Top frame rear allen head bolts

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red107
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Top frame rear allen head bolts

Post by red107 » Mon Jan 28, 2019 3:55 pm

I'm in search of the top frame rear allen head bolts. Or if someone knows another option.
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Re: Top frame rear allen head bolts

Post by fp55scca » Mon Jan 28, 2019 6:38 pm

red107 wrote:
Mon Jan 28, 2019 3:55 pm
I'm in search of the top frame rear allen head bolts. Or if someone knows another option.
-------------------------------------------------------
--Robert, just to be clear, are we talking about the allen head bolt that attaches the main hoop of the top to the chassis?
Jim Scurria
Norfolk, VA

1972 Fiat 124 Spider
1971 Spider - SCCA FP-24
1974 CSA Abarth Replica
1981 Fiat Spider Ratrod
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red107
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Re: Top frame rear allen head bolts

Post by red107 » Mon Jan 28, 2019 6:45 pm

Yes, two per side.
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Re: Top frame rear allen head bolts

Post by fp55scca » Mon Jan 28, 2019 9:56 pm

red107 wrote:
Mon Jan 28, 2019 3:55 pm
I'm in search of the top frame rear allen head bolts. Or if someone knows another option.
-----------------------------------------------
--Ok Robert, I'll check around and see if I can rustle some up for you. Where are you located?

--Just for info, I believe those bolts are 10mm x 1.25 thread pitch, and about 30-35mm in length under the head. But, there are two reasons to want to use the correct bolt. One, the heads are tapered to fit flush in the frame; and second, the proper bolts are somewhat pointed because they have to go through the top frame, and then catch a captive nut in the chassis.
Jim Scurria
Norfolk, VA

1972 Fiat 124 Spider
1971 Spider - SCCA FP-24
1974 CSA Abarth Replica
1981 Fiat Spider Ratrod
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red107
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Re: Top frame rear allen head bolts

Post by red107 » Tue Jan 29, 2019 12:32 pm

Jim, I sent you a private message.
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Re: Top frame rear allen head bolts

Post by fp55scca » Fri Feb 01, 2019 10:01 am

--Robert, still working on locating your top frame attaching bolts. The reason I'm familiar with these is that I just had a problem with my own, and had to use my spares. If anyone else can locate some, please chime in here.....

--I'm also investigating whether or not the door latch, striker plate bolts at the B-pillar might be the same, or at least a suitable substitute for the original top frame bolts. Again, if someone else can comment here, please join in.
Jim Scurria
Norfolk, VA

1972 Fiat 124 Spider
1971 Spider - SCCA FP-24
1974 CSA Abarth Replica
1981 Fiat Spider Ratrod
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Re: Top frame rear allen head bolts

Post by fp55scca » Sat Feb 09, 2019 11:58 am

--Ok Robert, looks like the door striker plate bolts are the same as the top frame attaching bolts. Both tapered and 10mm x 1.25 thread pitch.

--The question now is do you have the large, thick washers (about 10mm thick) that go between the frame and the chassis? I'm thinking that if you're missing the bolts, you may be missing the washers as well? Without these washers installed, the top frame will bind on the chrome trim strips at the base of the rear windows.

--This is the bolt: tapered head, and tapered threads to engage the captive nuts in the chassis.
Top Frame Bolt.jpg
Top Frame Bolt.jpg (74.61 KiB) Viewed 1390 times
Jim Scurria
Norfolk, VA

1972 Fiat 124 Spider
1971 Spider - SCCA FP-24
1974 CSA Abarth Replica
1981 Fiat Spider Ratrod
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red107
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Re: Top frame rear allen head bolts

Post by red107 » Fri Feb 22, 2019 3:40 pm

i'm not missing the bolt. They are just worn out and pretty much stripped out. I don't have the washer on the inside of the frame either.
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Re: Top frame rear allen head bolts

Post by fp55scca » Sat Feb 23, 2019 6:13 pm

--Robert, this could be a simple case of replacing the bolts and washers; but, if your bolts are "pretty much stripped out", then you may also have damaged "captive nuts" in the chassis? Have you tried to insert a 10mm x 1.25 thread-pitch bolt into the "chassis captive-nuts" just to be sure the threads are still good? If you try this, be very careful, go very slowly by hand, and stop if you start feeling too much resistance.

--In either case, you will still need the bolts and washers, but no sense in trying to screw a good, clean bolt into a stripped-out captive nut. You might be able "chase the threads" in the captive nut if you find them damaged, but the problem is this: because it is a "captive nut", as you apply force to the nut to either screw in a good bolt, or to chase the threads, the force can "spin" the captive nut in the chassis....then you are screwed. This can also happen when inserting bolts in damaged captive nuts. You might get them in, but you may not get them out again.

--The only proper fix, is just like the captive bolts in the frame that hold the crossmember, you will need to cut out the damaged captive nuts, and weld in new ones. This takes welding equipment (MIG), and a little fabrication skill. Let us know what you find. I just had to do this "myself" (for a body-shop no-less), after one of their young, aggressive guys cross-threaded the captive nuts on my 72 Fiat Spider, while trying to insert the bolts for the top-frame with an air-tool....!
Jim Scurria
Norfolk, VA

1972 Fiat 124 Spider
1971 Spider - SCCA FP-24
1974 CSA Abarth Replica
1981 Fiat Spider Ratrod
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Re: Top frame rear allen head bolts

Post by red107 » Sat Feb 23, 2019 7:20 pm

Thanks for the heads up, My captive nuts are fine. I have access to a parts car. But the top bolts were worst than mine. I will look at the striker screws.
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