eFan timer time

[Transpoquick]

What? U lost me there. When the fan runs w/ engine off it cools the fluid in the radiator that brings warm coolant into the radiator.
It's that whole "hot air rises" thing.
I know it's complicated.
Your jeep doesn't apply to the laws of physics though.

 

[Transpoquick]

Oh and btw, if you wire the relay coil to the battery instead of the ignition switch, the fan will run untill the setpoint of the adjustable relay.
Using the factory ground for the fan motor will stop the fan after awhile if you turn the key to first position(if you feel it's draining the battery), that's how it works on a 2k anyway.

 

[Transpoquick]

All good though, my jeep ignores the laws of physics to.
For some reason i see about 190 degrees on the temp gauge all the time.
This is odd because more than one poster on this website has said installing a 180 degree thermostat will not make my 186k engine run any cooler.
I think it's​ broke, something is wrong, wtf?

 

[ehall]

With the engine not running it would be pretty much impossible to reduce the coolant in the block with only a fan.

Coolant is pretty efficient at heat transfer and will carry the heat out of the block even with the pump off.

My efan is on a temperature switch in the upper radiator hose and is wired directly to battery power. What typically happens when I park is the coolant in the head gets hot enough for the thermostat to open, and then the heat moves to the colder coolant in the upper hose, and activates the switch. Then after the coolant in the hose cools back down (a minute or so) the fan turns off. Process typically repeats a few times until all the engine coolant is below the thermostat temperature.

FWIW the only time I have had it drain the battery was when the switch got baked and stuck in closed position. Otherwise no problems with direct battery connection.

 

[Transpoquick]

Coolant is pretty efficient at heat transfer and will carry the heat out of the block even with the pump off.

My efan is on a temperature switch in the upper radiator hose and is wired directly to battery power. What typically happens when I park is the coolant in the head gets hot enough for the thermostat to open, and then the heat moves to the colder coolant in the upper hose, and activates the switch. Then after the coolant in the hose cools back down (a minute or so) the fan turns off. Process typically repeats a few times until all the engine coolant is below the thermostat temperature.

FWIW the only time I have had it drain the battery was when the switch got baked and stuck in closed position. Otherwise no problems with direct battery connection.

Yes,yes!!
And actually I think my engine runs closer to the 180 mark but, I have to plumb the sending unit for my autometer gauge in somewhere.
The thermostat housing is all filled up!

 

[trippled]

Coolant is pretty efficient at heat transfer and will carry the heat out of the block even with the pump off.

My efan is on a temperature switch in the upper radiator hose and is wired directly to battery power. What typically happens when I park is the coolant in the head gets hot enough for the thermostat to open, and then the heat moves to the colder coolant in the upper hose, and activates the switch. Then after the coolant in the hose cools back down (a minute or so) the fan turns off. Process typically repeats a few times until all the engine coolant is below the thermostat temperature.

FWIW the only time I have had it drain the battery was when the switch got baked and stuck in closed position. Otherwise no problems with direct battery connection.

Interesting. I understand how heat transfer works and rising/falling temps, I just figured it would not have enough effect.

 

[Transpoquick]

It does, mine works exactly as ehall described.
No hard feeling's, I can b a transpodick at times.
Bwah:yap:

 

[CarbonXJ]

I still don't understand why anyone would want to control a fan that cools their engine w/ time instead of temperature.
It's odd, what if the engine temp doesn't come down enough in the time that's set?, I must be missing something.
Sorry op I'm "hijacking" your thread.

I'm not cooling the "engine" - I'm cooling "under the hood". It's the under hood temps thanks to the mini cats under the intake that create the vapor lock during short stops. Moving the hot air out and away from the fuel rail is what this is about. I couldn't care less what temp the engine is at.

Usually vapor lock occurs with short stops, around 10 minute average. Running the fan for 3 of those minutes should pull enough air through, coupled with the convection of fluid you just discussed, to cool the underhood area enough to prevent the fuel from vaporizing in the injectors.

 

[ehall]

hood vents will do more for underhood temperature than a timed fan

 

[CarbonXJ]

I already have hood vents and the DEI fuel rail wrap/tray. The timed fan should keep air flowing through the compartment out the vents long enough to keep vapor lock from occurring.

Sent from my LG G4 using Tapatalk

 

[lazyxj]

hood vents will do more for underhood temperature than a timed fan

They didn't solve the hot soak problem in my 2001 XJ.
https://www.flickr.com/photos/lwade/sets/72157632632002979/

 

[Transpoquick]

I'm not cooling the "engine" - I'm cooling "under the hood". It's the under hood temps thanks to the mini cats under the intake that create the vapor lock during short stops. Moving the hot air out and away from the fuel rail is what this is about. I couldn't care less what temp the engine is at.

Usually vapor lock occurs with short stops, around 10 minute average. Running the fan for 3 of those minutes should pull enough air through, coupled with the convection of fluid you just discussed, to cool the underhood area enough to prevent the fuel from vaporizing in the injectors.

Wait a second, what engine is in your jeep?.
And now that you mention the mini cats(which is why I would like to know what engine you have), why don't you just wrap them with some dei header wrap or something?

The whole timed electric fan thing is something that was developed for drag racing. People that don't run an alternator want to put time on it instead of temperature to control the fan in an effort to avoid a dead battery between rounds.

 

[Transpoquick]

I see, my bad. Your in Columbia California bwaahahah!
You should just put California in your screen name, I was thinking your in "Columbia", like south America. Oh that's funny.
So you got California/NY emissions, sucks for you!!
Just wrap the friggin things, that stuff works great!
Good luck!

 

[techno1154]

hood vents will do more for underhood temperature than a timed fan

Actually, I do not have hood vents so I cannot speak about whether or not they work. I guess they do work if installed in the correct place,....many manufactures uses them. The ones I like and I think will be more effective on the XJ are installed just behind the radiator where the hot air from the cooling fan strikes the hood. That approach in my opinion would be the best approach to moving cool air through the radiator without passing it over the already hot engine or should I say passing less of it.

I have installed on my XJ more than 10 years a pair of electric fans, the fan controller is this, http://www.dccontrol.com/selector.htm, the 45 amp constant temperature version. and wired hot to the battery. The fans run when the preset temperature is reached and stops when thee coolant in the radiator (it have a probe in the radiator fins) is reduced. They cycles on and off for up to 30 minutes after the XJ is shut down. In South Florida, my XJ have not had heat soak since then. Even though the engine is not running, the temperature in the entire cooling system is reduced by simply moving cooler air through the radiator.