Fuel injection line thread sealant

[Mark280SL]

Hi Gents,

One of my fuel injection lines on my 1970 280sl is leaking fuel at the head end creating the risk of fire so I have purchased a replacement set of lines.  I’m assuming I should use some type of gasoline resistant thread sealant at each threaded end when I install the new line but not sure.

Not wanting to ask a nuisance question that’s already been answered I’ve done several searches in the forum looking for mention of a sealant but my searches haven’t resulted in any answers so I’m wondering if someone could point me in the direction of the answer if I should use a sealant on the threads and if  so is there a preferred product, I’ve looked online and found products that seem like they would fit the need but want to be careful to be sure I don’t use something that might be inappropriate.

Any info would be greatly appreciated.

[Jack the Knife]

Tuning into this, as I had my lines out for a while...

[BHap]

I’m pretty sure the lines are sealed with a flare on the pipe and a backing nut, so sealant should not be needed.

[Pawel66]

I am not a mechanic, but what I heard and learned - sealant is an enemy of fuel injection. Sealant particles may block it.

Everything from FIP up is self-sealing flares. Some connections below FIP are fitting, hose and clamp.

If you, however, are looking for sealant to seal some fuel related place - you need sealant rated for gasoline. I use Hylomar, but not on my Pagoda.

[Pinder]

should not need sealant.

[waltklatt]

No sealant was used.
Make sure the conical male head is smooth and free of blemishes, scratches, burrs....
Also make sure the receiving female side is also the same-free of any -as above-.

Ensure the threads are straight, not crossed.

Walter
1967 220SL diesel
1969 280SE(new motor and subframe mounts)
2003 Beetle TDI
2005 Honda Element

[wwheeler]

Make sure the alignment of the cone into the female end is good. Does the tightening nut freely screw down or does it have to be wrenched the whole way. The nut should not be in a bind and if so, the line could be misaligned and a possible cause of the leak. No sealant needed as been said.

But you may want to put a VERY small dab of anti seize on the tightening nut threads and also where the nut contacts the fuel line. Those two areas can be become corroded and make removing the fuel line in the future a hard job. Just be very conservative with the anti seize  and don't get it where it makes contact with the fuel flow.