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TR4/4A Wrong Threads on New Fuel Pump?

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KVH

KVH

Obi Wan
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The new fuel pump I've had in my trunk for years appears to have threaded extensions on each fitting inlet/outlet. Do those come off? I see the threading is different and neither of the fittings on my fuel line will work.

It appears I must now get new brass fittings on the line?

I wasn't expecting yet another surprise, but OH WELL. Is this considered an improvement due to the original brass fittings no longer being available in original thread?

Thanks all.
 
A photo, or some information on what pump you bought might help ...
 
Here's the Pic. Surprised, but no big deal. Moss said the manufacture was bad in the year I bought this, and that they had adaptors added so that they would properly seal. However, I was also told that the threads in the fittings would still be original. I was told there was no change. That's not so from what I have on my car. The age old brass line nut is a different thread. It might even be metric. It won't fit into the pump, so I'll make a new line section and just use what Ace Hardware sells. FYI, last year I brought my TR line nut around town and no one had a match. I just assumed we'd better keep our old fittings. I can't recall if I was told it was metric, some pipe thread, or some other variation. But I'm stuck without some shop fabrication.

photo.jpg
 
Sorry for the waste here, but after removing all fittings and examining the pump and threads, and comparing to original, I see that the only change in the pump from original stock was that Moss had the "fix" made to the pump by adding the two extension pieces during the manufacture period in question. Around 2009. The issue, however, was leaking at the "olive" fitting, not a thread change.

New pumps will not have those extensions. The new brass fittings I bought were perfect, but what I said about the new pump threading (or my fitting threads) was wrong. All were stock, standard. The problem was just me--the new angle created by the extensions and some imperfections on my old lines. Anyway, just so the facts are corrected. The new pump was fine, albeit with those odd extensions.

On a related topic, TRF tells me they're done with cheap pumps and that we won't find them selling $39 dollar replacements anymore. Too many quality issues. Just fyi.
 
All my pumps including my spare are old ones that I have rebuilt as needed.

Like radiators and other original parts, the cost of a water pump rebuild may equal or exceed the cost of aftermarket repro parts - but is often the better plan.
 
Geo Hahn said:
All my pumps including my spare are old ones that I have rebuilt as needed.

Like radiators and other original parts, the cost of a water pump rebuild may equal or exceed the cost of aftermarket repro parts - but is often the better plan.
Click to expand...

I wholeheartedly agree. I'd also like to see Harry Truman as President again.
 
Glad you got it sorted. I meant to look up whether the 4A pump is identical to the earlier cars or not; but didn't get a chance. I don't have the 4A SPC scanned yet and got roped into one of SWMBO's projects before I could find the paper version. At least on the earlier pumps, the inlet and outlet threads are standard SAE; the problem is that the original compression ferrule was shaped differently than modern ones are and the nut (even a new replacement) can't crush the modern ferrule far enough to seal before it hits the bottom of the threads.

Here is one man's solution https://drive.google.com/file/d/0B2...NzhmLWEyYmYtOGJhMzgxZWI5YTUz/view?usp=sharing

What I did was to turn a nut with an extended tip (kind of like the brake line fittings) so I could use a standard ferrule.
 
KVH said:
I wholeheartedly agree. I'd also like to see Harry Truman as President again.
Click to expand...
"America's calling Harry Truman;
Harry you'd know what to do.
The world is turnin' 'round; losin' lots of ground.
Oh Harry is there something we can do to save the land we love ?"
 
So can someone tell me what the correct thread is? I can state defininitively that it is NOT 1/4-BSPT, nor 1/4-BSP. Two weeks and two incorrect fittings later. I'm trying to run stainless steel fuel lines to my webers. Any insight appreciated-- jim
 
TRF has both the 1/4 and5/16" pipe nuts. I can provide you with the part number if you want it.

Charley
 
I think we figured it out: 1/2-20 SAE compression. Will post further once I verify. Jim
 
I just want to clarify something in case the thread is unclear:

I first said the threads in my new pump were different from the original. But on May 6 I then saw and noted here that I was wrong. Only the fitting housings had been changed, and that was just due to temporary manufacturing issues.

The threads were, in fact, standard SAE, I believe exactly what Jim says, and I believe the compression fitting is readily available at Ace or your auto parts shop.

My original confusion was all created by two things: a) the imperfections in the fuel line catching on the inside of the line-nut housing; and b) the awkward angle of the fuel line where it bends and comes back into the pump housing from the block side. Anyway, hope it's now clear. Those pump fittings are neither metric, nor pipe thread. Just SAE compression.
 
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