Q: In troubleshooting an intermittent RPM dependent engine roughness for a friend’s O-360, I came across this General Aviation News column of yours from 2008.
I own a 1979 Warrior II with an O-320-D3G and am also curious whether Service Instruction 1294 would apply to my engine.
Lycoming does not have this SI (or SB) in its technical document collection. Google has also been unsuccessful in locating a copy. Do you have access to this Service Instruction?
Domenick Venezia
Seattle
Continental Motors Group has extended its catalog of FAA approved parts for Lycoming and Titan engines.
Roller lifters and roller camshafts for engines such as the Lycoming IO-360 L2A are now available and in stock, company officials noted.
The parts are designed, certified and manufactured by Continental Motors.
Roller lifters and roller camshafts kits are available as of today and are in stock, officials note.
Lycoming has issued Mandatory Service Bulletin 632 that requires owners to check their engines for connecting rods that contain bushings that do not meet Lycoming Engine’s specifications within the next 10 hours of operation. [Read more…]
Q: Hello, Paul. I live in South Africa, Johannesburg. I love reading your articles on engines. You have wise words. Thank you.
I have an RV-6 built by myself and my brother-in-law. We fitted a Lycoming O-320-B2C that got overhauled after 560 hours by Alton Engineering. [Read more…]
Q: I’d be most grateful if you could advise whether it would be feasible to take a narrow-deck Lycoming 360-A1A and rebuild it as a wide deck 360-A1A, with a new crankcase and cylinders. What parts could be reused otherwise?
Mark Holmes
Q: I have a Lycoming O-320 engine that was overhauled by an IA who has overhauled lots of engines and, ever since, the oil temperature runs very high.
The oil gauge was checked for accuracy, and the oil cooler was sent out, cleaned and checked. I replaced the varitherm and the induction tubes have new couplings and clamps with no leaks.
The aircraft is on floats, so 91 octane auto fuel is used. It runs very well.
Someone has suggested that the rings maybe too tight?
Anything else we should check or just pull the top off and start by checking the ring gaps?
B.J. Riester
Auburn, New York
A: B.J., my first thought after reading your email was that you’re barking up the wrong tree.
If you had mentioned the cylinder head temperatures were running high, then I might have believed the end gap on the rings was a possible source of the trouble.
I can also say that if we were seeing a lean condition from a leaking intake coupling this would also show up with higher cylinder head temperatures rather than higher oil temperatures. This has happened in the past where the cylinders have been chromed and have a choke at the top of the barrel like the nitrided cylinders.Since Lycoming provided straight chrome barrels only during the years of offering chrome cylinders, it never provided plain steel rings for choked barrels.
If the person who overhauled the engines just happened to install Lycoming piston rings without checking the end gap during assembly, there would be a problem. The Lycoming piston rings were for straight chrome barrels only and would fit a choked chrome barrel, but there would be insufficient end gap clearance, which would result in high cylinder head temperatures during engine operation.
I’d be curious to learn if when you replaced the oil cooler by-pass valve you complied with Lycoming Service Instruction 1316A or its latest revision?
If you just replaced the oil cooler by-pass valve without refacing the corresponding seat, then the chances of having a complete 360° seating surface for the new oil cooler by-pass valve may be the issue. It would not be unusual for these mismatched surfaces to allow some of the hot engine oil to not be forced through the engine oil cooler. The result of this would be a higher than normal oil temperature.
With regard to the type of fuel being used, I don’t believe that would have any bearing on the high oil temperature.
The only other thing that comes to mind that you might check is the air flow path to the engine oil cooler. If it is exactly like it was prior to the engine being removed for overhaul, then I guess we can count that out.
I would mention that the maximum oil temperature for your engine is 245° F continuous. On a freshly overhauled engine, you may see higher operating temperatures when compared to the engine temperatures prior to overhaul.
Since you didn’t provide any oil or cylinder head temperatures, I’m just assuming they may be exceeding the maximum allowable temperatures. I’ve tried to provide my best guess as to where you should focus your troubleshooting area.
Van’s Aircraft customers now have the option to add an electronic ignition system on their Lycoming engines. [Read more…]
Q: Are there any practical, appropriate and compliant modifications that can be made to a 150-hp, narrow-deck O-320? For example, can the compression ratio be tweaked a bit, or are there aftermarket exhaust systems with less back pressure, or is there any porting/polishing possible to effect a tad more power to the propeller? [Read more…]
Q: I have a unknown four-cylinder Lycoming that only has these numbers on the case: 2299-24 and 61863 assem. Any help would be greatly appreciated.
Jerry [Read more…]
Q: This engine was displayed at this year’s Reno Air Races. There was no information posted at the display, nothing to indicate who owned it, identification/designation, what it was or its intended use. It looked like three P&W R-4360 engines put together. Have you ever seen this engine or might you have any information on it?
It has the appearance of being a real engine yet, none of us in our small group at DVT have been able to find any information on it.
Any thoughts, comments, or information on this engine would be appreciated.
Jim Little
