Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
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iFlyNothing
Well, as any of you who've been following the Belize trip know, the 310 is back in operation. At 2100 hours SFRM, the last set of engines were tired and needed to be replaced. Driving factors included that the left engine was puking a profuse amount of oil out of the breather, and when and propping it felt like you were spinning the prop on a PT-6 (anyone who's done this will understand what I mean). Since the plane was donated to Cloud Nine with the engines at TBO, the fact that we got 2 years and 400 hours out of the plane is quite impressive. I attribute this to good care by the previous owner, and careful operation and good care by us plus use of the JPI. We were seeing 175 KTAS normally, and about 168-170 KTAS on a hot day with a plane full of dogs, both with 25-26 GPH combined fuel burn, running LOP with stock injectors.
Our goal was to get a good set of engines that would last us at least 2100 hours again (preferably longer), and hopefully do what we could to improve performance. With the trips that we do for Cloud Nine, even being able to shave 30 minutes off of an 8 hour day would be nice, provided we can do so economically. Running ROP is a bad option with this plane, because to keep CHTs low you have to run a ridiculous fuel burn. Because the engines were previously factory remans with new cases and cranks, we chose to have these engines overhauled by a reputable shop rather than do another factory reman or an upgrade STC (at this point, the only upgrade we could do would be a 300 HP IO-550 conversion vs. our current 300 HP IO-520s).
After talking to a number of overhaul shops, we chose to go with Charlie Merlot and Zephyr Aircraft Engines. Charlie has a great reputation for the quality of his work, both on this forum and outside. In a time when many well-known shops are having various quality control concerns, I haven't heard a single bad word uttered or typed about Zephyr. That gives us a great deal of confidence in their work. Additionally, Charlie was responsive and great to work with, and open to making these overhauls "custom" to our liking. He was also kind enough to provide Cloud Nine with a discount on the overhauls, which we do truly appreciate.
Beyond the standard overhaul procedure, we asked Charlie to have the rotating assemblies balanced and perform a 3-angle valve job on the cylinders. Vibrations are not only annoying in the cockpit and add to human fatigue, but they aren't good for any mechanical device. Anything you can do to reduce vibrations means more power is going into making the plane go, and less wear is being placed on the airplane. When asked what he would recommend on the cylinders to get some extra flow out of them, Charlie recommended the 3-angle valve job for a very reasonable price, so we went with that.
We also installed GAMIjectors in our engines, which GAMI provided us at the dealer cost (thanks, GAMI!). You all may remember the SkyTec ad in EAA - they were kind enough to donate us a pair of C24ST5 starters for that, which are more powerful and spin the engines faster. The Tanis heaters were working great, but the pads that get glued to the crankcase and sump were damaged during removal, and Tanis was kind enough to donate those to us, as well.
We decided to go with ECi Titan cylinders for the overhaul. This was a bit of a question mark for us, and time will tell if it was the right decision (or if there was a right decision). Most people I've talked to agree that ECi Titans are the best cylinders available for Continentals, despite their cracking issues. They also have supposedly improved their design vs. previous to make the cylinders better/stronger/etc. We'll see how that goes. So far, I've been very happy - but 25 hours doesn't tell you much!
While the plane was down, it came due for annual, so we did that as well. Also did a few other minor improvements on the aircraft - Jerry Temple gave us a set of his colored switch covers (which do a great deal for switch recognition, especially at night), and Whelen gave us a significant discount on a set of their landing and taxi lights.
On the airframe side, we replaced the exhausts, fuel hoses, and redid the cooling baffles. All are important items, and I think good to pay attention to at overhaul. Many people ignore them and end up with cracked exhausts, leaky fuel hoses, and poor engine cooling. It's worth noting that, if bad enough, poor cooling baffles will not only screw up your engines, but also screw up your cruise speed through increased drag. I also swapped the backup AI with the one in the Aztec. The Aztec had a newer 52D67 AI that drove the autopilot (same one the 310 uses). Newer, better condition, and also blue over brown instead of blue over black. Now all the AIs in the 310 match, and it helps update the interior. Lastly, I did some fiberglass work on the nose bowls and repainted them, which just improves appearance.
