cctsurf Posted November 19, 2020 Report Share Posted November 19, 2020 Just installed a surefly due to a magneto failure and the engine runs rough. Especially when I switch to it alone, it is very rough. Has anyone else experienced this? I have even heard a backfire (not on switching to the surefly, but in the middle of a run-up)! We replaced the wires (had to), and after the first test, replaced the spark plugs (a number tested high resistance). The roughness still is there. I followed Surefly's troubleshooting, the plug wires are correct, the timing is correct, the sim blinks the correct code. I have a number of jpi traces (not sure how to post that here) of run ups and a couple of flights around the patch, but I'm not good enough at reading them to tell what's going on. It really looks to me like cylinder 4 is the one having problems, and that it persisted through a plug change. Could be a bad plug wire? Do I contact surefly? Any other ideas? I should note that my IA doesn't have a lot of experience with the surefly, so I thought I would ask here. Thanks in advance! 1 Quote Link to comment Share on other sites More sharing options...
takair Posted November 19, 2020 Report Share Posted November 19, 2020 Have not heard of this. Surefly has pretty good support, give them a call. Sounds like you verified the timing by ensuring the blink sequence is correct? It is easy to mis-read. If it is one cylinder it is likely only one of three things....plug, lead or Surefly. Quote Link to comment Share on other sites More sharing options...
47U Posted November 19, 2020 Report Share Posted November 19, 2020 How does it run on the non-Surefly mag, by itself? Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 1 minute ago, takair said: Sounds like you verified the timing by ensuring the blink sequence is correct? Yes, I checked that. Long, short, long, long... Just now, 47U said: How does it run on the non-Surefly mag, by itself? BEAUTIFULLY. I'm beginning to wish I had just purchased a replacement magneto... Quote Link to comment Share on other sites More sharing options...
47U Posted November 19, 2020 Report Share Posted November 19, 2020 Hopefully, the Surefly replaced the right mag, so you won’t have to pull the battery box. Barring a complete review of the Surefly installation (which is sounds like you’ve done), certainly give Surefly a call to see what they have to say. There will be a solution, please report back your progress. Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 1 minute ago, 47U said: Hopefully, the Surefly replaced the right mag Nope, Left one (that's one of the reasons I jumped on the Surefly)... no more shower of sparks. =/ Quote Link to comment Share on other sites More sharing options...
47U Posted November 19, 2020 Report Share Posted November 19, 2020 Just now, cctsurf said: Nope, Left one (that's one of the reasons I jumped on the Surefly)... no more shower of sparks. =/ Same with me, left mag. Is possible the power wire has an intermittent connection? Try replacing the fuse, in case it’s got a bad solder joint on an end cap. It wouldn’t be the first time. (Grasping as straws, here.) 1 Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 Just now, 47U said: Is possible the power wire has an intermittent connection? Definitely worth a check. It would seem odd that it would repeatedly occur on the 4th cylinder, though. Quote Link to comment Share on other sites More sharing options...
philiplane Posted November 19, 2020 Report Share Posted November 19, 2020 (edited) It is possible, but unlikely, that the Surefly is the problem. It is most likely the spark plug or the ignition lead itself. In many cases, folding the ignition leads tightly and tie wrapping them can cause the center conductors to break, and pierce the outer braid. This causes a short to ground. Pull the harness off the Surefly and do a high voltage harness test to see if there is a cut, or a a broken conductor in the #4 lead. And if you have Champion plugs from 2014 or older, throw them away. Edited November 19, 2020 by philiplane 1 1 Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 Looking back to the first tests, I note that the trouble was not only on cyl 4, but also on cyl 1 or 3, but most recently, mainly on 4. I initially had newish (50 hrs) Tempest plugs on 1&3 and run out champion ones on 2&4. I replaced all of those with new Tempests before the 4th data set. The engine sounded the same bucking and even a backfire with the new tempests, same as with the old plugs. First test with new ignition system, notice the spike in egt3. Now it's on cyl #1... I was messing around with the mixture here because it ran better with the mixture leaned, but not good. Still old plugs. At ~2:45, I'm doing a mag check on the traditional magneto, at ~3-3:45, I'm doing a mag check on the Surefly. New plugs, doing a "magneto" test on the Surefly. Notice the drops on Cyl #4. same test as the above...except zoomed to the surefly "mag" test time. Quote Link to comment Share on other sites More sharing options...
kmyfm20s Posted November 19, 2020 Report Share Posted November 19, 2020 I would double check the external timing. That is setup differently than a traditional magneto. With mine you put #1 cylinder top dead center place SF and then double check the internal timing. Also double check the power line. It is best to go straight to the battery terminal. Any interruption in power supply reset the electronics in the SF and causes a rough engine. Quote Link to comment Share on other sites More sharing options...
Sabremech Posted November 19, 2020 Report Share Posted November 19, 2020 Just installed one on my C model not too long ago. Double check your wire harness for the correct position with the leads to the correct cylinder. The drawings in the installation manual of wire firing order are not bullet proof and a little confusing. You may have a lead swapped between cylinders. I called SureFly and asked them to make it clearer for the installers. David 2 Quote Link to comment Share on other sites More sharing options...
Bob - S50 Posted November 19, 2020 Report Share Posted November 19, 2020 I assume you checked the plug gaps? Quote Link to comment Share on other sites More sharing options...
