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Topic: another wiring question. (Read 3177 times) previous topic - next topic

another wiring question.

Reply #15
Quote from: jcassity
tom,,,,any comment on my second and third comment up there?


I'll just add this...

For the relay you need a HEAVY DUTY type that will handle 30+ amps if you don't want to burn it up in a few days. Few if any relays used in our cars will handle that much current...

You'll need a different type sender as the resistance of the gage unit is variable and probably won't activate the relay coil till the engine is too hot. Also it should be a different sender than the gage is connected to. As it will feed back through the relay coil and likely read high contunally....

Basially you'll have far fewer potential problems if you just install all new wiring. BE SURE to use at least #10 or larger to feed the relay and fan... The size of the wire from the controller or switch to the relay coil ain't a issue...

another wiring question.

Reply #16
Almost sounds like Id be just as well off buying a kit for installing an electric fan that has the relays and stuff in it then. Thanks everyone for the help. Time to start shopping for fan stuff
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.

another wiring question.

Reply #17
You can not use a viariable resistance ground for the relay.  It will cause it partially engage and burn it up.  Kinda like holding a house light switch at a certian position half way in its throw.  You can see the light flicker and the switch will sizzle like bacon.  You don't want the same to happen to your relay.
 
I got my fan controller from autozone.  cost me like 24 bucks I think.  I do not like the probes that go into the slots in the radiator, but it does function rather well.
 
And a third thing.  I have dual cooling fans and a 3 core radiator.  This past winter I had to unplug one of the fans so that I would have heat.  The guage would run nearly to the bottom.
One 88

another wiring question.

Reply #18
Quote from: CougarSE
This past winter I had to unplug one of the fans so that I would have heat. The guage would run nearly to the bottom.

The guage on mine hardly got above the bottom letter on the word norm while the car was running for a long period of time I shouldnt have that problem but now that you said that its got me wondering if I'm going to have that problem.
I didnt turn the heat on it was like 90 out but it didnt get very high on the guage.
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.

another wiring question.

Reply #19
Master_xzavior
Ok,, i got around to testing this out over the past few days off and on and evidently, the resistance of the temp sensor does not decrease in resistance quickly enough to give the relay a ground.  You would be near an overheating situation by the time the sensor reached the resistance required for the relay to get a ground.

so,,,,,,,it would work fine if the sensor were a little different but we live with what we have.

I did have sucess like CougarSE using a thermal couple or the variable resistance switch to activate my relay.  I had a normally open temp switch that use to be in a space heater of my garage.  Its temp range seemed to be about 200 deg judging from the part number.  It was held in place by two rivits but anyway, i mounted this switch on the radiator below the upper hose. 
I wired up a large headlamp to the contact side of the relay and put the thermal switch in line with the relay coil ground.  The relay clicked on when my needle was about 5/8 to 3.4 the way on my cluster.

another wiring question.

Reply #20
well with my guage barely hitting the lower letters I need to actually find out what temp my motors running at when the needle quits going up. the cars pretty much stationary right now with my other wiring problems and such. I swear whoever said the wiring on these cars is simple needs smacked or something :D this things turning into enough of a pain Im seriously considering selling the car even though I know Id kick myself in the ass for it later on.
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.

another wiring question.

Reply #21
evidently,, either your sensor is bad or the needle is out of calibration and possibly the voltage regulator that creates 5vdc in the dash cluster.  there's not much to the cooling circuit at all.

another wiring question.

Reply #22
well my fan runs constantly at the moment unless I put a toggle in it. Im wondering if maybe its not cooling to much. If I recall right though the fan was in a honda car so I wouldnt think it would cool a 302 that much but I could be wrong.
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.

another wiring question.

Reply #23
http://www.hoffind.com/thermal.htm
experiment with one of these switches.  Google "thermal switches".  THey are cheap, durable and last a long time.  You must find one that is normally open "N.O." and is rated to close at your desired temp range.  Id suggest one that closes at 200 and resets at 180 or there abouts.

you can just mount this device anywere that allows the flat part to be touching areas that get hot on your engine bay,, try different locations on the engine to activate the switch.  you can find these in different things people end up throwing away. Put this in line with the ground lead of your fan and it will come one at the correct time.

how did you end up wiring your fan up anyway?

another wiring question.

Reply #24
I grounded it to the radiator support and ran the other end to a hot with the key on. So basically if the keys on the fans on.
Which this way would be fine if I had a fan controller that slowed it down to where its not cooling at full capacity.
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.


another wiring question.

Reply #26
are you talking about the piece that screws into the tank itself or the control box itself?
87 T-bird two tone diarrhea color. 5.0 converted with AOD.  GONE BUT NOT FORGOTTEN
 
94 Lincoln Towncar, Dark Metallic Green, 4.6L AOD
SOLD!!!!
 
99 Mercury Cougar. V6 MTX75 Trans. CURRENT PROJECT DAILY DRIVER.


 

another wiring question.

Reply #28
Dredging this back up.
ipsd, how is that controller working out?  Still strong?
I'm worried about the draw on it.  It says it's rated for 30 amp, but don't the fans draw near 100 on start up?  Or is the 30 for continuous draw?
1988 Thunderbird Sport (1st car)
351W in the works
"I'll get it one piece at a time...":D

Quote from: bhazard;300566
You got woman'd.