I'VE GOT A 94 CARB THAT HAS A STRIPPED LARGE THROTTLE BODY SCREW...THE 1/4 x 28 . WHAT'S THE BEST WAY TO REPAIR IT?
These times if you can't find H-coil. Farmer fix is; clean hole out ,JB weld {or Epox}a stud in hole let dry 2 days,then put back together with a nut an lock washer
Dana knows,,,,,he’s been in this game for some time . And I don’t know any farmer that likes metric ,,,,LoL. Tommy
90% of the World's Farmers use Metric threads on everything they own. Of course they live outside the USA. The only country of any note still using the Imperial system.
I generally want to take a closer look at things before I decide how to fix them. Sure, helicoils are great in many cases, but they can also be completely unsuitable in other places. For example, you don't want them in spark plug holes, as they may stick to the plug while being screwed in, and get pushed far into the combustion chamber without you knowing.
The first thing to try is to simply and carefully re-tap it with the 1/4 x 28 thread. Sometimes this works for low load screws where the threads may be damaged instead of completely gone. The tap can restore the thread height by swaging the damaged threads back up to where they will hold. On the other hand, if thread damage is severe and the tap starts....”off thread” you’ll end up with a very smooth hole. There’s other things you can do but ‘94 cores are rather common.
I like the JB Weld idea too. I tend to wax up a bolt, fill the hole/threads as needed, get the bolt in and don't monkey with it til the next day. Unscrew the waxed bolt and get back at it like it never happened. there's other "liquid metal" repair mediums out there too that are really tough. As to why fix, well the one you have might be better than what you find. And FWIW, WE'RE ALL BORED AND LIKE A HAPPY ENDING. TELL US HOW YOU FIXED IT WHEN YOU DO. I typed it that way so you know I was paying attention
While a heli-coil will work in this instance................. Unless this is one very rare Holley 94 that I never heard of, or one that extensive racing modifications have been made to, just throw it away, and start with another. Much cheaper than buying the heli-coil tool. If you already have the heli-coil tool, then its 50-50 whether the paragraph above still applies. Not going to argue the J. B. Weld, but I have yet to fix ANYTHING with this stuff that stayed fixed over 6 months. At my age, fix it once, and forget it; every 6 months (or less) doesn't cut it. Jon.
I've used this stuff on some smaller screw holes and it worked OK. Loctite Form-A-Thread Stripped Thread Repair Kit 236382 Not as strong as Helicoil, IMO, but may be strong enough for the carb.
IF you decide to 'pour & fix', there is an aluminum epoxy that machinists use. This stuff is infallible, can be drilled, tapped, and is harder than aluminum. DEVCON 'aluminum putty'...#10610. I bought an aluminum intake for one of my SBCs, it had 3 tapped holes that were so damaged I couldn't heli arc them, (wasn't 'secure' in trying!) My machinist son gave me this product, said they use it to repair errors on production parts that have hours of 'events' (production machining) too costly to reproduce. I tried it...Holy Moley! Not a 'believer' in JB Weld, glues, or other 'self-hardeners', I was a hard sell...'til I tried it. Miracle stuff. And they understate it as 'putty'! I filled the holes per instructions, then Vixen (blade) filed it flat. Drilled just like the parent material! Tapped smoothly, I was amazed. Thank you, Sonny.
The only country of any note still using the Imperial system ! Yeah,,,you’re right,,,,I guess we are kind of backwards over here . But,,,,,,no matter where it is ,,,,,when someone needs help,,,,who do they look to . Right here ! Tommy
Devcon is the answer. But, also a nutsert/ezlock...a threaded sleeve....drill oversize...of course if there is enough base metal....tap accordingly.....screw in nutsert/ezlock sleeve sized to the original thread size....this is the penultimate if there is enough base metal. Done this many times in aluminum head holes for rocker stands. The process makes the hole / threads more better than original. Sent from my XT1710-02 using The H.A.M.B. mobile app
Right now the Devcon seems like the permanent fix. I have a helicoil set but I want it to last, so...! As I'm sure most of you know that this screw is the only one that inserts from the bottom of the front of the triangular throttle body into the float bowl of the main body. I just spent a couple weeks rebuilding this baby so I won't throw it out and get another one. I'm not a farmer anymore, but I don't think the old farmer would put a nut into the float bowl! Well maybe the farmer of the day would. These new ones would just throw it away and buy a new one!! Thanks to all you guys for the assist and I will get back to you with the fix if I can find some Devcon on Google or Amazon. Thanks again.
The kits are expensive, but the inserts can be bought separately and don't cost much. Using Devcon will probably cost you at least as much as the insert. If you already spent weeks rebuilding it, at least I would for sure use a one dollar insert to make a proper repair here too.
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