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The new rev D seems to behave differently than the previous one I had. We confirmed the dip switch settings and the led sequence of long-short-long-long at installation but EGT/CHT behavior seems to have reverted to the pre-Surefly pattern. The engine starts and runs fine, but it acts like it's not advancing beyond the 25 degrees. It's possible the timing map has simply changed. More testing needed

I finally was able to climb up to 9500ft and completed a lean SIM check on the Surefly at WOT ~65% power, FF 6.8 and it ran smooth and EGTs were stable. The Mag check was fine also but noticeably rougher than the Surefly. The only change made was that the 1 and 2 plugs were swapped for 3 and 4 per Surefly recommendations. I’m going to keep flying it and keep an eye out for any issues.

While researching my issues, I came across another Mooney pilot who was having similar issues that resolved with changing the Harness to New Horizons Maggie Harness. Any pireps?

Sandeep

Rich wrote: ↑Sun Oct 10, 2021 1:37 am The new rev D seems to behave differently than the previous one I had. We confirmed the dip switch settings and the led sequence of long-short-long-long at installation but EGT/CHT behavior seems to have reverted to the pre-Surefly pattern. The engine starts and runs fine, but it acts like it's not advancing beyond the 25 degrees. It's possible the timing map has simply changed. More testing needed

In the immortal words of Gild Radner's character Emily Litella, "Never Mind".

I was able to determine the behavior of the new one is the same as the original, as expected. Today it was
7500 ft
OAT 15 degC
2400 RPM
22.4"
9.8 GPH
EGTs ~1410
CHT 380's
145 KTAS

On maybe an unrelated note the plane had recently seemed to be a bit slower than normal, delivering only 141-142 KTAS at this altitude and power setting. Before this flight I took a spray bottle and debugged the leading edges and windscreen and wiped off accumulated dust on the upper surfaces. So it's back to normal cruise speed, either due to this action or wrinkles in the fabric of the universe.

Today a test to determine max EGT:
7000 ft.
OAT -2C
2400 RPM
WOT
Leaned normally to 1410 F EGT, CHT was ~354, ~10 GPH, 143-144 KTAS
Slowly leaned until EGT peaked and started down again.

Peak EGT turned out to be about 1500. CHTs stayed stable around 355 +/- 5, The +/- was reading fluctuation. There was no discernible correlation between EGT change and CHT. This is consistent with what I've seen before with the SF, where CHT is more closely related to OAT than EGT in this range of high-cruise power. After peaking, as I continued leaning, I brought EGT down to about 1475, 8 GPH. At this point I had lost some speed - high 130's (I didn't take exact note of the actual speed). Engine stayed subjectively smooth throughout.

Diamond_Dan wrote: ↑Fri Feb 12, 2021 1:59 pm And I am not impressed with the SureFly so far. My cylinders run hotter now but seem to produce less power so I am running richer to keep them cool. MPG drop!

I fixed a static leak and I believe my IAS has gone up a bit which may have been the cause of the efficiency drop. It's a bit hard to tell precisely as my autopilot was out of commission for a period of time (fixed now) and its getting colder. I am convinced enough to say that there was no performance loss and possibly a gain but I have yet to try it up high.

My Surefly troubles saga continues, and my plane is grounded at this time. Engine stumbles on Surefly, and EGT3 drops like a Rock. The Sim is going back to Surefly for a bench test.

For those of you with good results could you please share which plugs you are using, Ignition Harness, where you draw power from (battery or solenoid), installed on which side, ground location, and if you have the advanced timing enabled/where you picked the manifold pressure from?

In my case: I have the UREM38S fine wires, new Champion m4004 ignition harness, power from the master Solenoid with fuse, installed on the left, grounded to engine (I believe) and manifold pressure from Cyl 3.

Sandeep

mysands wrote: ↑Tue Nov 16, 2021 3:21 pm My Surefly troubles saga continues, and my plane is grounded at this time. Engine stumbles on Surefly, and EGT3 drops like a Rock. The Sim is going back to Surefly for a bench test.

For those of you with good results could you please share which plugs you are using, Ignition Harness, where you draw power from (battery or solenoid), installed on which side, ground location, and if you have the advanced timing enabled/where you picked the manifold pressure from?

In my case: I have the UREM38S fine wires, new Champion m4004 ignition harness, power from the master Solenoid with fuse, installed on the left, grounded to engine (I believe) and manifold pressure from Cyl 3.

Sandeep

Tempest UREM38S with the standard gaps. All were measured for gap and resistance before installation. We just reused the original Slick harness, installed on the left side. It's wired directly (via fuse) to the battery. Diamond had not grounded the p-lead shield at the mag, which we did. The main ground for the unit is to the engine case as a side effect of being bolted to it. Advanced timing is used and the MAP is taken off the MAP hose that feeds the VM1000, using a brass T-connector, so it's reading #4 manifold pressure, the same as our flight instrument. Care taken routing the MAP feed to the SF so it isn't squeezed or otherwise stressed by engine movement and oil lines and such. Timing LED correctly shows long-short-long-long (_ . _ _) at power-up.

In poking around, as one does, I stumbled across the Service Instruction for Lycoming’s incorporation of electronic ignition. This is a family of custom versions of the SF built for various Lycoming engines. The executive summary is that it only allows fixed-timing ignition. The dip-switch settings are preset based on the part number one orders and the codes are different than the generic SF units. The MAP port is left open to atmosphere.

I've purchased a Surefly SIM4N and am clearing the way for the mechanic's install. I had a long conversation with Surefly technical support and got most of my questions answered. Most importantly, I have the REF F so ok there. However, one thing Surefly asks is whether the engine monitor has a magnetic sensor for the tach. Tech support wasn't sure about whether the VM1000 uses this method. If it does it will need to be converted. Can anyone who has done this let me know what the situation is? Thanks. Bernie

Bernie - yes, the VM1000 uses a Hall Effect sensor. If you are installing one SureFly, you can move the sensor to the other (Slick mag) side.