will continue to run after you shut off the car so long as the coolant temp is high. And, of course, there will be no airflow to cool down the coolant, so it will run and run and run. My Saab 900 used to do this, and I used to think it was cool.
Don has guided me to use the rad temp sensor and a diode to run direct to the relay but I can’t find my diagram.
Old mans thoughts.....
in 1980? BMW came out with a 4 min timer actuated by the water temp sensor positioned between cylinders 5 & 6 on the block.
It wasn’t meant to cool the water- it was a turbo cooler fan controller. the fan was hidden in the front bumper.
in 1980? BMW came out with a 4 min timer actuated by the water temp sensor positioned between cylinders 5 & 6 on the block.
It wasn’t meant to cool the water- it was a turbo cooler fan controller. the fan was hidden in the front bumper.
I will post a diagram if you want Chris
MTYPE
Well-Known Member
Found your chicken scratching! Triangle in drawing is the diode to prevent current from going to the compressor.
Ah yes, that is a good upgrade. Is there a specific model/size that has become "the one".
My car has the original elec fan still - not sure if it works. But I remember when I worked at the dealership back in the late 80's. We'd take the original fans out and replace them. I used to take the original fans home and use them on non-automotive projects.