Sabremech Posted November 19, 2020 Report Share Posted November 19, 2020 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. 1 Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 42 minutes ago, kmyfm20s said: Also double check the power line. It is best to go straight to the battery terminal. Any interruption in power supply reset the electronics in the SF and causes a rough engine. Just got off of the phone with Surefly. They said to check all of the electrical wires and grounds from the battery to the SIM. My issue does sound like the problems people have been having with the 24v systems, so I can see power supply as being the problem. 36 minutes ago, kmyfm20s said: I would double check the external timing. I have checked that repeatedly, it's timed to TDC. I'll check it again. 17 minutes ago, Sabremech said: Double check your wire harness for the correct position with the leads to the correct cylinder. The drawings in the installation manual of wire firing order are not bullet proof and a little confusing. You may have a lead swapped between cylinders. I agree that the drawings are a bit confusing. In fact I began to redirect the spark plug wires when I was rechecking all of my work before testing because I read them wrong. I looked at the diagrams a second time and realized that I had them right the first time. 5 minutes ago, Bob - S50 said: I assume you checked the plug gaps? New plugs gapped to .022. Original plugs were .018. Surefly said that was fine, the larger the better. So, it looks like I need to check some power wires... I'm guessing the battery to ground, I never did like it... Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted November 19, 2020 Report Share Posted November 19, 2020 Just now, 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. You guys know 1000x more about the A&P stuff than me, but my mechanic commented after putting in mine that my engine had an approved “alternate” installation of which harness wires went to which plug. So he had to do exactly what you said here... the standard harness I bought for the Surefly wasn’t going to have the correct lengths. Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 26 minutes ago, Ragsf15e said: You guys know 1000x more about the A&P stuff than me I'm working under supervision toward taking the A&P tests... This experience has increased my knowledge immensely, and I've logged about 30 hours working through it. More to come, it seems. 1 Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 Dumb question: I don't think the battery ground wire is connected to the correct place (it's connected to the back of one of the Lord mounts). Does anyone have a picture of the correct place for it? I've never been comfortable with the current position... but it has always worked. My IA says it might well be my problem...I agree. 1 Quote Link to comment Share on other sites More sharing options...
takair Posted November 19, 2020 Report Share Posted November 19, 2020 12 minutes ago, cctsurf said: Dumb question: I don't think the battery ground wire is connected to the correct place (it's connected to the back of one of the Lord mounts). Does anyone have a picture of the correct place for it? I've never been comfortable with the current position... but it has always worked. My IA says it might well be my problem...I agree. I don’t have a picture but that sounds very wrong. Do you have a picture? That could be your problem. Do you have any charging problems or noise in the headsets? Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 19, 2020 Author Report Share Posted November 19, 2020 Just now, takair said: I don’t have a picture but that sounds very wrong. Do you have a picture? That could be your problem. Do you have any charging problems or noise in the headsets? 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... Quote Link to comment Share on other sites More sharing options...
takair Posted November 20, 2020 Report Share Posted November 20, 2020 27 minutes 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... The potential problem I see is that the you get a stack up of parts not really intended to carry the current. They may or may not be bare metal. It also needs to get back to the airframe. Is there a jumper from the engine tot he airframe? Also, it could be a noisy ground which might affect the electronic ignition. It may not correct the issue, but it might..... 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 20, 2020 Report Share Posted November 20, 2020 The good news... very few lasting complaints have come from Sure Fly installs... it will get fixed... Got a picture of the ground going to the “rubber isolator”... The Lord biscuits are designed to isolate vibration... they may be isolating electricity as well... This sounds very wrong when it comes to grounding... Awesome double dipping opportunity... Working on your own Mooney, while earning credit towards your A&P... perfection! PP thoughts only, not a mechanic... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 20, 2020 Author Report Share Posted November 20, 2020 1 minute ago, takair said: Is there a jumper from the engine tot he airframe? There is a ground braid on the other side of the engine. 1 minute ago, takair said: They may or may not be bare metal. Also, it could be a noisy ground which might affect the electronic ignition. It may not correct the issue, but it might..... Agreed. I'm a big believer in good grounds. (= I just did engine mounts not that long ago, I can't say whether there was paint behind the nut and washer, but I'm pretty sure there isn't on the inside of the hole... It should be tight enough on that engine mount not to move around, but I would prefer to have it connected where it is supposed to be connected... I haven't figured that out. Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 20, 2020 Report Share Posted November 20, 2020 About Savvy graphs... You have done a great job of collecting data, and posting graphs... If you click share, and provide the link... there are people around here that run through the data really quick this way... Mags, and run ups tell a lot about how well the system is working... including timing of the mags... No need to complain about the choice to go with the Sure Fly... until the job is done... You probably made a great choice... getting the execution completed looks more challenging that it needed to be... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
cctsurf Posted November 20, 2020 Author Report Share Posted November 20, 2020 6 minutes ago, carusoam said: Awesome double dipping opportunity... Working on your own Mooney, while earning credit towards your A&P... perfection! I think my IA would prefer I be able to sign off my own work, anyway... Fewer Hangar Elves... This has been an immense project that started with a non-working magneto and has logged approximately 300 hours toward my A&P (I'd have to calculate it out)... I've written a parallel to "If you give a mouse a cookie" about it. "If you give a Mooney a p-lead" I'm at ~600 hours toward the 4700 I have to log. It seemed insurmountable 'till I started working on projects. I've got a Cherokee 140 that needs an engine overhaul, I really hope I can do a field overhaul under supervision, I think that would be great toward the P part of the A&P. 2 Quote Link to comment Share on other sites More sharing options...
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