Thermos

[InitialD]

Ive had the EL thermo's in the car for a while now and have noticed that they are ****ing me off.

They seem to come on ALOT at idle, they are draining the #@$!! out of my battery and no matter what I do still does it. The same wiring on John_xr6's ED and Dellboy's EA doesnt have this issue. The Volt gauge is showing 13 and slowly drops to 12, this is shown also on the Multimeter when I check it at the battery and Alternator. Tonight it was the last straw when it went UNDER 12 volt!

Ive EVEN tried different alternators and even a new battery!

Will I loose any power if I go back to the trusty Clutch fan?

[INJECTED_250]

Where are the fans getting there power from.. IS the earth and power straight to the battery via a relay of course, With the trigger just earthing the realy... I found this was the best way, i used to just have the fans getting a ground from the body, i found drawing 40-60 amps on startup wasnt a good idea through body earths.

[InitialD]

Originally Posted by INJECTED_250

Where are the fans getting there power from..

The fans are getting there power from the back of the alternator.

IS the earth and power straight to the battery via a relay of course, With the trigger just earthing the realy...

Yes thats the way it is wired. Both from the battery

The fans are wired up exactly how specified via the "craig davies twin thermos" wiring diagram

[LTDHO]

Check all your earths. It sounds silly but a fans are running past the cars limits and the linit may be somewhere else.

Make sure the earth from the battery to the chassis is good. Clean the terminals on the battery and the terminal on the chassis. It is good to remove paint.

[INJECTED_250]

have u tried the fan power directely from the battery and not the alternator?.... not sure if it would make a differnce

[Sox]

The fans should be getting power from the battery, not the alternator.

Also, the fans are supposed to come on when the engine is idling, as that is when they are needed most.

BTW, 'INJECTED250' earth should be left via the chassis, 40-60amps is nothing, how much current do you think the starter motor draws....

Rick.

[LTDHO]

The alternator runs the car, not the battery!

It make no difference whether you wire it to one ot the other as they share posative. Unless the wire between is to small. I upgraded mine to 8G.

You will find the fans aer not the problem, but they are showing it. Find the fault first.

[Shonky]

Have you tried re-adjusting your thermatic switch?

[Sox]

Originally Posted by LTDHO

The alternator runs the car, not the battery!

It make no difference whether you wire it to one ot the other as they share posative. Unless the wire between is to small. I upgraded mine to 8G.

I realise that, that's why I said to wire to the battery, as that may help determine if the alternator is running out of puff, or the wire is too small.

Rick.

[LTDHO]

Originally Posted by Sox

I realise that, that's why I said to wire to the battery, as that may help determine if the alternator is running out of puff, or the wire is too small.

Rick.

Whilst I am convinced the fault in not the fan. A simpler test to check if the wire it to small.
Check power at alt and at batt using batt neg with fans on. There should be no difference in voltage.

Changing the wire for the alt to the bat will not show if the alt is 'running out of puff'.

[Sox]

Originally Posted by LTDHO

Whilst I am convinced the fault in not the fan. A simpler test to check if the wire it to small.
Check power at alt and at batt using batt neg with fans on. There should be no difference in voltage.

Changing the wire for the alt to the bat will not show if the alt is 'running out of puff'.

Perhaps not, though fans can draw more 120amps on startup and can maintain 30-60amps depending on there speed/type.

I'd prefer to see this connected directly to the battery, as that's where the least resistance to large current will be.

Rick.

it could be the fans are getting old ???

[InitialD]

Originally Posted by LTDHO

Check all your earths. It sounds silly but a fans are running past the cars limits and the linit may be somewhere else.

Make sure the earth from the battery to the chassis is good. Clean the terminals on the battery and the terminal on the chassis. It is good to remove paint.

Ive checked the negative connections allover the enginebay. Ive also ran new negative wiring from the thermos themselves to the battery.

The wierd thing is while the car is actually in motion (driving around) there is NO voltage drop but soon as i am about to stop the voltage drops? Almost like the thermos are not draining as much current when they are being assisted in moving via the wind? or is that just a stupid idea... :

When the car is actually not moving i have to do 1500rpm for it to charge at 14v. The Alternator is reco and ive tried 2 other ones aswell.

[Sox]

Originally Posted by InitialD

Ive checked the negative connections allover the enginebay. Ive also ran new negative wiring from the thermos themselves to the battery.

The wierd thing is while the car is actually in motion (driving around) there is NO voltage drop but soon as i am about to stop the voltage drops? Almost like the thermos are not draining as much current when they are being assisted in moving via the wind? or is that just a stupid idea... :

It doesn't work like that, it's normal for volts to drop as rpm drops as the alternator isn't being spun as fast.
Alternators only produce peak current at 1500rpm or so.

When the car is actually not moving i have to do 1500rpm for it to charge at 14v. The Alternator is reco and ive tried 2 other ones aswell.

Yep, normal.
Has the battery actually gone flat, or are you just worried about the gauge reading low?

Rick.

[Damo]

put ya clutch fan back on. :P They rock!

[InitialD]

Originally Posted by SOX

Has the battery actually gone flat, or are you just worried about the gauge reading low?

It has actually gone under 12v the other night, and it at idle is showing lower then normal. The car is also harder to start now... Ive tried another battery and it made no difference

[INJECTED_250]

Originally Posted by Sox

The fans should be getting power from the battery, not the alternator.

Also, the fans are supposed to come on when the engine is idling, as that is when they are needed most.

BTW, 'INJECTED250' earth should be left via the chassis, 40-60amps is nothing, how much current do you think the starter motor draws....

