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Solenoid nuts!

angelfj1

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Anyone know what size these nuts are and where I might get a couple? Are they Whitworth?
nuts.jpg
 
Frank - they're certainly not Whitworth on mine. Just used SAE (don't remember the size).

By the way, your engine bay is much too clean. I can ship you some grime and grit at a very affordable rate!

Tom
 
They are definitely a special thread (and width) on my TRs, although I don't recall what offhand. I kind of think maybe 0 BA, but might be 1/4 BSF instead. I can check in a few hours, if no one else knows.

Once you come up with the size, you can probably find a suitable substitute at https://www.britishfasteners.com/mm5/merchant.mvc
But I'm guessing they won't look exactly like the originals (which are thinner than standard nuts).

My solution was to find an original solenoid and rob the nuts from it. Eg,
https://cgi.ebay.com/ebaymotors/TR3-TRIUM...sQ5fAccessories
 
NutmegCT said:
I can ship you some grime and grit at a very affordable rate!

Tom

No thank you, Tom.
BTW, did you plant a large victory garden this year?
Brings back memories of Jim Crocket on public TV?
 
TR3driver said:
They are definitely a special thread (and width) on my TRs, although I don't recall what offhand. I kind of think maybe 0 BA, but might be 1/4 BSF instead. I can check in a few hours, if no one else knows.

Once you come up with the size, you can probably find a suitable substitute at https://www.britishfasteners.com/mm5/merchant.mvc
But I'm guessing they won't look exactly like the originals (which are thinner than standard nuts).

My solution was to find an original solenoid and rob the nuts from it. Eg,
https://cgi.ebay.com/ebaymotors/TR3-TRIUM...sQ5fAccessories

That's a good idea. thanks, Randall!
 
angelfj said:
TR3driver said:
They are definitely a special thread (and width) on my TRs, although I don't recall what offhand. I kind of think maybe 0 BA, but might be 1/4 BSF instead. I can check in a few hours, if no one else knows.

Once you come up with the size, you can probably find a suitable substitute at https://www.britishfasteners.com/mm5/merchant.mvc
But I'm guessing they won't look exactly like the originals (which are thinner than standard nuts).

My solution was to find an original solenoid and rob the nuts from it. Eg,
https://cgi.ebay.com/ebaymotors/TR3-TRIUM...sQ5fAccessories

That's a good idea. thanks, Randall!
yes, or copper plated
 
TR3driver said:
They are definitely a special thread (and width) on my TRs, although I don't recall what offhand. I kind of think maybe 0 BA, but might be 1/4 BSF instead. I can check in a few hours, if no one else knows.
Just curious, Randall: does what you say hold true for both styles of solenoid? There was a change around 1959-60 from a solenoid with integral mounts to one with a separate mounting "ring" (like most coils have). I took a quick glance at my later-style solenoid just now, but I couldn't tell by looking what the threads are. :wink:
 
I looked at the one I have in the garage I got off ebay. It's just like the one that came on the car that was flooded -except the ebay one works. And the other difference is that someone threaded 24tpi steel nuts on, and re-tapped the copper. 24tpi is close, but not exact. It's the closest from the guages I have, but 20 and 27 are next in my set. -I know this doesn't answer your question, but it does say what it isn't.
 
Oops, my mistake. I checked both an early and late style solenoid, the threads are actually 5/16 BSF (22 tpi) on both of them. There may be some out there with SAE threads, but these were definitely BSF.

The nuts appear to be steel, about .182" thick and .440" across the flats (making them also undersize, to fit a 1/4" BSF wrench). Might have been cad plated originally, but no sign of that or any copper plating. (Cad plating corrodes away over time, but copper would have still been showing if it was there originally.) The studs are solid copper (or copper alloy) though.

BTW, that "separate" mounting ring is spot-welded to the main case (which is steel on the later solenoids rather than the pot metal found on the earlier ones).
 
Frank, the cable fixing nuts on the solenoid were the same as those already on it holding the threaded posts in place.

Sometimes auto electrican shops have boxes of odds and ends, and might have the nuts you are looking for.

Regards,

Viv.
 
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