Oil Pressure Line

[tim71]

I’m curious about the oil pressure line on the 72 Blazer that I am rebuilding. The oil line has a rubber casing around it, while my 71 K1500 oil line is just bare copper line. Both have a sbc 350. Are both correct for their year?

[Thealien]

I have had a couple of Blazer’s and Jimmy’s with the rubber coating around the copper oil pressure line. I’ve also had a couple without it. Who knows what happened over the course of the last 50 years? But I do believe at least some came factory with the rubber hose covering the copper line?

[Steeveedee]

Oil pressure lines, iirc, are steel from the factory. Copper work hardens and gets brittle and cracks. I suspect that the cover is to stop corrosion and/or nicks. If I ever replace my oil pressure gauge tubing, it'll be with a wire. The truck has had one engine rebuild and still has the original line, as far as I know, though.

[LockDoc]

Originally Posted by Steeveedee

Oil pressure lines, iirc, are steel from the factory. Copper work hardens and gets brittle and cracks.

This is not always true. The refrigeration copper tubing that I use for my oil lines does not work harden. It is specifically made for refrigeration applications where there is a lot of vibration and other movement....

Copper tubing Specs

Product Details. This MUELLER INDUSTRIES copper refrigeration tubing easily connects air conditioning and refrigeration equipment.• Connect using sweating or flare fittings• Copper tubing is nitrogen purged to reduce contaminants

Technical Specs: Item Copper Tubing. Tube Material Copper. Tube Size 1/8". Inside Dia. 0.065". Outside Dia.1/8". Wall Thickness 0.030". Max. Pressure 3074 psi. Tube Length 50 ft. Copper Tube Type ACR. Copper Tube Shape Coil. Soft/Hard= Soft. Application Refrigeration. Copper Tube Coating None. Temp. Range 100 Degrees to 400 Degrees F. Standards ASTM B280, ANSI B9.1
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LockDoc

[tim71]

Originally Posted by Steeveedee

Oil pressure lines, iirc, are steel from the factory. Copper work hardens and gets brittle and cracks. I suspect that the cover is to stop corrosion and/or nicks. If I ever replace my oil pressure gauge tubing, it'll be with a wire. The truck has had one engine rebuild and still has the original line, as far as I know, though.

You are correct about the line being steel. Both of mine are steel, the 72 has the rubber protection. I misspoke when I called it copper, I was picturing the screw in fitting.

[Sheepdip]

Originally Posted by LockDoc

This is not always true. The refrigeration copper tubing that I use for my oil lines does not work harden. It is specifically made for refrigeration applications where there is a lot of vibration and other movement....




LockDoc

LockDoc is correct this is known as annealing a heating/cooling process that gives copper ductility, annealing is also used in electrical wire manufacturing to make it flexible

[truckster]

I don't recall any of mine having a rubber coating, but I can't say for sure that they didn't.

[LockDoc]

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I have original steel lines with and without the rubber sleeve. Also, some lines were one piece and some were two piece with a union connector in the middle. It may have been dependent on which supplier supplied the oil lines for a certain assembly plant.

LockDoc

[HotWheelsFan]

Rubber around the oil pressure line is common on 1973 and later years... I do not know when it was introduced.

I do believe it serves as vibration dampener. In my experience, less engine noise is transferred into the interior of the vehicle when used.


Bob