Piper Saratoga Turbo Lycoming TIO-540-SIAD excessive fuel burn

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Joe Vedda

Filing Flight Plan
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Joe Vedda
Hi, I own a 1980 Saratoga Turbo that burns 21 GPH at 65% power book says 16. Have had my local mechanic look at everything and they cant find a reason why. Anyone know a great mechanic that specializes in this motor that can help me out. Im in Ohio
Thanks in advance !!
 
@Joe Vedda, The Lycoming publications (which I don't have anymore) recommends EGT operating temperatures to be about 50 degrees rich of peak. Get the aircraft settled in to cruise then lean until peak and slightly enrich it. If you have 6 point EGT lean to the hottest cylinder then about 25*f rich of peak.

The last TIO-540-S1AD I flew the avionics guys put the redline on the digital EGT around 1450*F. It should be closer to 1650*F. Once the aircraft was operating with the actual peak EGT the fuel flow was right on the chart values in the Flight Manual.

Don't know enough about your situation but, the publications for the 100 or so Turbo Saratoga ever built are very rare. Most of the instrument and avionics shops use the non-Turbo publications during setup.
 
Klaus the Piper power tables are notoriously badly compensated for that install (and for Turbo Arrow, but madly, close for the SIO) 360-B!B in the Seneca. At what are TAS, you cruising?

(and that install runs HOT)

B
 
I flew 35hrs in a TIO-540 over the last few days and found chts almost always below 330 - except in cruise.
When I leaned it below 18gph (book said 16) in cruise (2400 & 26")* the CHTs went to 390. I know Lycoming says 390 is fine but I'm not liking it. TIT was 1600 and I think most will agree that doesn't maximize cylinder or turbo life.
Open to suggestions.
*almost always 20 over ISA these days; global warming I guess.
 
Joe Vedda said:
Hi, I own a 1980 Saratoga Turbo that burns 21 GPH at 65% power book says 16. Have had my local mechanic look at everything and they cant find a reason why. Anyone know a great mechanic that specializes in this motor that can help me out. Im in Ohio
Thanks in advance !!
Click to expand...
The service manual says if you have high fuel flow indicated on the gauge, you have one or more plugged fuel injector nozzles.
 
Pinecone said:
Do you know how to properly lean it??????
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I was taught by my instructor to lean TIT to 1550. the CHT never get hotter than 375. I don't mind using more fuel to be gentle on the engine. but 5 GPH seems excessive.
 
Clip4 said:
The service manual says if you have high fuel flow indicated on the gauge, you have one or more plugged fuel injector nozzles.
Click to expand...
Thanks for the reply, I replaced all of them. New motor with 120 hours so far.
 
Let'sgoflying! said:
I flew 35hrs in a TIO-540 over the last few days and found chts almost always below 330 - except in cruise.
When I leaned it below 18gph (book said 16) in cruise (2400 & 26")* the CHTs went to 390. I know Lycoming says 390 is fine but I'm not liking it. TIT was 1600 and I think most will agree that doesn't maximize cylinder or turbo life.
Open to suggestions.
*almost always 20 over ISA these days; global warming I guess.
Click to expand...

Joe Vedda said:
Hi, I own a 1980 Saratoga Turbo that burns 21 GPH at 65% power book says 16. Have had my local mechanic look at everything and they cant find a reason why. Anyone know a great mechanic that specializes in this motor that can help me out. Im in Ohio
Thanks in advance !!
Click to expand...
Also it is summer here and 86-90 out. on take off I never achieve 100% power. usually only 94-96 percent. When I first started flying the plane I use to overboost and have to pull back a bit to maintain 100%. Is that typical of a hot day or do I need to have that adjusted ?
 
Is your fuel flow transducer known to be good / calibrated correctly?
 
Klaus M said:
@Joe Vedda, The Lycoming publications (which I don't have anymore) recommends EGT operating temperatures to be about 50 degrees rich of peak. Get the aircraft settled in to cruise then lean until peak and slightly enrich it. If you have 6 point EGT lean to the hottest cylinder then about 25*f rich of peak.

The last TIO-540-S1AD I flew the avionics guys put the redline on the digital EGT around 1450*F. It should be closer to 1650*F. Once the aircraft was operating with the actual peak EGT the fuel flow was right on the chart values in the Flight Manual.

Don't know enough about your situation but, the publications for the 100 or so Turbo Saratoga ever built are very rare. Most of the instrument and avionics shops use the non-Turbo publications during setup.
Click to expand...

That is great for Lycoming to be selling engines and parts. 50 ROP is in the heart of the danger zone. You want to be LOP or minimum 125 ROP. Unless you are at less than 65% power, then it doesn't matter.

EGT numbers have no use as numbers. Only in terms of relationship to peak. Alcor had it right with the first EGT gauges, no numbers. A slight change in location of the probe will change the indicated temp. In N/A engines, you can use the numbers to lean in the climb to about the same EGT as take off, but again, you could do this with a pointer.
 
Joe Vedda said:
I can only assume so. all new panel
Click to expand...

If this occurred right after panel upgrade, it is likely the K-factor was set wrong. I just got my plane back from a panel upgrade and the first takeoff the FF was 53 GPH, for a TSIO-360. NO WAY.

This one is very strange as it is the same fuel flow transducer that was dead nuts on with the previous JPI and K-factor of about 29,000. In the Garmin, setting the K-factor to 69,000 is still too low. My cruise, LOP, is normally 10. GPH. With the new setup, it reads 11.8, but the fuel used is the normal around 10.

We are going to replace the fuel transducer with a higher performance one.

To check yours, fill to a know amount (tabs or full). Reset the totalizer. Fly a fairly long flight. Compare the totalizer to the actual fuel pumped into the airplane to the same fuel level (tabs or fuel). That will tell you if your K-factor is off.
 
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