Datsun Roadster Forum-311s.org

I'm sorry everyone, I'm sure this has been answered but I'm just not finding it.
Does anyone know what the size of the fittings are for the fuel supply line at the tank? I need to replace the hard line from the tank to the filter. From my searches and measurements, I've got a 1/4 feed and 5/16 return lines with what I think are double flares. I was just going to use the old fitting at the tank end but I wouldn't mind replacing it with something new. I know some are using AN fittings. I just don't know the size/pitch.
Any help appreciated.

Matt

My 70 pl the main looks 5/16 or 8mm with the 1/4" calciumed up S bend connection off the tank . But doubtful you can get that apart and back today .

Well, after taking off the line and a quick trip to the local ACE to use their bolt template (I really need to buy one of those) the verdict is.....
7/16-20 for the 1/4 inch supply line. If I end up replacing the return line I'll post the size for that as well.
As an aside, has anyone tried successfully to flush the crud from the fuel lines? I noticed that Eastwood sells an aerosol injected cleaner for this sort of thing but at $22 per can I decided to go the cheaper and guaranteed route with a new line.
This is what I started with.

Some el cheapo carb cleaner in a can and some fine stiff wire plus time and effort will clean that sucker out.

Nissanman wrote: ↑Tue Mar 07, 2023 6:31 pm Some el cheapo carb cleaner in a can and some fine stiff wire plus time and effort will clean that sucker out.

Thanks, I considered that route and may still do it with the original lines, just to have them, but this car and I have a history of sorting out fuel issues since I picked it up last year. The sludge in the tank was impressive and took quite a bit of cleaning. I got a few months in with great results but then another slug showed up in the filter and I started having issues. When drawing fuel through the line with a vacuum pump, after blowing out the line with compressed air, there were still quite a few bubbles. I got the impression that it might be the way the fuel was flowing around the obstructions.
More importantly, there's a Japanese Auto Legends event at VIR on 3/11 that I wouldn't mind attending. Hopefully I'll have things sorted out by Saturday.

Get an old speedo or tach cable inner. Chuck it into a drill and using carb cleaner as a lubricant, go to town on that thing. It will be clean as new inside.