Surefly Runs Rough

[cctsurf]

If anyone wants to look at my Savvy graphs, here's the link:  https://apps.savvyaviation.com/my-flights/4727/3b752d02-75cc-4be3-92da-36282c7276ce

18 minutes ago, carusoam said:

f you click share, and provide the link...  there are people around here that run through the data really quick this way...

THANKS!

[cctsurf]

Found one picture of the ground...  Can that REALLY be?  Still looking for other pictures.

[carusoam]

I marked up one of the graphs...

Unfortunately I have no idea where I saved the image...   

It saved the images in two different places, original and marked up....

The blue circle, and arrows point out where fuel isn’t burning very well...

The green range... all four cylinders seam to be working well together... 

Best regards,

-a-

[Sabremech]

Here’s a picture of my ground wire. I believe it hooks to the oil sump flange. 

[cctsurf]

Just now, Sabremech said:

I believe it hooks to the oil sump flange

I like that idea better than what I just posted.

Here are some other pictures that I found on MS:

Similar to the one above:

Not sure where this one goes:

[carusoam]

David’s engine, horizontally mounted...

-a-

[carusoam]

CC,

Check your EGTs...

There are some times during the operation, the fuel isn’t getting burned for some reason... most likely not a mag issue... when one mag is off, the EGTs rise a little...

Yet other times... all seems to be good...

I marked up one of your graphs and posted above where I see what is happening...

If you have a good, slow,  run-up... 15 seconds on each mag... we can see a bit more of what is going on with the mags separated out...

Best regards,

-a-

[PT20J]

Assuming (likely) that the SIM itself is not malfunctioning, and is installed and timed properly, there are three possibilities:

1) If the SIM has a bad power or ground connection (be sure to check the fuse holder) that causes power to fluctuate, it can shut down and reboot. This will cause it to affect all cylinders simultaneously. 

2) If there are voltage spikes on the power line greater than 40 or so volts, it will cause the SIM to shut down and reboot. This has only been seen on some 28 volt systems. Again, it will affect all cylinders simultaneously.

2) If there is a problem with an ignition harness or spark plug it can affect one cylinder. Since you have replaced and gapped the plugs that would tend to rule out the plugs. I might test the harness especially since it is new and untried.

Skip

[takair]

If you have a large braid to the engine than having the ground going to the footwell is not terrible.  I’ve never seen that routing for oil cooler lines.  Does that go above the cylinders?

[philiplane]

A large (#2 or #0) ground wire, or braided strap, should connect the airframe/battery to the engine. Lycomings have 1/4" and 5/16" bolt holes in the back of the engine at the accessory case specifically for ground straps. 

[cctsurf]

1 hour ago, carusoam said:

There are some times during the operation, the fuel isn’t getting burned for some reason... most likely not a mag issue... when one mag is off, the EGTs rise a little...

If you look at the blue circle, notice that the rpm dropped, I'm doing a mag check at that point, and that is what happens when I do.  This one fell on egt1.  Notice that most of the egts rose.

The green circled region is very low rpm, I'm not absolutely sure what's going on in the egts.

All of the times you look at my logs right now, I'm doing lots of mag checks, they look very similar to the blue circled area.  Some have egt rises and are very consistent, those are on the magneto, when I go to the sim, I get roughness and that's what this thread is all about.

 

48 minutes ago, PT20J said:

If the SIM has a bad power or ground connection (be sure to check the fuse holder) that causes power to fluctuate, it can shut down and reboot. This will cause it to affect all cylinders simultaneously. 

That makes me concerned, the technical support said that inconsistent power can also make engines run rough.  I hope he's right.  That's the assumption I'm working under right now.

My IA was fairly sure it wouldn't be problems with the new ignition harness, but it definitely bears testing as I move forward.  Mike Busch likes to talk about infant mortality.  Despite what I said earlier, the problem moves around, though, so I'm not certain it is one particular ignition lead.

 

46 minutes ago, takair said:

I’ve never seen that routing for oil cooler lines.  Does that go above the cylinders?

That's how many of the early c's, d's, and even e's were routed, over the cylinders, through the doghouse.  I have the original holes patched in my '62.  It baked oil hoses and in Mooney sbm20-110, they called for a reroute.  Seeing as that was not an AD, it has not been done on all early mooneys.

41 minutes ago, philiplane said:

A large (#2 or #0) ground wire, or braided strap, should connect the airframe/battery to the engine. Lycomings have 1/4" and 5/16" bolt holes in the back of the engine at the accessory case specifically for ground straps. 

I have a pretty good braid, however, I tend to be fairly over-concerned about grounds.  I will probably run a new wire to one of those bolt holes.  I recently used one to ground my engine monitor.

[cctsurf]

The Green circle is a mag check on the magneto, the blue circle is a mag check on the SIM.  All over the place.

[carusoam]

Great explanation of the extra details, CCT...

They are required, to get the most out of the experimentation you have done...

On the Sure Fly, EGT1 clearly goes on a bit of hiatus... RPM is going to drop as a side affect...

During the low rpm portion... the ODD side looks like it is being affected...

There isn’t much in the ignition system that affects one side more than the other... accept the possibility of type of plugs being used...

The bottom of one side is typically run by one mag, the other side is run by the other mag...

With the SF... some people have chosen to run all of the bottom plugs on the SF....

Did you connect all the bottom plugs to the SF?

Properly wired... still wouldn’t have the EGTs going all over like this....

 

Double check all the ignition wires... you might have two (?)... causing  a bit of a stir...

