wiring up egt help

[lovejones]

So, close to putting n new engine, but few jobs to do before hand, i have a egt and boost gauge to put in (luckily the engines out as i cant get the exhaust off so have to weld whilst its in there), now i have the understanding of where and how to do the probe, quick question on this though, where do people run the probe line along in the engine, i was thinking along the firewall, and do people put a cable cover over it?

now in terms of wiring the damn thing, this is what i bought http://www.ebay.com.au/itm/PYRO-EGT-...sAAMXQVT9SsjN8

the instructions are terrible, to the point, on the probe i have blue wire and a white wire, on the gauge i dont have a blue wire yet the instructions state BLUE - CONNECT TO SENSOR BLUE, so there is problem 1. i have a set of 2 wire cluster, red and black, which i am assuming is power source and earth, then i have a cluster of 4 wires red, black, white and green.my guess here is,
Red for ignition
Black for battery negative (or another earth)
Green is for the blue
and white for the white

if anyone can shed some light on this with the vague info i have written, would appreciate muchly.

Cheers
Steve

[the evil twin]

One of the red/blacks may be for the instrument lighting.

Something is a tad odd about the colour codes for the Pyro
Green/White is usually for 1200 degrees K type thermocouple which makes sense as the gauge is a 1200 degree instrument (ideal for pre-turbo and OK for post Turbo)
Most people use a a J type thermocouple for post turbo which is 750 degrees but the colour code is usually White/Red
Blue/White is usually for an S or T type and not a colour code normally associated with J or K type.
But.......
There are a heap of different colour standards depending on country of origin of the thermocouples so maybe a question for the seller?

[GeeYou8]

Rule of thumb for thermocouple colour code:
The darker colour is positive unless it is red, then it is negative.
Connect up the probe, drop the probe in boiling water, an electric kettle won't shut off if the lid is open, it should read 100C.
Type K is the most common on thermometers & multimeters, it can be: green (+) & white(-), or Red(-) & yellow(+).
Graham

[the evil twin]

Yep, good rule of thumb for sure... the jap standard J type the Red is positive but no biggee

The boiling water idea might help on J type but is outside the range of K type.
A multimeter might help but the difference will only be about 2 or 3 mV so would need a good one.

[lovejones]

have tried contacting the seller, but no response.
all i could find was red to ignition
black to battery negative
blue (which i will assume is the green) to sensor
white to sensor

so will now think the red in the 2 cluster is batter positive (though i unsure why there would be two wires for power, being ignition and battery direct) and the black to the frame somewhere nearby for ground.

[the evil twin]

have tried contacting the seller, but no response.
all i could find was red to ignition
black to battery negative
blue (which i will assume is the green) to sensor
white to sensor

so will now think the red in the 2 cluster is batter positive (though i unsure why there would be two wires for power, being ignition and battery direct) and the black to the frame somewhere nearby for ground.

As prev posted... does the gauge have lighting?
If so there is a better than 50 chance that will be the other red

[lovejones]

yer sure does, i hooked it upto a battery with just red and black pair and light comes on. tried with the red and black in cluster of four and nothing happened, so guessing the 2 reds are power 1 black negative, one black earth, the other two connecting to the probe.

[Hodge]

Yep, good rule of thumb for sure... the jap standard J type the Red is positive but no biggee

The boiling water idea might help on J type but is outside the range of K type.
A multimeter might help but the difference will only be about 2 or 3 mV so would need a good one.

You seem to know about the thermocouples ET (and every other electrical thing), so I've got a quick one for ya here instead of starting a new thread...

I've had this little numerical EGT readout thingamajig for a while. It reads K type thermocouples... My existing Redarc setup is K type.
If I hooked up the numerical one in parallel (spliced into the red and yellow wires), would it work ? I'd like to have a numerical readout of EGT's along side of my Redarc gauge.
The numerical unit has a calibrate function on it too so it has some adjusting capability.
Photos below are of the unit, it's description and a snippet from redarcs specs of the Thermocouple currently in my dump pipe.


Sorry about hijacking the topic slightly lovejones.

[the evil twin]

Uummmm... depends on a couple of things but usually works OK (in the ranges and accuracy we are interested in anyway).

Dont 'splice' into the Thermocouple wires.
Just try connecting from the terminals of the existing gauge to the K+ and K- of the digital gauge.
Use light gauge copper wire not thermocouple wire to go from the existing EGT gauge to the Digital one (pins 3 and 4).

[Hodge]

Thanks ET. When I said splice (bad terminology on my behalf) I really meant just piggy back it into the current thermocouple plug together with the thermocouple wires already existing . Rough drawing below. I already got some very low profile copper wiring ready to go.