Mixing Cylinders

How to keep the Cessna 170 flying and airworthy.

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lowNslow
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Mixing Cylinders

Post by lowNslow »

Anyone have any information on the pros and cons of mixing cylinders. I currently have new style Continentals on my engine, but can get the Superior's for about $300 less.
Karl
'53 170B N3158B SN:25400
ASW-20BL
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cessna170bdriver
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Post by cessna170bdriver »

Karl,

At one time in my current engine's prevous life, it had Superior cylinders (standard bore) on #'s 3 and 4, with old Continental cylinders (0.015 oversize) on #'s 1, 2, 5, and 6. It ran smooth this way for about 500 hours, until the current overhaul became necessary. I guess the first thing I'd be concerned about would be equal (or nearly so) piston weight on opposing cylinders.

Miles
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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lowNslow
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Post by lowNslow »

cessna170bdriver wrote:Karl,

At one time in my current engine's prevous life, it had Superior cylinders (standard bore) on #'s 3 and 4, with old Continental cylinders (0.015 oversize) on #'s 1, 2, 5, and 6. It ran smooth this way for about 500 hours, until the current overhaul became necessary. I guess the first thing I'd be concerned about would be equal (or nearly so) piston weight on opposing cylinders.

Miles
Miles, good point. They did balance the pistons when they rebuilt my engine so it would probably be a good idea to keep it that way. I am hoping I don't need to replace the cylinder, it is leaking a little air by the exhaust valve on one cylinder and I didn't have time to trouble shoot it. But just in case I have been shopping cylinders in case it needs replacing. Air Power,Inc. has the theO-300 cylinders for $599. http://www.factorycylinders.com/

By the way, they also have Autolite spark plugs for $9.98 if you buy 16 or more.
Karl
'53 170B N3158B SN:25400
ASW-20BL
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GAHorn
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Post by GAHorn »

If you pull that cylinder you can reface/regrind the valve, and/or replace the valve and seat, and return the cylinder to service using the same piston (if serviceable) with new rings. Otherwise, simply specify the new piston's weight parameters.
No problem mixing cyls from different mfr's.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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lowNslow
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Post by lowNslow »

Thanks George, I am hoping that's all it takes. Might just be a glob of lead deposit. My AI has a real nice boroscope and will be over next week to take a look.
Karl
'53 170B N3158B SN:25400
ASW-20BL
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