Oil PSI light, H20 temp light?

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Cope

Fusing with fire
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Im thinking about adding a oil psi light and just looking at kits and such it look like i can just about buy any pressure sending unit and T it off my gauge.

my guestion is would the single wire on the sending unit be ground? and hot to the light?

Thanks.
 
I have an autometer gauge but I want an idiot light also just incase..

what PSI would be considered low?

also i want a temp light, H20 temp idiot light should the light come on, 220? I run around 190 in traffc.

Thanks.
 
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I believe the sender is self grounding. So only one wire. Im not sure if they can both function from the same sender??
I have an autometer as well but its mech style.
I would think min 25 psi and yer good. Dads never gets below 40
 
yes the sender is grounded but the sender is not a hot wire? correct?

so hot wire to light, ground to sender?

my.plan is to run dual sending units, one for the light and one for the gauge.
 
Run coolant water at 50/50 and 220 should be ok.
I have autometer water temp and oil psi aftermarket mounted on lower edge of dash. we left factory gauges in dash as we like stock look. The gauges worked but they are still almost 50 years old.
 
For me the coolant sensor has only one wire to it. I cant remember how many wires go to gauges.
Chk autometer website out for the wiring?
 
Run hot to the light on one side and the switch to the other side from ground, yes. The PSI ranges from 3-7 to cut the light on.
 
ok so who makes a sending unit that trips/opens at 3/7 PSI?

and 220 degrees is ok for H20 temp?
**** what is to hot, i get worried around 210....
 
Ok, ok..
Thats what i thought. any generic sending unit and a raidio shack 12v light should work.

what about H20 temp sendimg unit?
 
i run a small amount of antifreeze and water weter. so 210 is to hot?
 
I did the same thing for my dart....guage plus lights.
Here's the sender I used:Oil Pressure Switch - W/ Light-440 Source

I used little LED flush mount bolt lights from here: Flush Mount LED Bolt | Oznium They're bright at ****, so wired in a 3Kohm resister inline with them which reduced them perfectly. Flush, clean little lights. Above poster is correct....the sender is self grounding.
 
You can get a temp switch at just about any range you want.
 
No 210 is not too hot. Not even for plain water. Rememper the system is under pressure.
 
You can also get adjustable switches and set it for whatever pressures you want it to come on at.
And yes, keyed power to the light and the sender grounds it when the pressure is too low.
Basically what happens is the light would come on when you turn the key on and then go off when your oil pressure came up.

Just an FYI, you can do exactly the same thing with buzzers for an audio warning.
One of my cars had all three (gauge, idiot light and a buzzer) for oil pressure, temp, and charging system.
I had a switch that you could turn the buzzers off or on with if you didn't want audio and just gauges with idiot lights.

Not to long ago on here we discussed how to make the gauges and speedometer backlighting all turn red instead of an idiot light.
That was pretty cool also.
 
Also, if you are crafty, you can use something like your brake light for the temp warning. "You just have to remember". The brake light is already all hooked up. Just tie into the brake switch wire and run it over to the temp or sender.

However, remember you must actually get the correct sender. They MUST be for a lamp and not a gauge.

GM or Ford, can't remember, did this "awhile back," remember? They had an "engine warning lamp" It was branched off to BOTH the temp an oil, one light did two jobs.
 
Also, if you are crafty, you can use something like your brake light for the temp warning. "You just have to remember". The brake light is already all hooked up. Just tie into the brake switch wire and run it over to the temp or sender.

However, remember you must actually get the correct sender. They MUST be for a lamp and not a gauge.

GM or Ford, can't remember, did this "awhile back," remember? They had an "engine warning lamp" It was branched off to BOTH the temp an oil, one light did two jobs.

Yep, lights use and on/off type sender switch and gauges use a variable voltage rheostat type sender.

Heck you could even make something that yelled "AAAAAHHHHH, NO OIL PRESSURE!" :D
It' all just control switches and something that reacts when switched.
 
Pressure switch? Hobbs. Temp should be at the lowest abnormal temp for that engine. If it never hits 200° set it for 200 not 210 or 220. If the light comes on ocasionally during normal use,thats okay cause it tells you to keep watch on it. Thats my opinion.
 
And the big caveat; gauges and lights only work if you are looking at them. If your eyes are on them, who is driving? I like to drive, so no gauges here....... Well, I have; a speed-O, and a tach.
Once in a while I look at the tach.....
But the Speed-O is my friend. It saves me buckets of money.
 
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