Lycoming fan. . .I am

[Robster]

Well, we just changed out one of our IO360-200's (A1B6) at TBO (2200 hrs.) for one of the new-designed roller-tappet engines. If these new designs are as good as the old, I'll be very happy. So far it's running great.

The old engine ran to TBO with just regular suggested maintenance intervals / oil changes. . .never had a cylinder off of it, and great compressions right to the end. Always used AeroShell 15w-50 year round.

If there's a bullet-proof aircraft engine, this is it!

CuJet. . .have you heard anything pro or con about the new engine design (roller tappets)? A Lycoming rep told me that they have very FEW parts in common with the older ones. . .new cases, crank, cam, bearings, cylinders etc.

 

[Cujet]

I don't currently have any of the roller equipped engines. However, from what I understand, they are quite the comprehensive improvement. The rollers should fully eliminate the camshaft "risk". Plus the roller ones are a touch smoother too. We recently removed a low time AEIO-540 engine with 200 hours TT. It was replaced with a Lycoming roller "rebuilt" straight from Lyc. (the 200HR engine went on a different aircraft)(the reason for the change was for sales/export requirements)

Anyway, for the few hours we ran it, the roller engine was smoother. Could not tell any difference in ultimate output, climb rate or other objective data. I would not expect anything significant, as the 200HR engine was healthy too.

The Cardinal RG guys love the roller IO-390 variant compared to the A1B6. Slightly more power, smoother, maybe faster speeds-better climb. No additional fuel consumption from what I hear. I'd love a 390 in my Cardinal. But the airframe "ain't" worth it. Maybe I'll spring for a Powerflow.

Did you install a 390?

 

[Robster]

Originally Posted By: Cujet


Did you install a 390?


I've never heard of the 390, but I'd love to bolt a couple of those onto our airplane! Is the 390 certified now?

As for operation, the new one starts quick and does have a nice smooth idle. . .I've got 27 hrs. on it as of today and I've added two quarts of oil (using AS 80, mineral)--not too shabby. . .

Thanks for your reply. . .

 

[Cujet]

Well, I believe the IO-390 and IO-580 are both fully certified and being installed in current production aircraft. Certainly the 580 is in the newer Extra 330's.

In the case of my Thunder Cardinal, the IO-390 is installed via a Lycoming STC. It's rated at 210HP, vs. 200HP. However, from what I understand, the 390 actually makes it's rated HP, the 360 does not. Hence the noticeable improvement in performance.

 

[Robster]

The new engine now has a little over 60 hrs. on it with no problems to report. It's now running the good 'ol AS 15w/50. I have noticed that the fuel flow is about 1.5 gph less at full throttle than the other one. . .I'm thinking the mechanics have to tweak the mixture control? I dunno, cause the EGT is normal when the fuel flows are adjusted to the same value in cruise. . .maybe the new design just burns less fuel per hour.

 

[Cujet]

That's weird. I've never seen a significant difference in fuel flow when the same power is being produced. Could it be indication error? How about at TO and Climb power?