EGT Gauge - What readings should it be and what to look out for?

[Xtreme]

Today I had an EGT Gauge and boost gauge installed. The boost runs about 18psi is that pretty normal?

I was in a hurry and got a mechanic to help me out and install the EGT Gauge, I had to run at the end of it and so he could not get the motor up to temp to test it all as the gauge starts at 300 deg C. Running home up the freeway on 110 the needle never left the 300 mark (as in it stayed at zero reading movement). From what I understand I should be concerned if the temp reaches 500 and worried if it hits 550-600 as that is when damage can occur?

I was wondering what is the normal operating temp I should expect to see is it less then 300 Deg C? or is my new gauge faulty? is there a test I can do to check if the gauge or sensor is working correctly?

[Mud Gecko]

What gauge mate? Lots of boost = low EGTs. To check if the gauge is working, hold her flat in 4th until you see the gauge move?

[Hodge]

Mate if I understood correctly, your gauge doesn't show temps below 300C ? The gauge should definitely be going below 300C. Even on very hot days they should be idling at around 150-200C. In terms of high temps, every car behaves differently. 500-600 isn't unheard of, but you shouldn't let it stay there for long. The important thing is that the temps come down afterwards.

[mudski]

Your gauge should start at zero. Dud gauge it looks like.

[Hodge]

What gauge do you have anyway? Some of them can be calibrated. Maybe your needs to be.

[the evil twin]

Is it a mainstream brand gauge and thermocouple.

Post up a link or piccy to your gauge. Pyro gauges come in all sorts of ranges. The best one for your truck is zero to no more than 200 at the low end to 1200 preferably but no lower than 1000 or more than 1400 high
Having said that 300 Celsius as a bottom end is a bit of an odd one... the only one I am familiar with like that is the Autron (275 to 800 C) dual jobbies who use a compressed scale so they can fit two analog displays on the 52mm dial

Are you sure it isn't a farenheit gauge?

... aaand are you sure it is a K type thermocouple with the closed sensor head

[the evil twin]

Also... if you are in a hurry it is easy to get the wires wrong on the sensor.
If it is a yank colour code then Yellow is Pos and Red is Neg
If it is another colour pair post up and I'll tell you... or... just swap 'em and try it... it won't hurt anything

[Xtreme]

Thanks for the input guys, turns out that on the connector that goes into the back of the gauge on one of the pins there was no wire for the last 2 inches :S the gauges I bought are both SAAS so i thought they were a half decent brand - not the dearest, but not the cheapest, they were the best I could afford at the time.

After fixing that the gauge now still stays not moving off 300 but occasionally it has gone a few times to 420 lugging 2700kg up a hill so I guess it is working. It goes from 300 to 14oo C. When I have some money again I will get one that starts from zero but at least this one will let me know if its getting dangerously high. I think it was on patrol 4x4 that I read not to let it get over 550-600 as that is when it can crack/melt a piston

[the evil twin]

Thanks for the input guys, turns out that on the connector that goes into the back of the gauge on one of the pins there was no wire for the last 2 inches :S the gauges I bought are both SAAS so i thought they were a half decent brand - not the dearest, but not the cheapest, they were the best I could afford at the time.

After fixing that the gauge now still stays not moving off 300 but occasionally it has gone a few times to 420 lugging 2700kg up a hill so I guess it is working. It goes from 300 to 14oo C. When I have some money again I will get one that starts from zero but at least this one will let me know if its getting dangerously high. I think it was on patrol 4x4 that I read not to let it get over 550-600 as that is when it can crack/melt a piston

Glad you got it working OK however I'm curious what engine is in the vehicle?

As you say, the gauge will work as good as any for operating EGT's and to stop you exceeding safe levels.
The biggest advantage of one with a lower "zero" than 300 is so you can see what the EGT's are prior to shutdown.
Personally I let my CRD idle down and don't switch off if my EGT's are above 200 so the oil doesn't coke in the turbo but that is a personal preference.

[Stropp]

Personally I let my CRD idle down and don't switch off if my EGT's are above 200 so the oil doesn't coke in the turbo but that is a personal preference.

yep me too just to be on the safe side.

[Xtreme]

The motor is a 2000 ZD30 not CRD, has done 245k, seems to be going strong, have just finished doing all oils and filters in the car including the diffs, transmission and everything else, dawes valve installed, 3 inch exhaust put on, EGR Blocked, pretty much everything I can think of to make it as reliable as possible. Have just installed a Roo systems pre programmed chip - makes a bit of differenece and this is what I see with it:

If I am trying to accelerate and the turbo has not switched on the EGR's climb rapidly, as soon as the turbo kicks in they fall just as rapidly.

What I assume is that the Chip is pumping in Fuel to increase power when turbo is not on hence the higher EGR readings and then it backs off when the turbo kicks in