Backwards hose barb..wtf?

Per my other thread, I’m in the process of converting backwards from the TevesIII brake system to a conventional vacuum boosted system.
Since I have owned the car, every time I’ve changed the fuel lines, the return line, which runs from the fuel cooler to the barb on the left fender well, has been a PITA. The barb is buried under the anti-lock gear and it’s always really hard to push the hose on. I’ve tried a couple of different metric and standard hose sizes, it’s either too big or too tight. I always end up going with a tight fit and muscling it on there. Today, while fabbing up new brake lines, I needed to remove the fuel line to make some room. Easy to do, now that the Teves gear is out of the way. I did a double take when I got a good look at the barb for the first time. The barbs are backwards. Never seen that one before. No wonder it fights me every time.

That may be the mechanical equivalent of the upside-down airplane stamps!

New one on me!

Yeah, that’s pretty weird.

There’s another weird barb on a very tiny bit of hose in the liquid line of the freon circuit between the filter/dryer and the expansion valve, actually right under the radiator top rail. The sucker is sorta waisted, narrower in the middle than at either end. And a real #$%^ to push a new piece of barrier hose onto.

you do realize that UK engineeres have an unusual sense of reality!
there way or no way!
ron

Does this have anything to do with driving on the left-hand side of the road, or the dream in the sink swirling backwards?

Never seen nor heard of that.
It’s not just weird, it’s Top Ten weird.
Now that you’ve found it, I am wondering if others have it, or it’s just a manufacturing error. I’m passing that picture on.

Theory #1: This is a solid fuel line. Maybe its 3 pieces: The main line, the barbed section, and the big barb on the end. Maybe they are brazed or soldered together, and someone put the barbed section in backwards.

Why not cut that crazy fitting off and put on a straight fitting barbed on both ends for the correct hose size ? The one you have has to be a machining glitch. SD Faircltoh

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I will at some point. It’s right on the bulkhead so no room to work with it in the car. I’ll pull the whole line, perhaps when I am doing the trans swap.

Matt Furness posted this pic of a cut-open fuel cooler. Look close at the barbs:

https://forums.jag-lovers.com/uploads/short-url/6YBBfUz3MLBv3496ObZ2ekmmT5X.jpeg

Here are two pictures of the Series III XJ6 fuel rail hose barbs.

It sure looks like the barbs are designed to make it more difficult to get the hose on than off. Very odd!

Paul

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It’s not a one-time machining error, then. That leaves only two possibilties: It’s either a long-running uncorrected design error – like the cross hole location on the banjo fittings – or it’s deliberate. Anybody have any ideas why a designer would deliberately do this?

Somewhere, some lurker is going, "*HAH!!!

They finally noticed! Muuuuuuahahahaha!!"

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the only thing I can figure out would be: that 1. you should have a clamp…2. that it was meant that if you had to remove it it would not grind against the inside of the hose for two possible reasons…a. preserving the hose…b. not having rubber scrapings get into the system…and if that is any of the reasoning, then A. …Jaguar over-engineered again…or B…some kind of justification for job security…or C… most probably that no one really knows

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I got nothin. Clearly the end that goes into the fuel line / fuel cooler solders in place. I wanna known if the main barb or nipple on the other end also solders on. In other words, is it a machining error, or an assembly error where the part with the small barbs is reversed.

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Going with “C”.

I’m usually pretty good making up answers, for weird stuff like this.

I gots nuthin’.

Maybe SD Faircloth will reply to give his perspective?

Paul

Paul, He (David F) did reply earlier in this thread

He did, but he went for this being the exception and it might not be.

Here is a photo of mine off an 85 XJS. Same thing.image