A few weeks ago, I took the 310 on its first test flights, and then shortly after Christmas flew to Belize and back. We now have 25 hours on the engines, and I can safely say I've flown it throughout most of the full operating envelope that I expect to so far as temperatures are concerned. What do I think?
FAST! Charlie and his team build one hell of an engine (or in this case would it be two hells of engines?). The first thing I notice on takeoff is that, while the engines would hit 2700 RPM before and then climb up to the takeoff max of 2850 RPM, now they go straight to 2850 RPM and off we go. Climb is significantly improved, and in cruise we're now seeing 180-190 KTAS on ~28 GPH combined. Part of this is that we are now running at 2500 RPM vs. 2300 RPM before, but to see a 10-15 kt improvement for only 3 gallons per hour, well, these are some happy engines. Even hot and heavily loaded we were seeing about 178 KTAS. Not bad, not bad at all. I've been keeping altitudes low for break-in. Oil consumption is very good, and at 25 hours the oil still looks brand new. These engines are solid. Best of all, no leaks!
We're still sorting out a few minor things with the plane, which is not unexpected. The engines are solid and happy, though.
Really, the whole plane feels surprisingly newer from the changes made. Not only is it faster and more efficient, but taking care of the wear on the nose bowls makes it look sharper sitting on the ramp. The interior feels newer with new switch covers vs. the old, worn, faded and discolored switch covers, and lastly having the blue over brown AIs on both the pilot and co-pilot side. The only part of the panel now that feels old is the Collins Nav/Com (which is on its way out and we will likely replace before long).
The LED landing and taxi lights have made a believer out of me for the positives of LED in aircraft applications. Not only do they have a significantly lower current draw, but I can see where I'm going much better for night taxiing and takeoffs, and it does help update the look and feel of the plane. Perhaps the biggest improvement is the taxi light. With standard incandescent taxi lights, you get a very dim glow that is effectively useless, at least on the planes I've flown. For the Whelen lights, my understanding is the taxi light is identical to the landing lights, other than having a 40 degree diffuser instead of a 10 degree diffuser. This means you get as much light as a landing light, just spread out over a wider area. It's a great improvement.
To anyone getting ready to consider an engine overhaul, I can certainly recommend Charlie and Zephyr, and would suggest that you talk to them in weighing your options.
Now we're 1% of the way towards our next set of engines. Let's see how this goes...
Our goal was to get a good set of engines that would last us at least 2100 hours again (preferably longer), and hopefully do what we could to improve performance. With the trips that we do for Cloud Nine, even being able to shave 30 minutes off of an 8 hour day would be nice, provided we can do so economically. Running ROP is a bad option with this plane, because to keep CHTs low you have to run a ridiculous fuel burn. Because the engines were previously factory remans with new cases and cranks, we chose to have these engines overhauled by a reputable shop rather than do another factory reman or an upgrade STC (at this point, the only upgrade we could do would be a 300 HP IO-550 conversion vs. our current 300 HP IO-520s).
After talking to a number of overhaul shops, we chose to go with Charlie Merlot and Zephyr Aircraft Engines. Charlie has a great reputation for the quality of his work, both on this forum and outside. In a time when many well-known shops are having various quality control concerns, I haven't heard a single bad word uttered or typed about Zephyr. That gives us a great deal of confidence in their work. Additionally, Charlie was responsive and great to work with, and open to making these overhauls "custom" to our liking. He was also kind enough to provide Cloud Nine with a discount on the overhauls, which we do truly appreciate.
Beyond the standard overhaul procedure, we asked Charlie to have the rotating assemblies balanced and perform a 3-angle valve job on the cylinders. Vibrations are not only annoying in the cockpit and add to human fatigue, but they aren't good for any mechanical device. Anything you can do to reduce vibrations means more power is going into making the plane go, and less wear is being placed on the airplane. When asked what he would recommend on the cylinders to get some extra flow out of them, Charlie recommended the 3-angle valve job for a very reasonable price, so we went with that.
We also installed GAMIjectors in our engines, which GAMI provided us at the dealer cost (thanks, GAMI!). You all may remember the SkyTec ad in EAA - they were kind enough to donate us a pair of C24ST5 starters for that, which are more powerful and spin the engines faster. The Tanis heaters were working great, but the pads that get glued to the crankcase and sump were damaged during removal, and Tanis was kind enough to donate those to us, as well.
