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Steer Clear!

Thunderlugs

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While the 62-65 manual steering box is getting some attention, I need to know who would know the CORRECT size for the fill plug. The threads on mine are partially gone AND cross threaded. I spoke to the people at Firm Feel, (Great People) and they say it is an oddball size and they prefer if possible, I make the repair before sending it to them, for rebuilding. That little defect is something they would not likely do. I am looking for the best recommended fix. Hopefully just an oversize pipe plug. Thanks in advance Thunder
 
While the 62-65 manual steering box is getting some attention, I need to know who would know the CORRECT size for the fill plug. The threads on mine are partially gone AND cross threaded. I spoke to the people at Firm Feel, (Great People) and they say it is an oddball size and they prefer if possible, I make the repair before sending it to them, for rebuilding. That little defect is something they would not likely do. I am looking for the best recommended fix. Hopefully just an oversize pipe plug. Thanks in advance Thunder
I can't help with the fill plug, but you may want to oblong the bolt holes in the steering box (manual I assume) before installing. By doing this, you can slightly move the box toward the fender...and allow a bit more room for headers. the modification is not detectable once done. I think we moved our's about 7/16" which helped with the 2" headers. Nice car.
 
I measured the thread count on mine and it's a 24 thread. The threaded area is tapered so that's telling me it is pipe. I tried to find something to match it in my trusty fitting drawer and could not find anything close.

You could take it to a quality plumbing store and see if there is anything that matches up. Maybe hit the junkyard to find another one?

If the threads in the housing are crossed also you'll have to chase them with the right tap. Or find a new plug with a close enough thread, buy the tap that matches it and redo. Just throwing some options out there.

One more, get yourself a thread file with a #24 and they will clean up pretty good if they're not chewed up too bad.
 
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I measured the thread count on mine and it's a 24 thread. The threaded area is tapered so that's telling me it is pipe. I tried to find something to match it in my trusty fitting drawer and could not find anything close.

You could take it to a quality plumbing store and see if there is anything that matches up. Maybe hit the junkyard to find another one?

If the threads in the housing are crossed also you'll have to chase them with the right tap. Or find a new plug with a close enough thread, buy the tap that matches it and redo. Just throwing some options out there.

One more, get yourself a thread file with a #24 and they will clean up pretty good if they're not chewed up too bad.
Thanks for the input Kid, But I see now after re-reading my post I did not explain it correctly. My problem is with the threads in the Box not the plug itself. I picked up a 3/8 npt plug which is slightly larger than the oem plug,with coarser threads. I could try to drill and tap the hole but i think it will fit to loosely. Should I think about a Helicoil? or is the housing just too shallow. In a Kinundrum. Thanks for your input though. Thunder
 
Thanks for the input Kid, But I see now after re-reading my post I did not explain it correctly. My problem is with the threads in the Box not the plug itself. I picked up a 3/8 npt plug which is slightly larger than the oem plug,with coarser threads. I could try to drill and tap the hole but i think it will fit to loosely. Should I think about a Helicoil? or is the housing just too shallow. In a Kinundrum. Thanks for your input though. Thunder

I was trying to understand how the treads on a steel plug got messed up in an aluminum hole but things happen.

Do you know of a reputable machine shop nearby? Most of the ones that I worked in had a good assortment of taps and could match what you have.

Useing the coarse pipe thread might work since it was fine thread before. You could buy a short tap for the job. I was thinking about how far the tap needs to go before it would come in contact with the internal parts. When it gets rebuilt the shavings from tapping should get cleaned out hopefully.
 
Really surprised F/F wouldn't fix it. Will they take it all disassembled so you could have it fixed. Just have the next sized plug put in. Are you sure it a pipe thread?
 
Really surprised F/F wouldn't fix it. Will they take it all disassembled so you could have it fixed. Just have the next sized plug put in. Are you sure it a pipe thread?
You Know I never considered that it might not be pipe thread.That is why I come to the Think tank. I will check out that option . Thanks
 
I don't have one in front of me, if it becomes to much drama just find the closest pipe thread plug that's slightly larger and drill and tap it.should cost ya under $20 bucks
 
While the 62-65 manual steering box is getting some attention, I need to know who would know the CORRECT size for the fill plug. The threads on mine are partially gone AND cross threaded. I spoke to the people at Firm Feel, (Great People) and they say it is an oddball size and they prefer if possible, I make the repair before sending it to them, for rebuilding. That little defect is something they would not likely do. I am looking for the best recommended fix. Hopefully just an oversize pipe plug. Thanks in advance Thunder
This is curious and had to do a bit of research. Checked my reliable old machinists bible (machinery's handbook) and could find no listing of any pipe thread w/ 24 tpi. Either NPT or NPS. Even checked dry seal pipe thread & fine (F-PTF), British std pipe threads (both press joint & non-press joint. 24 tpi, nada. Pipe threads (small to large) in tpi: 27,18,14,11 1/2, 8. A 3/8 pipe thread measures about 5/8" (depending on where you measure) and a 5/8" extra fine (unef) has a 24 tpi count, but that's a machine thread (no taper). Chrysler could have made up some special tooling just for this application, but why? A dryseal pipe thread would have worked just fine. Are you sure the threads are tapered?
 
I think if you actually get a pitch gauge you will find this plug is a 3/8" x 24 National FINE thread.
Through all the bs written, clarify, it is the housing that is messed up, right? Then you need a helicoil to fix it. Fastenall or similar professional supplier should have it available.
Maybe a replacement box may be cheaper, and I have one I can sell.
 
