swisseagle
Well Known Member
Hello
My buddy has a RV-7A with an Aerosport IO-320, turning an Sensenich metal FP since about 200 hours. The fuel injection is a Silverhawk unit.
He told me a few times that something seams not as it should be. I looked at the data and do not get the cloue what it can be really.
I told him to make a GAMI spread, here the results:
The spread is in liters, here the equivalent in USG:
24.5L = 6.47 USG
22.0L = 5.81 USG
21.0L = 5.54 USG
After this, he cleaned the nozzle 1 and 3, but this did noch changed the situation.
I think we contact Don Rivera and get other nozzles.
One other thing, I found, when he is leaning, the cylinder 3 CHT drops by about 40 to 50?F, the others stay together more even. When he enrichen the mixture, cylinder 3 CHT comes back quickly!?
Picture when cyl 3 CHT drops (EGT top row, CHT bottom row):
And here when it comes back (cyl 3 is yellow here):
Does he run it too lean, so that cyl 3 is allready on the lean side of the peak? Here he has it at about 25L (6.6 USG) and past time 00:10 at 28L (7.3 USG).
Any idea why CHT drops that much and how to proceed with the high GAMI spread, are welcome.
In the mean time, we switched from magnetos to 2x PMAG, but this did not changed the situation, just easyer starting and better performance.
Best regards and thanks!
Dominik and Roland
My buddy has a RV-7A with an Aerosport IO-320, turning an Sensenich metal FP since about 200 hours. The fuel injection is a Silverhawk unit.
He told me a few times that something seams not as it should be. I looked at the data and do not get the cloue what it can be really.
I told him to make a GAMI spread, here the results:
The spread is in liters, here the equivalent in USG:
24.5L = 6.47 USG
22.0L = 5.81 USG
21.0L = 5.54 USG
After this, he cleaned the nozzle 1 and 3, but this did noch changed the situation.
I think we contact Don Rivera and get other nozzles.
One other thing, I found, when he is leaning, the cylinder 3 CHT drops by about 40 to 50?F, the others stay together more even. When he enrichen the mixture, cylinder 3 CHT comes back quickly!?
Picture when cyl 3 CHT drops (EGT top row, CHT bottom row):
And here when it comes back (cyl 3 is yellow here):
Does he run it too lean, so that cyl 3 is allready on the lean side of the peak? Here he has it at about 25L (6.6 USG) and past time 00:10 at 28L (7.3 USG).
Any idea why CHT drops that much and how to proceed with the high GAMI spread, are welcome.
In the mean time, we switched from magnetos to 2x PMAG, but this did not changed the situation, just easyer starting and better performance.
Best regards and thanks!
Dominik and Roland