If they get swapped at the mag... it is really easy to do... 

Mixing them up at the plug end, is a bit harder... because of length challenges...

PP thoughts only, not a mechanic...

Best regards,

-a-

 

[cctsurf]

I'm a little confused about you talking about EGT1 taking a hiatus, the purple line, EGT4 takes the longest to rise, but all of them peak really badly.  I thought EGT4 and EGT1 were the issue, but I'm willing to be corrected.  Can you help me understand what you are seeing?

6 minutes ago, carusoam said:

Did you connect all the bottom plugs to the SF?

I went with the normal layout, surefly 1&3 are on the bottom and 2&4 are on the top.  I've considered moving things around, but right now I'd settle for a smooth running engine.

I've checked numerous times whether I got the wires switched, but it would be the easiest to correct...  I'll look better at the ignition wiring diagram and check it out.

Thanks!

[carusoam]

Hmmmm...

The graph with the two blue, and two green circles...

First blue circle, Where the red EGT1 line drops low, while the other three go a little high...

First green circle, where both the red EGT1 and its partner the brown EGT3 drift lower...

Sorry for the confusion... the delay between posts is adding a bit of challenge...   

Its a lot of memory being used... a great exercise...

Best regards,

-a-

[cctsurf]

15 minutes ago, carusoam said:

Sorry for the confusion... the delay between posts is getting a bit challenging...   

Sorry, had to go have dinner with the family.

Thanks, ok, I was looking at the graph I posted later and was confused.

I'm having difficulty finding a definitive plug wire output diagram for slick magnetos, I had to assemble it from the --less-than-helpful-- diagrams supplied by Surefly.  Lycomings fire 1-3-2-4, and Surefly supplies the picture below (without the blue).  Am I correct in numbering the leads as I have?  The magneto I replaced was a s4ln-200, which is left rotation.

[carusoam]

Let’s see if we can have David look over your shoulder...

@Sabremech just mentioned how difficult it was for him to understand the wiring diagram... he called SF to let them know what he was seeing...

Find his posts below (I copied it and put it there)... or further up the thread and give them a good look over... see if something stands out there...

I’ll do the same... but only as a PP... 

 

What is the standard for describing our engine’s rotation?

From behind?   The prop is turning clockwise... is that left or right(?) (my usefulness is dwindling...)

Best regards,

-a-

[carusoam]

5 hours ago, Sabremech said:

I think what caused me issues is that #1 cylinder on the Bendix mag is not in the same location as #1 on the SureFly. I ended up having to swap half of each mag harness wires to get the proper length of harness to each cylinder and the proper firing order. 

This is the post from David that I was referring to...

Could be what you might be seeing... (?)

-a-

[bmcconnaha]

My IA replaced an ignition harness on a cirrus i used to own.  ran fine on both mags.  ran fine on one mag.  ran terrible on the other.  he had mixed a plug lead up between cylinders.  he normally is very careful, but things can and do get mixed.  If the timing and ground is fine, id confirm correct locations for each lead.  

[cctsurf]

I Looked at Sabremech's posts, and that's what I noted, the #1 cylinder on the Bendix mag is not in the same location as #1 on the SureFly.  My wires weren't bad for length...

I don't know what the standard for our engine's rotation, but I'm pretty sure the magneto rotated the same as the SIM now rotates, so if it rotated left, which I can find (https://www.qaa.com/products/aircraft-magnetos/bendix-magnetos/bendix-magneto-s4ln-200) and the surefly materials describe the "ln" part as being left turning, I'm fairly sure that it lays out the way I have diagrammed it (below)

4      2

1       3

But I'm always open to being wrong on that...  It would be WAY easier than many of the other options I have considered.

[carusoam]

Let’s see if @M20Doc is in the neighborhood...

I think he has seen a few Sure Flight installations by now...

Best regards,

-a-

[47U]

5 hours ago, cctsurf said:

6 hours ago, philiplane said:

A large (#2 or #0) ground wire, or braided strap, should connect the airframe/battery to the engine. Lycomings have 1/4" and 5/16" bolt holes in the back of the engine at the accessory case specifically for ground straps. 

I have a pretty good braid, however, I tend to be fairly over-concerned about grounds.  I will probably run a new wire to one of those bolt holes.  I recently used one to ground my engine monitor.

My battery negative terminal is grounded to the engine case under the left mag.  There’s a braided strap from the lower right engine mount to the firewall at the copilot’s footwell.

 

[Guest]

12 hours ago, cctsurf said:

I don't have a picture, it was obviously an attempt at getting a better ground...  Thinking about it, the bolt does go straight through the engine at the top back, so it should be fairly good connection to the engine.  I was initially thinking about the isolation that occurs in the engine mount itself, but that's not where the connection would be.  I have never had any charging problems or noises in headsets...

I question whether the bolt will retain correct torque.  The cable terminal is copper and fairly soft.

Clarence

[Guest]

8 hours ago, carusoam said:

Let’s see if @M20Doc is in the neighborhood...

I think he has seen a few Sure Flight installations by now...

Best regards,

-a-

I’ve installed one on an RV4, which has since moved away, and another on an RV10.  The RV10 over took it off and sent it back, he was never happy with how it worked.  None of the certified airplanes I look after have one installed.

Clarence

[Sabremech]

I’ll stop out at my hangar today and confirm the wire harness routing. Along with the Surefly, I installed a new Slick harness that had the cylinders marked on them to where they were routed. It definitely was not straight forward to me as the first time installing one, but it works beautifully with fast starts and extremely low mag drop on the left side. 
David