If you can't get the plastic line as Art suggests below, the compression union to copper may still be an option.

I believe the hard plastic line is the same OD (8mm is very close to 5/16"). And I recall someone here seeing or buying 5/16" compression unions in an Autozone-type store that were packaged/sold for use with plastic tubing. I think you could make a leak-free plastic to copper connection with them.

My confidence comes from having done several successful copper-to-Bundy tube section replacements using those common compression unions.

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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

If yours is the black nylon line, your 83 must be a non-turbo, B23F engine.

Try a dealer or Tasca Volvo. I'm squinting at my parts fiche, coming up with p/n 1312382 for which Tasca's discounted internet price is $35. This seems a little too reasonable to me. I had thought these were more like $80, so be sure to speak with a parts professional and be certain I've given you the correct number.

I would probably take one off a car in the junkyard. The trick is to use a swift mallet blow to the box end wrench when loosening the banjo bolt at the filter, and saving the brute force for squeezing the 14 and 17 line wrenches together up at the rail. But hey, at $35, the new part could be tempting.

Here I am trying to demonstrate a two-handed job with one holding the camera. One thumb should hold the box wrench over the bolt head (banjo bolt on the filter in your case) while striking the other end of the wrench against the counterhold of inertia. Or use an air tool.


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Art Benstein near Baltimore

Marriage is a wonderful institution, once you are ready to be institutionalized. - R. Cooke