The Grand Rapids Technologies 4000 EIS has and adjustable alarm for denoting when the difference between the lowest and highest EGT's exceeds a user defined limit. I've got mine set at 265. Over the years, I'd get an occasional alarm but lately it's been more frequent. In the cruise mode yesterday at a MP of about 24 or 25, I checked the EGTs several times and they were typically 1270 (left front), 1390 (right front), 1457 (left rear) & 1475 (right rear). Oil Temp was 160 and CHTs were 295, 331, 311 & 296 respectively. Later on, as I lowered MP slightly for a gradual descent, my EGT's came closer together at 1422, 1481, 1454, 1486.
I don't think I've got a problem and I've got an annual due in a little over a month, but my question is...If I have a compression issue in #1 cylinder, would the EGT go down or up? Intuitively, I'd think that the lower the compression....the lower the EGT, but then I also think I remember hearing somewhere that if a valve is leaking, the EGT goes up.
It's been a long time since I did any reading on engine operating characteristics & EGT's and I need a little refresher. When my EGT Span Alarm has gone off, by increase the leaning I've raised all EGT's but the #1 cylinder EGT would increase slightly more than the others to get the span within range to turn off the alarm. Before I spend too much time worrying about a possible problem, I thought I'd check if this might be one of those "quirks" that RV's can have.
Thanks
Rick Luck
RV9A N109RV
0-360D1A 275 hrs
const speed prop
I don't think I've got a problem and I've got an annual due in a little over a month, but my question is...If I have a compression issue in #1 cylinder, would the EGT go down or up? Intuitively, I'd think that the lower the compression....the lower the EGT, but then I also think I remember hearing somewhere that if a valve is leaking, the EGT goes up.
It's been a long time since I did any reading on engine operating characteristics & EGT's and I need a little refresher. When my EGT Span Alarm has gone off, by increase the leaning I've raised all EGT's but the #1 cylinder EGT would increase slightly more than the others to get the span within range to turn off the alarm. Before I spend too much time worrying about a possible problem, I thought I'd check if this might be one of those "quirks" that RV's can have.
Thanks
Rick Luck
RV9A N109RV
0-360D1A 275 hrs
const speed prop