Hey brain trust.
I have a 6a with an field overhauled Mooney C o-360 with 200hrs, CS MT, one slick timed at 23* and one Surefly with advance activated at 20*
When the motor was first built it had a ma-4-5-10-3878M. It was freshly overhauled. It always ran hotter then hell itself on takeoff.
Fuel flows in the mid 14s during the takeoff roll, slowly creeping up to 16 by 1000ft agl.
Doing a comparison on egt on takeoff vs cruise peak egt shows me taking off very close to peak EGT on 1&3 with only 2 really getting enough fuel to run cool.
Peak EGT vs climb EGT:
Time: 00:24:11-00:11:15
EGT1: 1440, -40.0
EGT2: 1435, -235.0
EGT3: 1365, -25.0
EGT4: 1435, -120.0
I purchased a 10-4164-1 from spruce and results were very rich. So rich it wouldn't runup on one mag full rich. 19gph+ on takeoff and required aggressively leaning by 3000ft or else.
If I rigged the mixture cable a 1/4" off the carbs full rich stop it became sort of usable. It's a real pain to manage. Now it's 18 GPH and holding steady at 17.5 GPH during climb with EGTs much closer together. Cylinders 1 and 3 were previously about 100° higher EGT during climb than now and CHTs are much easier to control. Still, if your not pulling the red knob above 3000ft even at at full throttle it will start to bog, very high workload to manage.
so a few questions:
In the short term: is rigging the mixture arm on the 4164 short of the full stop an ok and accepted practice for now so I can keep flying?
in the long term: are there a range of richer jets available for the 3878? The carb is stamped with "M" so should have the "Mooney mod" but still It looks like it will require at least another GPH to comfortably stay away from peak EGT and leave some cht margin for error on the climb.
I have included screenshots from the 3878m
Thanks!
I have a 6a with an field overhauled Mooney C o-360 with 200hrs, CS MT, one slick timed at 23* and one Surefly with advance activated at 20*
When the motor was first built it had a ma-4-5-10-3878M. It was freshly overhauled. It always ran hotter then hell itself on takeoff.
Fuel flows in the mid 14s during the takeoff roll, slowly creeping up to 16 by 1000ft agl.
Doing a comparison on egt on takeoff vs cruise peak egt shows me taking off very close to peak EGT on 1&3 with only 2 really getting enough fuel to run cool.
Peak EGT vs climb EGT:
Time: 00:24:11-00:11:15
EGT1: 1440, -40.0
EGT2: 1435, -235.0
EGT3: 1365, -25.0
EGT4: 1435, -120.0
I purchased a 10-4164-1 from spruce and results were very rich. So rich it wouldn't runup on one mag full rich. 19gph+ on takeoff and required aggressively leaning by 3000ft or else.
If I rigged the mixture cable a 1/4" off the carbs full rich stop it became sort of usable. It's a real pain to manage. Now it's 18 GPH and holding steady at 17.5 GPH during climb with EGTs much closer together. Cylinders 1 and 3 were previously about 100° higher EGT during climb than now and CHTs are much easier to control. Still, if your not pulling the red knob above 3000ft even at at full throttle it will start to bog, very high workload to manage.
so a few questions:
In the short term: is rigging the mixture arm on the 4164 short of the full stop an ok and accepted practice for now so I can keep flying?
in the long term: are there a range of richer jets available for the 3878? The carb is stamped with "M" so should have the "Mooney mod" but still It looks like it will require at least another GPH to comfortably stay away from peak EGT and leave some cht margin for error on the climb.
I have included screenshots from the 3878m
Thanks!
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