Rick.

Um..... The starter dont get its ground from the body earths rick?..... last time i checked it was that nice thick black cable running from the battery, which does go to the body then to engine , but the connection with the body earth is irelevant to the cranking current.

But if all is good there is no problem using the body.. as long as the earths from the body to the battery are nice and chunky and connected .. it

[Sox]

Originally Posted by INJECTED_250

Um..... The starter dont get its ground from the body earths rick?..... last time i checked it was that nice thick black cable running from the battery, which does go to the body then to engine

LOL, think about what you just said.

Question for you, is there a earth cable going directly from the starter to the battery?
If not, where is earth for the starter coming from.

Hint: Read what you wrote above.

Rick.

[Sox]

Originally Posted by InitialD

It has actually gone under 12v the other night, and it at idle is showing lower then normal. The car is also harder to start now... Ive tried another battery and it made no difference

Yes, it will show lower than normal, as there is a much extra current drain due to the electric fans, this is normal.

However, has the battery gone flat, or has it been unable to start the engine?

Rick.

[INJECTED_250]

Originally Posted by Sox

LOL, think about what you just said.

Question for you, is there a earth cable going directly from the starter to the battery?
If not, where is earth for the starter coming from.

Hint: Read what you wrote above.

Rick.

UM YES there is rick, its one continual length of wire, there for the direction of current is along this wire not through the body.
If this swaged join is un bolted from the body it will still crank fine rick so i dont see how u figure engine is earthed through the body then to the battery which is what u are saying. This would require 2 seperate lengths of wire connected to 2 differnt points on the body one from the starter tothe body then one from the body to battery in differnt locations to flow any current under crank between these to points . as you can see rick this is not the case enjoy :>


..

[Sox]

Originally Posted by INJECTED_250

UM YES there is rick, its one continual length of wire, there for the direction of current is along this wire not through the body.
If this swaged join is un bolted from the body it will still crank fine rick so i dont see how u figure engine is earthed through the body then to the battery which is what u are saying. This would require 2 seperate lengths of wire connected to 2 differnt points on the body one from the starter tothe body then one from the body to battery in differnt locations to flow any current under crank between these to points . as you can see rick this is not the case enjoy :>


..

Ok, you're missing the point.
Yes, in this instance, the manufacture has used a continuous wire from >battery>chassis>engine.
However, the chassis is still the common ground point.

Think of cars with an earth strap running from the engine to the chassis.
Think of boot mounted batteries.
Think of trucks where the batteries are mounted meters away from the engine.
In all of these instances, a long positive feed runs from the battery to the starter (or more usually, a junction).
And the negative from the battery takes the shortest path to the chassis.
The engine block then has an earth strap.
Earth is not run to the engine block in these cases, and of course is not needed.

I know what you're saying, but that's doesn't change the fact that the best earth for the electric fans will be chassis, not the negative battery terminal, as this just creates an unnecessary long wire.

Rick.

[LTDHO]

Originally Posted by INJECTED_250

..

This is the earth that needs to be upgraded. The connection to the chassis run the car, the loop to the engine runs starter, sendors and alt. This wire has to be at least the size of all the wires from the posative!

[InitialD]

Originally Posted by Sox

Yes, it will show lower than normal, as there is a much extra current drain due to the electric fans, this is normal.

However, has the battery gone flat, or has it been unable to start the engine?

Rick.

NO but the battery has gotten really LOW to a point where ive had to charge it up. I'd rather work out WTF is going on now before i am stuck somewhere with a dead battery _2:

[Rmyers]

Time for a serpentine belt drive conversion :P

[galapogos01]

i never needed both fans to come on to keep my car cool. and i had a old radiator. try using one with the aircon, one with the thermoswitch.

[InitialD]

Originally Posted by galapogos01

i never needed both fans to come on to keep my car cool. and i had a old radiator. try using one with the aircon, one with the thermoswitch.

I was actually thinking about this tonight on the way back from shopping, that I could run it like a EF/EL. Have one come on via the thermo switch at one temp and somehow have the other come on at a higher temp. But this would mean i need two switches correct?

I thought maybe of having one of the thermo's running off a switch on the dash, so if the one fan cannot do enough, I can simply switch the other on.

If i was to do it this way, what fan would you recomment comes on first? the inlet or exhaust side?

[InitialD]

Rollin

Alternator belt is fine and tight, i ONLY have voltage lost when the thermo's are on.

Cooling system appears to be fine (new thermostat, water pump, flushed radiator and has new coolant)

[galapogos01]

i never needed more than one fan in the 4 years i had my EA.

you should have one wired to the aircon anyway, because you risk high system pressures and blowing up your compressor if you let the condensor get too hot.

Jason

[redspak]

run brand new + and eaths to ur thermos, tap into ur brake light switch on ur pedal, and weneva u brake the thermos will come on, that way if u stop there isnt wind to go thru the radiator, but wen u stop u are sending power to the thermos turning them on, will keep ur car cool and u should experience the voltage drop, the voltage drop is caused by too much resistance in the wires, so if u dont wanna wire them up to the brake like feed then run ur earth the same size as ur + or replace both wires as they could be corroded.

[clampy]

what speed does your car idle at? what is the amp rating of the alternator? (alternators have a regulator in them so that they wont charge till over a certain rpm.)

i have no idea why people are raving on about the earth wires to the thermos. check the positive wire from alternator to battery tho. or it could just be that you've got an older alternator that literally cant produce that kind of current.

heres a test, get car to idle with thermos on.. then put the lights on, highbeam too... does the voltage drop even more/faster? if so then your alt is probably too small.