Steve Saunders Goldwing Forums banner

81 - 89 of 89 Posts

·
Administrator
Joined
·
26,539 Posts
I believe you are thinking combustion temp, Dave. He is talking exhaust gas temp.:)
Yes, it becomes the same thing. I use an IR temp gun on 4 cyl wings exhaust to adjust the idle mixture.
 

·
Premium Member
Joined
·
6,828 Posts
Yes, it becomes the same thing. I use an IR temp gun on 4 cyl wings exhaust to adjust the idle mixture.
If the mixture starts too rich and you lean out the mixture EgT will rise because you are making more power. Not to the point of glowing red but up to normal temps. After EGT peak the temps will start back down as now you have crossed stoichiometric ratio.(you would start to make less power if you lean the engine out any more) At this point it has been my experience that the pipes might glow slightly especially near the bend where they come out of the cylinder head if they are thin.
If you start with an engine that is too rich and you lean it out the EGT will rise, then peak and fall as you lean it out more. About peak temperature the power (energy) starts to drop and so does the EGT. I have seen this many times.
Red hot exhaust (lots of it) is usually caused by late timing. By far the most popular reason with non-catalytic cars..
When the timing is to late the fuel burns so slow there is still fire when the exhaust valve opens. You essentially have a flame thrower for exhaust. :) . .And of course no power because no "bang." :cool:
.
 

·
Administrator
02 GL1800 w/Auto Pilot
Joined
·
60,154 Posts
If you start with an engine that is too rich and you lean it out the EGT will rise, then peak and fall as you lean it out more. About peak temperature the power (energy) starts to drop and so does the EGT.

.
That is how good airplane pilots tweek out the fuel mixture when leveled off and trying for best fuel performance.

Slightly lean gives good power, with less fuel flow.
Airplanes have EGT gauges so it is easier to monitor that condition.
 

·
Administrator
Joined
·
26,539 Posts
If the mixture starts too rich and you lean out the mixture EgT will rise because you are making more power. Not to the point of glowing red but up to normal temps. After EGT peak the temps will start back down as now you have crossed stoichiometric ratio.(you would start to make less power if you lean the engine out any more) At this point it has been my experience that the pipes might glow slightly especially near the bend where they come out of the cylinder head if they are thin.
If you start with an engine that is too rich and you lean it out the EGT will rise, then peak and fall as you lean it out more. About peak temperature the power (energy) starts to drop and so does the EGT. I have seen this many times.
Red hot exhaust (lots of it) is usually caused by late timing. By far the most popular reason with non-catalytic cars..
When the timing is to late the fuel burns so slow there is still fire when the exhaust valve opens. You essentially have a flame thrower for exhaust. :) . .And of course no power because no "bang." :cool:
.
Thank you professor Mike. I can't think a string that long much less remember it long enough to type it.
 

·
Premium Member
Joined
·
6,828 Posts
Thank you professor Mike. I can't think a string that long much less remember it long enough to type it.
It is not that difficult Dave. If an engine is rich and you lean it out EGT will peak near maximum torque or HP. If you continue to lean it out temps will drop. As energy increases so does EGT. Easy peasy. Check it out. :)
 

·
Premium Member
Joined
·
6,828 Posts
Here is a video that shows and explains it better than I can. Hope it helps.
 

·
Administrator
Joined
·
26,539 Posts
It is not that difficult Dave. If an engine is rich and you lean it out EGT will peak near maximum torque or HP. If you continue to lean it out temps will drop. As energy increases so does EGT. Easy peasy. Check it out. :)
I know, I was just commenting on your lecture.
 
81 - 89 of 89 Posts
Top