I have been having high indicated oil temps with my newly finished RV-7. I have the Garmin G3X. All other engine indications are normal.
I have the Aerosport IO-375 with 9.5-1 compression, and after searching here have found that others with this engine have also sometimes had temp issues.
We have checked the vernatherm. I even replaced it just to be sure, with no change.
Today we wired up a steam gauge to a separate probe to see if it was an indication problem. The results were interesting.
The engine has about 42 hours on it now.
At 74% power, 25" at 2300RPM, 3400' MSL, 66 degrees OAT, leaned 170 degrees rich of peak this was the result:
CHT's: 356 357 338 341
EGT 1235 1205 1205 1200
Oil pressure: 67 psi
Garmin oil temp 225, steam gauge temp 205
I tried it again at WOT, 90% power 27.3" at 2630 RPM, full rich mixture
CHT's 358 369 338 342
EGT 1215 1185 1180 1180 (maybe a different injector for #1 is in order)
Oil pressure: 65psi
Oil temps: Garmin 239, steam gauge 218
So a twenty degree difference between the Garmin and the steam gauge.
I have a 9 row cooler and am thinking of going to a 12 row from Airflow Systems, but I have two questions:
#1) How to tell which gauge is the more correct gauge?
#2) Is there a way to recalibrate the Garmin gauge if it is the one reading too high?
I have the Aerosport IO-375 with 9.5-1 compression, and after searching here have found that others with this engine have also sometimes had temp issues.
We have checked the vernatherm. I even replaced it just to be sure, with no change.
Today we wired up a steam gauge to a separate probe to see if it was an indication problem. The results were interesting.
The engine has about 42 hours on it now.
At 74% power, 25" at 2300RPM, 3400' MSL, 66 degrees OAT, leaned 170 degrees rich of peak this was the result:
CHT's: 356 357 338 341
EGT 1235 1205 1205 1200
Oil pressure: 67 psi
Garmin oil temp 225, steam gauge temp 205
I tried it again at WOT, 90% power 27.3" at 2630 RPM, full rich mixture
CHT's 358 369 338 342
EGT 1215 1185 1180 1180 (maybe a different injector for #1 is in order)
Oil pressure: 65psi
Oil temps: Garmin 239, steam gauge 218
So a twenty degree difference between the Garmin and the steam gauge.
I have a 9 row cooler and am thinking of going to a 12 row from Airflow Systems, but I have two questions:
#1) How to tell which gauge is the more correct gauge?
#2) Is there a way to recalibrate the Garmin gauge if it is the one reading too high?