I think if you actually get a pitch gauge you will find this plug is a 3/8" x 24 National FINE thread.
Through all the bs written, clarify, it is the housing that is messed up, right? Then you need a helicoil to fix it. Fastenall or similar professional supplier should have it available.
Maybe a replacement box may be cheaper, and I have one I can sell.
Yes the housing is the entire problem.
 
I had mine out the other day and the plug is tapered but not as much as a pipe plug. It's probably just a 24 thread. If he would find that tap it might just work.
Thanks Kid...I need to sort through all the options before me and make a F..n decision. If repairing the housing doesn't work well, I will just have to find another box and send it to FF for refreshing.
 
I think if you actually get a pitch gauge you will find this plug is a 3/8" x 24 National FINE thread.
Through all the bs written, clarify, it is the housing that is messed up, right? Then you need a helicoil to fix it. Fastenall or similar professional supplier should have it available.
Maybe a replacement box may be cheaper, and I have one I can sell.
Good info, I will see if i can find one(helicoil) and proceed. If not I might take you up on your offer.
 
While the 62-65 manual steering box is getting some attention, I need to know who would know the CORRECT size for the fill plug. The threads on mine are partially gone AND cross threaded. I spoke to the people at Firm Feel, (Great People) and they say it is an oddball size and they prefer if possible, I make the repair before sending it to them, for rebuilding. That little defect is something they would not likely do. I am looking for the best recommended fix. Hopefully just an oversize pipe plug. Thanks in advance Thunder
Gonna bore people w/ more general info. I don't pretend to know everything about threads but in my career I have cut quite a few and repaired a lot of them. Worked in both the oil/gas industry & aviation. Here's a bit of general info on pipe threads. Pipe is measured by the I.D. (inside dia) & tubing is measured on the O.D. (outside dia). There are several classifications of pipe threads but the most common ones us car nuts will encounter are npt (national pipe tapered) & nps (national pipe straight). If you have ever taken apart a table lamp or floor lamp then that hollow tube in the center (the one where the wire runs) is either a 1/8 or 1/4 nps thread. Measurement for some common npt plugs (Measurement taken at largest dia): 1/8 "npt- just under .400" (betw 3/8 & 7/16), 1/4" npt- .525", 3/8"npt-.665". Heli-coil for pipe threads? Not saying they don't make them but I've never seen one. Knowing how a pipe thread is cut (holding correct depth is critical) & how they seal I don't know if it would be feasible. Now back to the steer-box problem. Is it possible that the box had a machine thread (unf or unified national fine) w/ a plug that had a shoulder & washer on it? Haven't had a Mopar w/ manual steer in decades so I can't remember. Any-way hope someone can use info on threads, lot of misunderstanding there.
 
I think you would be fine to just chase the threads in the hole with a #24 x whatever that diameter is. 3/8" or 1/2"?, tap. It's just a plug to keep the grease in. A heli-coil wouldn't be necessary.

Mine doesn't use a washer, probably why the slight taper on the plug itself.
 
Gonna bore people w/ more general info. I don't pretend to know everything about threads but in my career I have cut quite a few and repaired a lot of them. Worked in both the oil/gas industry & aviation. Here's a bit of general info on pipe threads. Pipe is measured by the I.D. (inside dia) & tubing is measured on the O.D. (outside dia). There are several classifications of pipe threads but the most common ones us car nuts will encounter are npt (national pipe tapered) & nps (national pipe straight). If you have ever taken apart a table lamp or floor lamp then that hollow tube in the center (the one where the wire runs) is either a 1/8 or 1/4 nps thread. Measurement for some common npt plugs (Measurement taken at largest dia): 1/8 "npt- just under .400" (betw 3/8 & 7/16), 1/4" npt- .525", 3/8"npt-.665". Heli-coil for pipe threads? Not saying they don't make them but I've never seen one. Knowing how a pipe thread is cut (holding correct depth is critical) & how they seal I don't know if it would be feasible. Now back to the steer-box problem. Is it possible that the box had a machine thread (unf or unified national fine) w/ a plug that had a shoulder & washer on it? Haven't had a Mopar w/ manual steer in decades so I can't remember. Any-way hope someone can use info on threads, lot of misunderstanding there.
Yeah no luck on the Helicoil. Here's the deal, the top half of the threaded hole has no threads at all, chewed away, "Gone". the bottom remaining 1/8 " that has threads, are cross threaded. Nothing to really work with. So , I am forced to go oversize. the 3/8 npt is really my only choice. 37/64 drill. , tap it and see how shallow the threads are. If it doesn't work I will have to find another box. Finding another good candidate box......well I guess I will cross that bridge when I get to it. Thanks for your input. Thunder
 
Yeah no luck on the Helicoil. Here's the deal, the top half of the threaded hole has no threads at all, chewed away, "Gone". the bottom remaining 1/8 " that has threads, are cross threaded. Nothing to really work with. So , I am forced to go oversize. the 3/8 npt is really my only choice. 37/64 drill. , tap it and see how shallow the threads are. If it doesn't work I will have to find another box. Finding another good candidate box......well I guess I will cross that bridge when I get to it. Thanks for your input. Thunder
I have not done anything yet. Just taking it all in. Such a simple thing ,is a ******* pain in the ***!
 
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