Said It Here

How to install tight new fuel lines on fittings

New rubber fuel lines are often extremely difficult to push fully onto metal connection fittings by hand. Softening the hose in boiling water can help, but failing to get the line all the way on creates a risk of leaks and improper sealing during vehicle maintenance.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    holding the hose in boiling water to soften it
  2. 2
    applying a little motor oil or engine oil to the inside of the tip
  3. 3
    using a grinder or knife to bevel the inside of the hose
  4. 4
    cutting the end off to get a clean edge
  5. 5
    Using hose clamps to secure the partially seated line and checking for leaks after startup.
  6. 6
    Using stainless steel hose clamps that are resistant to rust
  7. 7
    Using a dedicated fuel line repair kit
  8. 8
    Slightly flaring the metal tube with a flaring kit to secure the clamp

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/MechanicAdvice2 people · September 2026

AI tells me fuel injector clamps however that's what I had on before and they ended up rusting and leaking. Surely there's a better way to go about it? It's just a thin rubber tube and thin metal tube where the rubber one sheaths over. Or is the fuel injector clamps just standard?source ↗

transformed-software · r/MechanicAdvice · 4 upvotes

Put new fuel lines on my 2009 Honda shadow spirit 750cc, it’s low pressure where the lines are. But I couldn’t get it fully on, do you think this will be ok?source ↗

Immediate-Cycle3763 · r/MechanicAdvice · 2 upvotes

Is anyone able to give me some advice on how to get new fuel lines on, they are very tight and this keepssource ↗

Immediate-Cycle3763 · r/MechanicAdvice · 1 upvotes

It should be the same size as I measured the previous one that was on there but I’ve never put one on before so might not be doing it right, I’ve held it in boiling water for a couple mins to soften itsource ↗

Immediate-Cycle3763 · r/MechanicAdvice · 1 upvotes

Where this came up

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