Got a leak on the 1983 242 high pressure fuel line leaving the fuel filter heading towards the front of the car. I have already made my own fuel line in 2014. So I am sure if what to do. I notice these push together unions specifically for 8mm OD nylon tube fuel lines (www dot autozone dot com/fuel-systems/fuel-line-repair/dorman-oe-solutions-8mm-nylon-fuel-line-unions-2-piece/433294_0_0). Seems too good to be true and I am not sure how/if they will work on the line as there is some bend in this section as the line leaves the back of the fuel filter and heads forward. There is not much slack to play with. Any comments? Thanks

PS - seems they make them in 90 degree too (www dot amazon dot com/Dorman-800-322-Nylon-Degree-Connector/dp/B00K5A9C2C/ref=sr_1_48?dchild=1&keywords=dorman+nylon+fuel+line+union&qid=1587067303&sr=8-48&swrs=7E7DF501E6789F5919DD62958C7CEA0C)

Sorry I seem to be unclear here. There are URLs in the first post that clearly identify what I have used and am talking about here. Just change the dot to . In some cases I have seen these called unions and in other connectors. They are for splicing a cut nylon fuel line. And I am talking about the hi pressure side of the line. Cheers

I just finished removing about 1/4" to 1/3" where the line was leaking and splicing it using one of these 90 degree nylon union fittings. I had my doubts about if this would hold up to the almost 80 psi my fuel pump is supposed to deliver on my '83 242. But it was much quicker and easier than the alternatives. So far, it is holding just fine. Not a drop of fuel leaking. I ran the car here in the drive and around the neighborhood. Hope it continues to hold. I also got some of these straight ones . But it turned out that the leak was along the curved section where they would not have worked as well. Also, using the 90 degree one, I had plenty of fuel line available. So maybe a good weapon to add to our arsenals.

The push on fuel line connectors at the tank sending unit used in the 940s are plastic. If that’s the kind of thing you’re talking about then I’ve never heard of failures and always felt it was a positive lock, providing of course there's no dirt on the connector and they're not subject to much motion. Can’t really imagine them being a weak point at the pressures we’re talking. 30 psi in a 1/4” line is barely a half pound force, so that’s the kind of strength those fittings need to have.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

before my current 10 Volvo,,ive had,,,I had a Ford e-150 Supervan w a Straight 6.lots like my previous dependable Chevy Nova s& 1 Pv544. Inline enegines.150 had a 300 Cube 6,,fed by plastic lines & really easy to change fuel filter. Pull the fuse,Push in on the elbow & pull out clips catch the fuel in a pan,& then disconnect the filter .Push on the elbows,place the clips & its done,,Dont have to worry about getting new copper seals

Hi David,

I'm not sure what you're describing here. In the plumbing world a union is a 3 part fitting used to join threaded pipes. It's used where there may be a need to de-couple the joint easily.

The title of your post, "Nylon Fuel line Unions" makes me think you're splicing nylon fuel line, but then later in the post you mention a "nylon union", suggesting the fitting itself is nylon.

Volvo uses barbed metal push on connectors in many 240's that have nylon lines, and they stand considerable pressure. I have a 1990 that the previous owner drove for a year with failed FPR. The failure allowed full pump pressure, over 100 psi I believe, on the system. The car ran like crap, but the fuel lines were fine. I think it's likely that Volvo engineers took the eventuality of such a failure into account when making their design choices.

regards, Peter

BTW - I checked with the maker to see what, if any, pressure spec there is on these unions. Their response was "Our fuel fittings are tested up to 90psi". So it seems this could be possible to use on my 1983 240 FI line.