Exhaust Replacement - 1981 VW Rabbit Diesel

by marc.cryan in Workshop > Cars

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Exhaust Replacement - 1981 VW Rabbit Diesel

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Replace the exhaust system on a VW rabbit.  

I could not find much info on the details of installing a muffler.  Hopefully this will help if you have to do the same thing

This was physically difficult for me to do, a lot of being under the car, which I don't like.

Note: The red bentley manual as a good exploded view, it also has the torque spec for the pipe clamps ... although I seem to have lost it.... you can get them from amazon here  

Get the Parts

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This is a complete replacement exhaust with accessories and tools.

Document Part Numbers

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I photograph all the labeling as soon as I open the boxes.  If you need a part number latter, it is easier to look at the pictures then at the top of a muffler that is under a car.

Practice Assembly - Pipe Clamps

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Spring Clamps and Tool

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Rubber Hangers

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Gasket for Down Pipe 'toilet Bowl'

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Yikes - What a Big Thing

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Inspect the Pathway and Hangers Under the Car

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Remove the Old Down Pipe

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Use the spring clip removal tool, to remove the spring clips.  I tightened it as much as possible and still could not remove the clips.  I oiled the area around the clips and was then able to remove them.

Will reuse the heat shields.

Not sure if there is a small crack in the exhaust manifold -- does not look like damage, but does not seem like it should be there.

Jack Up the Back of the Car and Get a Light

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Install the Tail Pipe and Muffler -- Needs to Be Snaked Into Place

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Secure With Rubber Hangers

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Deal With Rust

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Rust sucks.

Chip and Cut Away All the Rust

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Hitting the rust with a hammer will get rid of a lot of it.  Using a pointy hammer works well and helps you figure out where the edges of the rust are.

I used an angle grinder with a cut-off disc to cut back to good metal.

To weld you need a clean surface, so go around the edges with a wire  brush disc on the grinder.

Patch the Hole With Sheet Metal

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I used 22 gauge steel and a 90amp wire feed welder from Harbor Freight.

To get the right shape I first cut a scrap piece of aluminum (bottom of a 'catering tray') then traced the shape onto the steel.  I used nippers to cut out the shape, this is sort of a pain, but it does work.

Welder settings: MIN Power  and Wire Speed 2

Weld the new piece in place.  22 gauge is a bit thin, 18 gauge would have been better.  18 is the minimum thickness that should be used with this welder.  Had to patch a few holes after putting in the large piece.

Transfer the Heat Shield to New Down Pipe

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Install Down Pipe With Spring Clips

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Here is how I got it to work.
  • First installed passenger side clip from under the car.
    • Held up the downpipe with my knee while attaching the clip
  • Install driver side clip from above the car.
    • I was able to pull the bottom of the pipe towards the drivers side, stretching the passenger side clip.  This  made it possible to install clip.  
    • It was hard to get the clamp off
Here is a link to the socket set I have Stanley 97-126 11 Piece 1/2-Inch Drive Metric Deep Impact Socket Set  

Install Middle Muffler Part...

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This was the easiest part.  The middle part of the exhaust hangs by one clip and attaches to the two other pieces.

Seal Joints and Tighten Clamps

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I'm worried I did this wrong, somehow.

The sealant was messy, most of it squeezed out of the joint.


Straighten Everything Out

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Probably should have done this before sealing and clamping the joints....

I was able to get everything lined up okay by twisting the muffler.  You want to get the pipes so they are close to the bottom of the car, not hanging down all over.

Done for Now

Run the engine and check for leaks.... I guess.

As long as it doesn't fall off I'm happy for now.  In the end it will have to pass a 'smog test', should be fine.