Slick Starter Module
Posted: Mon Jun 01, 2020 11:06 pm
Had an interesting issue occur this weekend. On Saturday I flew doen to KCVN from KEIK, about a 2h45m flight. I normally check my engine screen about once ever 20 minutes to look specifically at EGT and CHT. About 40 minutes out at 9000 ft I noticed that the EGTs were a little off from normally. Specifically cylinders 1 & 3 were showing higher than normal EGT from where they were set at the beginning of the flight. Typically my #3 cylinder runs the hottest EGT and therefore is used for leaning. As is normally the case I lean to a temperature of 1435 degrees F on this cylinder... very very consistent. The other 3 cylinders normally settle in with degrees of this temperature. This results in a cyclinder head temperature of about 360 degrees F across the board. My fuel burn at this point is 10.2 gal/hr at 140 true airspeed. MP at 9000 ft was 22.1""hg and rp,s were set at 2530. Again all totally normally. But when I checked the screen at about 2 hrs into the flight for at least the 4th time, the EGT on #1 and #3 were higher than normal up at about 1490 degrees F. Everything else was totally normal. I increased the mixture just a little and and brought the EGTs back to 1435. Again, no other issues. Landed and shutdown uneventfully. On Sunday morning, the plane wouldn't start no matter what I tried. Everything was normal except for the fact that there seemed to be no spark, nothing even close to wanting to turn over. Keep in mind that this airport is in the middle of nowhere, New Mexico. But I was successful in getting the local mechanic out in about 15 minutes to take a look. He did a little trouble shooting... checked the mag timing, pulled the plugs... fuel flow... everything was perfect. So now the question is what is going on with the left mag... the plane of course starts on the left mag. Wasn't much else he could do at the moment, and he wasn't totally familiar with the Slick Start system. So we decided to tow the plane to the maintenance hangar and await the chieff mechanic's return from a flight. In the meantime I did a little research on the starting circuit and that started to point me to the Slick Start module... but it didn't seem to explain the EGTs during the flight because the Slick Start is technically disengaged once the plane has started. This morning a more formal test of the Slick Start based on the maintenance manual proved that to be the failure mode. So the part was ordered and hopefully it arrives Tuesday afternoon. Its literally a 5 minute install. I caught a new commuter flight back to Denver (only one on the Dornier Jet) and will head back down later in the week to fly 4ES back home.
I found a link on the PilotsofAmerica.com site that had a post of the exact issue in an RV. Same symptoms, but unfortunately he spent $1000 for a new mag that was not needed. After he found no change with the new mag, he tried disconnecting the Slick Start and his EGTs came back to normal. So I think we figured this out. But what I haven't figured out yet is why the Slick Start failure caused the EGTs to vary on #1 and #3 cylinders while in normal cruise. I'm also not sure why the RV was ableto be started with a bad Slick Start module. In the case of the DA40, the left mag does not have an impulse coupling normally found on planes without a Slick Start module. So perhaps the RV has a different setup depending on what engine he used.
Has anybody run into this issue? Does anybody have an explanation before I call Champion Tech support?
I found a link on the PilotsofAmerica.com site that had a post of the exact issue in an RV. Same symptoms, but unfortunately he spent $1000 for a new mag that was not needed. After he found no change with the new mag, he tried disconnecting the Slick Start and his EGTs came back to normal. So I think we figured this out. But what I haven't figured out yet is why the Slick Start failure caused the EGTs to vary on #1 and #3 cylinders while in normal cruise. I'm also not sure why the RV was ableto be started with a bad Slick Start module. In the case of the DA40, the left mag does not have an impulse coupling normally found on planes without a Slick Start module. So perhaps the RV has a different setup depending on what engine he used.
Has anybody run into this issue? Does anybody have an explanation before I call Champion Tech support?