-AN Fuel tank fittings Options

[GrayMatter]

I did a quick search and came up empty. Has anyone tried these? I’m wondering if they will fit our fuel tanks.

http://www.dansperformanceparts.com/sand/s...ing-to-6an.html

[McMark]

The one issue I have, even if it fits, is the stock fitting has a sock screen and a tube riser that this would eliminate.
The riser stops rust, water (from moisture) and crap from entering and plugging the fuel line.

These can be used with the sock and riser (with the 'lower' portion cut off flush with the 'washer'. Just installed one.

McMark - you mention don’t use a washer? Not sure I understand why not. The original fittings use them from what I remember. Either way, loctite is a good call and I’ll definitely be doing that.

The washers in the stock arrangement are there because those are all that's sealing the fuel inside. With these adapter fittings, the threads are the sealing surface, and the Loctite 565 (which is fuel safe) ensures a complete seal. Furthermore, rubber washers can break down in fuel. The car I mentioned above was getting worked on because the fuel pump died. The fuel pump died because the rubber washer deteriorated and a piece lodged in the pump.

[jd74914]

McMark - you mention don’t use a washer? Not sure I understand why not. The original fittings use them from what I remember. Either way, loctite is a good call and I’ll definitely be doing that.

The washers in the stock arrangement are there because those are all that's sealing the fuel inside. With these adapter fittings, the threads are the sealing surface, and the Loctite 565 (which is fuel safe) ensures a complete seal. Furthermore, rubber washers can break down in fuel. The car I mentioned above was getting worked on because the fuel pump died. The fuel pump died because the rubber washer deteriorated and a piece lodged in the pump.

I might not be understanding what you're referencing, so ignore if you are taking about something different, but why do you think the threads on the M18-AN adapters are sealing? If it's still attaching to a non-tapered thread you technically need a sealing washer. I get that you can make it all seal up with some pipe dope, etc. but that doesn't make it correct on a straight thread fitting. Finding a fuel-compatible washer should be pretty easy if the supplied ones have compatibility issues.

[McMark]

I might not be understanding what you're referencing, so ignore if you are taking about something different, but why do you think the threads on the M18-AN adapters are sealing? If it's still attaching to a non-tapered thread you technically need a sealing washer. I get that you can make it all seal up with some pipe dope, etc. but that doesn't make it correct on a straight thread fitting. Finding a fuel-compatible washer should be pretty easy if the supplied ones have compatibility issues.

I agree 100%... with the addition that we're installing two technically incompatible fittings. That adapter is not designed to seal the way the original fitting is. So yes, you could find sealing washers. That's not hard, and if you think that's the way to go, I got nothing but respect for that. But that's also not the 'right way', IMHO. If I was gonna design this part to work 'right', I would spec a fiber washer (probably original) and CAD the fitting with the washer included to make sure there's enough threads to ensure correct crush of the washer.

I think it's presumptuous to assume that this fitting would seat correctly against a stock fiber washer in a way that would create a correct seal. Maybe it does, but I've seen enough adapters and 'custom' parts to be skeptical of making an assumption as big as that.

So rather than spending a bunch of time reverse engineering a stupid fitting, I just added a fuel safe sealant that has to stand up to 0 psi and seal a gap of around 0.01". I think Loctite 565 is well up to the task of those conditions.

But as I said, if you disagree or want to go another way, do it. Just report back here so we can all learn together. (IMG:style_emoticons/default/thumb3d.gif) (no sarcasm)