67 copper oil pressure line keeps snapping
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,019
Likes: 2
From: Russellville, Kentucky 1967 Sting Ray & 2001 C5
67 copper oil pressure line keeps snapping
I have a 67 small block and have had the copper oil pressure line (that leaves the rear of the block, and goes to the oil pressure gauge) snap on me twice now, right at the block fitting. Aside from the mess, I have been fortunate enough to notice the drop in oil pressure before I lost the engine. Does anyone have a fix or upgrade for this? Vibration appears to be the culprit. I've tried to loop the line and it didn't help. It has snapped twice now in 2 years. Help please!!!!
Last edited by RFJohnston; Aug 21, 2004 at 10:25 PM. Reason: wrong thread
Team Owner
Joined: Jul 1999
Posts: 26,545
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From: Huntersville NC
Originally Posted by paul67
The 1963-67 line was copper but that was changed to plastic 1968 through 1973. I suspect you are experiencing the reason for the change. I would modify to plastic.
My 68 has a curly copper line. Have not had any problems with it so far....
Safety Car
Joined: Nov 2003
Posts: 4,273
Likes: 1
From: Pittsford NY
Originally Posted by PRND21
your kidding!? My 68 has a curly copper line. Have not had any problems with it so far....
My 68 has a curly copper line. Have not had any problems with it so far....small loop or 2 before connecting to the engine might avoid
the stress that is causing it to break.
Team Owner
Joined: Jul 1999
Posts: 26,545
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From: Huntersville NC
Originally Posted by jerrymcb
Just a guess but I think there is a hint here. I wonder if a
small loop or 2 before connecting to the engine might avoid
the stress that is causing it to break.
small loop or 2 before connecting to the engine might avoid
the stress that is causing it to break.
Melting Slicks
Joined: May 2004
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From: Gulf of America
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I'm thinking the same thing as others. Maybe winding the copper tubing like a spring just off the block might help it take the stress better providing the replacement line has enough slack. My '72 has plastic tubing and it did crack right at the fitting on the block. I replaced the fitting at the block with a 45 degree compression fitting which gave it a less stressful, straighter shot at the firewall. You might try this as well. Funny thing is every time I go to the local dragstrip (NHRA), they ding me on the plastic tubing. They insist I change it to a metal tubing. So far, I've resisted. Charles
Le Mans Master
Joined: Mar 2004
Posts: 7,446
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From: Little Rock AR
(Using my best Cliff Clavin immitation) - This is a common misconception. 
The original lines were not copper but copper plated steel. They will be magnetic if you put a magnet up to them. The copper line will work harden due to vibration over time and crack as you have already found out. You need a steel or plastic line as a replacement.
-Mark.
The original lines were not copper but copper plated steel. They will be magnetic if you put a magnet up to them. The copper line will work harden due to vibration over time and crack as you have already found out. You need a steel or plastic line as a replacement.
-Mark.
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Team Owner
Joined: Jul 1999
Posts: 26,545
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From: Huntersville NC
wow! never thought there would be so much interesting stuff to learn about the oil guage line...
1. I will check mine with a magnet to see if it is copper or copper plated steel.
2. Mako72. Tech actually looks under your engine and checks your oil line?? They don't even raise my hood!
3. "original coil" eh? interesting. wonder if there is a pic in the AIM..
1. I will check mine with a magnet to see if it is copper or copper plated steel.
2. Mako72. Tech actually looks under your engine and checks your oil line?? They don't even raise my hood!
3. "original coil" eh? interesting. wonder if there is a pic in the AIM..
Melting Slicks
Joined: May 2001
Posts: 2,131
Likes: 4
From: May help you? You can sure as hell try!
When connecting the oil pressure line in my '68 I saw that the original setup called for a copper line running directly from the engine to the gauge inside. For fear of dealing with the same problem you are experiencing, I went with a '69 style oil line connection. This uses a copper line about 1' long that connects from the pressur tap hole from the engine near the oil filter, and leads up to a bracket that mounts to the back of the cylinder head. Attached to the bracket is a fitting that connects the copper line to a black plastic line. The black plastic line leads into the passenger compartment and connects to the the gauge. I debated about the "Factory correct" installation vs. making the upgrade, but the fear of hot engine oil spilling all over hot exhaust manifolds won out over "FCR".
The black plastic line will tolerate much more flexing as the engine moves and vibrates than will a copper line. Copper has a tendency to work harden as it flexes causing it to become brittle over time.
The '69 up oil line kit is available from Paragon.
The black plastic line will tolerate much more flexing as the engine moves and vibrates than will a copper line. Copper has a tendency to work harden as it flexes causing it to become brittle over time.
The '69 up oil line kit is available from Paragon.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
Originally Posted by PRND21
your kidding!? My 68 has a curly copper line. Have not had any problems with it so far....
My 68 has a curly copper line. Have not had any problems with it so far....
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Originally Posted by LemansBlue68
When connecting the oil pressure line in my '68 I saw that the original setup called for a copper line running directly from the engine to the gauge inside. For fear of dealing with the same problem you are experiencing, I went with a '69 style oil line connection. This uses a copper line about 1' long that connects from the pressur tap hole from the engine near the oil filter, and leads up to a bracket that mounts to the back of the cylinder head. Attached to the bracket is a fitting that connects the copper line to a black plastic line. The black plastic line leads into the passenger compartment and connects to the the gauge. I debated about the "Factory correct" installation vs. making the upgrade, but the fear of hot engine oil spilling all over hot exhaust manifolds won out over "FCR".
The black plastic line will tolerate much more flexing as the engine moves and vibrates than will a copper line. Copper has a tendency to work harden as it flexes causing it to become brittle over time.
The '69 up oil line kit is available from Paragon.
The black plastic line will tolerate much more flexing as the engine moves and vibrates than will a copper line. Copper has a tendency to work harden as it flexes causing it to become brittle over time.
The '69 up oil line kit is available from Paragon.
