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Ref: Continued Engine Debate #1
Charlie was right that the oil control ring on the new Top Care Cyl's helps, but the rest of the story is that "RUST" is one of the greater detriments to the engines longivity, regardless of the manufacturer. TCM coated the pistons (moly) to overcome the scuffing inherent to early operation on the piston skirts, and is expected to wear off where contact is made with the cyl. wall. The Manganese Phosphate coating on the cylinder walls was applied to reduce rust formation on the walls for the first 25-50 hours only. There is no evidence of the coating after this. The hone pattern was revised to be a deeper, more agressive pattern, followed by second stage designed to smooth out the rough edges, all in the interest of retaining oil in the upper travel of the rings. The compression rings were given a staggered gap (more gap on the top ring) to reduce the tension of the top compression ring and distribute the load better between the two. At about the same time there was a change to the head design which was to help longivity. Back to RUST. After the Phosphate coating is worn away, the engine will develop a coating on the cyl. walls from combustion by-products, that are in themselves, slightly resistant to rust formation, but only for a short period of time. The engine needs to be FLOWN weekly to prevent rust formation from getting a tooth in the metal, and fly a minimum of 20 minutes after the engine temperatures have stabilized in order to burn off the hydro carbons (moisture and other contaminants). The worst thing you can do is to ground run the engine thinking that you are doing it a favor, the second worst thing is to pull the prop through weekly in an attempt to redistribute the oil. It doesn't work. RUST is an abrasive, once it is broken loose in the engine it acts like mini-sand particles and starts to accelerate the wear between parts, and if allowed to "pit" the cylinders can eventually cause a deterioration in compression (another long story). Thinking a little deeper into the engine, the rust is not limited to the cylinder walls, it attacks the cam and lifters as well, and this is the accelerator to cam and lifter wear, which increases cost at overhaul if they don't go flat before that. Aero Shell sells a oil to be used for short term storage of your engine, if you can't fly throught he winter, protect it.....
A major issue with builders has been to purchase the engine early to avoid the cost increses. This can bite you two ways, the first being the current warranty start time which does not start when you firstr run the engine, read it close. Second is the big sticker on the side of the box when yoiu receive it, it tells you when the engine runs out of preservitative life, and must be re-preserved. This is not a simple task when it's in the box, but must be done with the correct equipment to preserve yoiur $50K investment. Sitting on the hangar floor for a few years, spraying oil in the cylinders with improper equipment, isn't protecting a damn thing..... C,or L.....
If I'm not stoned for this one, I'll try to follow on with a discussion on extending the longivity of that TSIO....... It's all spelled out in the Top Care Health Check handbook. Mike DeHate
(Late)
LML website: http://www.olsusa.com/Users/Mkaye/maillist.html
Builders' Bookstore: http://www.buildersbooks.com/lancair
Please send your photos and drawings to marvkaye@olsusa.com.
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