Reply To: TD20 In-Tank fuel filter (w/screen) pt# 375663???

[John Gragg]

frankr wrote:

In the first place, those are not 5/8 and 1/2 inch threads.  They are tapered pipe threads.  Pipe sizes harken back to the days of iron pipes and are sized according to the INSIDE diameter of the pipe.  Even that is not totally true, as iron pipes were made with over-size ID to allow for full flow in spite of clogging with rust buildup inside.   Since you think it is 1/2″, I assume it is really 1/4″ NPT (National Pipe Thread).  Next size down, 1/8″ NPT is often mistaken for 3/8 at first glance (not).

I don’t see the problem with the screen.  Are you concerned with the seam that runs the length of it?  It would be simple to just re-solder it.  It may not even be necessary, if the seam lies reasonably tight together.

Pipe threads have always confused me a bit, but I thought I was ‘safe’ when I measured the tank hole by testing a 1/2 x 20 tap so I could get a proper plug at the hardware store. How is it that the tap matches the threads, but you are calling it something entirely different?

I called the threads 1/2″, is that incorrect? If it is, what size threaded plug would I go to Ace and look for? 🤔 please edumacate me?

I tried resoldering the seam. Even pre-heated the mesh. Solder would not stick, as clean as I got the mesh. I even tried using flux paste to clean the mesh, no dice. Ended up making more of a mess.

thx

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

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