We decided to go with ECi Titan cylinders for the overhaul. This was a bit of a question mark for us, and time will tell if it was the right decision (or if there was a right decision). Most people I've talked to agree that ECi Titans are the best cylinders available for Continentals, despite their cracking issues. They also have supposedly improved their design vs. previous to make the cylinders better/stronger/etc. We'll see how that goes. So far, I've been very happy - but 25 hours doesn't tell you much!
While the plane was down, it came due for annual, so we did that as well. Also did a few other minor improvements on the aircraft - Jerry Temple gave us a set of his colored switch covers (which do a great deal for switch recognition, especially at night), and Whelen gave us a significant discount on a set of their landing and taxi lights.
On the airframe side, we replaced the exhausts, fuel hoses, and redid the cooling baffles. All are important items, and I think good to pay attention to at overhaul. Many people ignore them and end up with cracked exhausts, leaky fuel hoses, and poor engine cooling. It's worth noting that, if bad enough, poor cooling baffles will not only screw up your engines, but also screw up your cruise speed through increased drag. I also swapped the backup AI with the one in the Aztec. The Aztec had a newer 52D67 AI that drove the autopilot (same one the 310 uses). Newer, better condition, and also blue over brown instead of blue over black. Now all the AIs in the 310 match, and it helps update the interior. Lastly, I did some fiberglass work on the nose bowls and repainted them, which just improves appearance.
A few weeks ago, I took the 310 on its first test flights, and then shortly after Christmas flew to Belize and back. We now have 25 hours on the engines, and I can safely say I've flown it throughout most of the full operating envelope that I expect to so far as temperatures are concerned. What do I think?
FAST! Charlie and his team build one hell of an engine (or in this case would it be two hells of engines?). The first thing I notice on takeoff is that, while the engines would hit 2700 RPM before and then climb up to the takeoff max of 2850 RPM, now they go straight to 2850 RPM and off we go. Climb is significantly improved, and in cruise we're now seeing 180-190 KTAS on ~28 GPH combined. Part of this is that we are now running at 2500 RPM vs. 2300 RPM before, but to see a 10-15 kt improvement for only 3 gallons per hour, well, these are some happy engines. Even hot and heavily loaded we were seeing about 178 KTAS. Not bad, not bad at all. I've been keeping altitudes low for break-in. Oil consumption is very good, and at 25 hours the oil still looks brand new. These engines are solid. Best of all, no leaks!
We're still sorting out a few minor things with the plane, which is not unexpected. The engines are solid and happy, though.
Really, the whole plane feels surprisingly newer from the changes made. Not only is it faster and more efficient, but taking care of the wear on the nose bowls makes it look sharper sitting on the ramp. The interior feels newer with new switch covers vs. the old, worn, faded and discolored switch covers, and lastly having the blue over brown AIs on both the pilot and co-pilot side. The only part of the panel now that feels old is the Collins Nav/Com (which is on its way out and we will likely replace before long).
The LED landing and taxi lights have made a believer out of me for the positives of LED in aircraft applications. Not only do they have a significantly lower current draw, but I can see where I'm going much better for night taxiing and takeoffs, and it does help update the look and feel of the plane. Perhaps the biggest improvement is the taxi light. With standard incandescent taxi lights, you get a very dim glow that is effectively useless, at least on the planes I've flown. For the Whelen lights, my understanding is the taxi light is identical to the landing lights, other than having a 40 degree diffuser instead of a 10 degree diffuser. This means you get as much light as a landing light, just spread out over a wider area. It's a great improvement.
To anyone getting ready to consider an engine overhaul, I can certainly recommend Charlie and Zephyr, and would suggest that you talk to them in weighing your options.
Now we're 1% of the way towards our next set of engines. Let's see how this goes...
thing is they don't really indicate the quality of flow. I remember taking a pair of SBC 'Turbo' heads and opening from 2.02s to 2.05s and lost .2 seconds. Another buddy handed me a set of Vortecs and I wouldn't touch them, they finally figured them out, then gave up the whole engine lol.
