O-300 Overhaul for '98C
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- cessna170bdriver
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Last edited by cessna170bdriver on Fri Aug 28, 2009 5:59 am, edited 1 time in total.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
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Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
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Last edited by cessna170bdriver on Fri Aug 28, 2009 6:00 am, edited 1 time in total.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- GAHorn
- Posts: 21303
- Joined: Fri Apr 12, 2002 8:45 pm
Roesbery, what you may be seing is cadmium plated line. I've seen that issued as fuel injector lines, but usually that also is tempered and has a silver-soldered bulb-fitting on the end. Tempered steel does not flare easily in small sizes without splitting.
'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.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- Roesbery
- Posts: 302
- Joined: Tue Apr 23, 2002 4:34 am
Did a flare one time, didn't split, but was a trick getting the tip of the flare tool started, been a few years (quite a few) still holding. Would like to change the copper line to the fuel pressure gauge to steel with a rust free outside. I don't trust copper in a high vibration flexing inviroment.
- GAHorn
- Posts: 21303
- Joined: Fri Apr 12, 2002 8:45 pm
That's the issue, of course. Copper will work harden and over time will also embrittle due to vibration. It's a poor item to use in pressure service. I'm frankly surprised that it hasn't had a mandatory service bulletin at the very least, and that's why I intend to replace mine when I can get a hose made.
Meanwhile...everyone might check their oil pressure fittings to see if they are ordinary AN fittings or if they are the correct restrictor fitting. The restrictor has a pin-hole in it to pressurize the oil sense line so that should the line break...you won't lose all you oil overboard in a flash....you'll just have a nasty oil leak to discover when next you land.
Here's a pic of one on a Lycoming:
http://www2.tech.purdue.edu/at/Courses/ ... itting.JPG
FWIW: The oil sense line should be filled with kerosene as a sense-oil. That way the gauge will be more responsive, especially in cold wx. Very lttle, if any, actual engine oil will enter the line. A larger capacity oil sense hose should alleviate that issue, as any pressurization of the hose should be less restrictive to congealed oil.
Meanwhile...everyone might check their oil pressure fittings to see if they are ordinary AN fittings or if they are the correct restrictor fitting. The restrictor has a pin-hole in it to pressurize the oil sense line so that should the line break...you won't lose all you oil overboard in a flash....you'll just have a nasty oil leak to discover when next you land.
Here's a pic of one on a Lycoming:
http://www2.tech.purdue.edu/at/Courses/ ... itting.JPG
FWIW: The oil sense line should be filled with kerosene as a sense-oil. That way the gauge will be more responsive, especially in cold wx. Very lttle, if any, actual engine oil will enter the line. A larger capacity oil sense hose should alleviate that issue, as any pressurization of the hose should be less restrictive to congealed oil.
'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.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
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Last edited by cessna170bdriver on Fri Aug 28, 2009 6:01 am, edited 2 times in total.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- N2255D
- Posts: 489
- Joined: Wed Apr 24, 2002 3:42 am
Personally I use MMO in the lineFWIW: The oil sense line should be filled with kerosene as a sense-oil. That way the gauge will be more responsive, especially in cold wx. Very lttle, if any, actual engine oil will enter the line. A larger capacity oil sense hose should alleviate that issue, as any pressurization of the hose should be less restrictive to congealed oil.
Walt Weaver
Spencer Airport (NC35)
Spencer Airport (NC35)
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
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Last edited by cessna170bdriver on Fri Aug 28, 2009 6:02 am, edited 1 time in total.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- GAHorn
- Posts: 21303
- Joined: Fri Apr 12, 2002 8:45 pm
I realize this was a jab ....N2255D wrote:Personally I use MMO in the lineFWIW: The oil sense line should be filled with kerosene as a sense-oil. That way the gauge will be more responsive, especially in cold wx. Very lttle, if any, actual engine oil will enter the line. A larger capacity oil sense hose should alleviate that issue, as any pressurization of the hose should be less restrictive to congealed oil.

'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.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
deleted by the author
Last edited by cessna170bdriver on Fri Aug 28, 2009 6:02 am, edited 1 time in total.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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