EGT explination please.
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EGT explination please.
I am still new to the diesel world so I am kind of ignorant on egts. I understand what they are and why you do mot want high ones but what causes high egts?
I have a pyro gauge now so I watched it the last couple of days with my new turbo and it seems like higher rpms yield lower egts. I would think the oppisite but I dont know. Lugging it seems to gain egts
How can you control egts? I know with your foot but if how do you control them? If they get hot should I drop a gear and raise the rpms or what? Thanks and sorry for a newbi question but I searched and did not find my answers.
I have a pyro gauge now so I watched it the last couple of days with my new turbo and it seems like higher rpms yield lower egts. I would think the oppisite but I dont know. Lugging it seems to gain egts
How can you control egts? I know with your foot but if how do you control them? If they get hot should I drop a gear and raise the rpms or what? Thanks and sorry for a newbi question but I searched and did not find my answers.
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Joined: Jan 2001
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From: Poway, CA
Pretty much it. Easiest way to think of it is how hard you a working the engine. Like a gasser, a diesel will work harder (you have to put your foot into it more) at lower revs, especially when under a load like towing or going up a hill. Let it wind out a bit, make life on it easier, and you'll make it a much happier truck. It's tempting to let it lug up hills without all that low-end torque, but it's actually happier up against the governor than chugging down low. Being fairly new to diesels myself, this was something I had to learn, too.
Mike
Mike
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From: NW Ga
Air to fuel ratio is the whole key.
Lugging it gains egts because when your lugging your engine like when pulling you are pushing the pedal down and applying more fuel but not increasing the rpms so you can have twice the amount of fuel going into a cylinder and twice the heat coming out. but without the rpms the heat is not being pushed out the tail pipe as fast. In sort you have a higher fuel to air ratio.
The reason it doesn't heat up when you just have high rpms is because you have basically the same air to fuel ratio, Its just going in and coming out faster. It takes only a small amount of fuel to keep the engine at a higher rpm compared to that of when your just driving around.
Heavy on the pedal compared to low rpms equals heat
Lugging it gains egts because when your lugging your engine like when pulling you are pushing the pedal down and applying more fuel but not increasing the rpms so you can have twice the amount of fuel going into a cylinder and twice the heat coming out. but without the rpms the heat is not being pushed out the tail pipe as fast. In sort you have a higher fuel to air ratio.
The reason it doesn't heat up when you just have high rpms is because you have basically the same air to fuel ratio, Its just going in and coming out faster. It takes only a small amount of fuel to keep the engine at a higher rpm compared to that of when your just driving around.
Heavy on the pedal compared to low rpms equals heat
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gotcha, I drove mine on the hwy today with the new turbo and watched the egts. I did notice the egts are way higher on the back roads than doing 70 on the hwy so it makes sense that you are low in the rpm band and when you add more fuel to speed up it makes the cylinder hotter but its not scavenging as well . Thanks guys.
My egts ranged from 500 to a 1000 max but usually stopped climbing around 900 so I think I am in a good range.
My egts ranged from 500 to a 1000 max but usually stopped climbing around 900 so I think I am in a good range.
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