I just went through is on my 83 Turbo. Look at Art's post, lots of good info there, especially about not nicking the barbs. I used 8mm OD, bought from McMaster-Carr in the 25' length, and used every bit of it.

The heat method didn't work for me though. After heating it with a heat gun and getting the barb in, looked perfect, reinstalled everything, LEAK! Try doing that several times, talk about being P.O.'d.

With the heat method I could not control how tight the tubing would clinch the barb. I went with the wood block method, made with OAK.

Drill a hole slightly smaller than 8mm, through the block, saw through the block lengthwise bisecting the hole, install wood screws at all four corners, then at one end enlarge the hole so it will except the barb and tubing. It should be a little bit deeper than the barb, so it doesn't get pinched at the end. Put the block in a vice with the tubing flush with the larger opening, Now tap in the fitting. If the tubing wants to slide, put some vinyl tape on it and reclamp it.

The process is called SWAGING, that's what worked for me.


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Bruce S. near D.C.