Help !!! snapped thermostat houseing bolt
#1
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Help !!! snapped thermostat houseing bolt
hey guys,
I was changing my thermostat the other day and the damn bolt snap. I had a buddy come look at it for me he said he could fix it so he drilled it out and tried to tap it but the f'in tap didnt cut any threads it just drilled out a bigger hole . what am i suppose to do can i get it welded and how much do you think it will cost to do so. any help is much appreciated.
Thanks
87Irocz
I was changing my thermostat the other day and the damn bolt snap. I had a buddy come look at it for me he said he could fix it so he drilled it out and tried to tap it but the f'in tap didnt cut any threads it just drilled out a bigger hole . what am i suppose to do can i get it welded and how much do you think it will cost to do so. any help is much appreciated.
Thanks
87Irocz
#2
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Car: '86 TransAm WS6
Engine: 305 TPI
Transmission: Custom TH700R4
Hey, wow, that happened to me this weekend, too!
I got a Heli-Coil kit from my autoparts store, that goes like this:
Purchase Kit (3/16)
Drill specified (25/64) hole (provide your own drill bit)
Using supplied tap, cut new threads
Using supplied driver, install HeliCoil insert
Install new bolt
I have an aluminum TPI manifold, so tapping the threads was pretty easy.
What happens when you try to drill out a bolt, and then re-cut the threads is that the drill tends to chew up the threads in the hole, and there isn't much left to tap in to. The HeliCoil kit puts a high strength steel insert in, so that they won't rip out. If some thing happens, and the bolt seizes to the insert, it wil rip out and you just screw in a new one.
In order to prevent this from happening again, I repace every bolt I remove with ARP stainless fasteners, liberally coated with ARP thread sealer grease. ARP stainless bolts get expensive, but they're worth it. At the least, I reccomend the thread sealer, it makes it much easier to remove the bolt in the future.
I've used HeliCoils of all sizes, and I trust them for just about any bolt replacement.
If you're nervous about cutting threads, get a chunk of aluminum or steel and drill some practice holes.
Good luck, let me Know how it goes...
I got a Heli-Coil kit from my autoparts store, that goes like this:
Purchase Kit (3/16)
Drill specified (25/64) hole (provide your own drill bit)
Using supplied tap, cut new threads
Using supplied driver, install HeliCoil insert
Install new bolt
I have an aluminum TPI manifold, so tapping the threads was pretty easy.
What happens when you try to drill out a bolt, and then re-cut the threads is that the drill tends to chew up the threads in the hole, and there isn't much left to tap in to. The HeliCoil kit puts a high strength steel insert in, so that they won't rip out. If some thing happens, and the bolt seizes to the insert, it wil rip out and you just screw in a new one.
In order to prevent this from happening again, I repace every bolt I remove with ARP stainless fasteners, liberally coated with ARP thread sealer grease. ARP stainless bolts get expensive, but they're worth it. At the least, I reccomend the thread sealer, it makes it much easier to remove the bolt in the future.
I've used HeliCoils of all sizes, and I trust them for just about any bolt replacement.
If you're nervous about cutting threads, get a chunk of aluminum or steel and drill some practice holes.
Good luck, let me Know how it goes...
#3
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ahh, That same thing happened to me on my old caprice. But I broke both bolts. But I didn't have any problems fixing them. Quick and simple drill and tap fix.
How did you buddy get you a bigger hole? Use a cutting wheel to cut the broken stud flush with the intake, then get a center punch to make sure you drill down the center of the bolt. Use a smaller size drill bit. And when you are tapping, you can't just twist the thing all the way down, you have to cut a little then twist the tap out some to get the loose shavings out.
Just try tapping the bigger hole, no need for weilding.
How did you buddy get you a bigger hole? Use a cutting wheel to cut the broken stud flush with the intake, then get a center punch to make sure you drill down the center of the bolt. Use a smaller size drill bit. And when you are tapping, you can't just twist the thing all the way down, you have to cut a little then twist the tap out some to get the loose shavings out.
Just try tapping the bigger hole, no need for weilding.
#4
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i know this is repetitive, but it happened to me last summer what i did was:
using a 4.5" grinder, gind the bolt (whatever is left) flush with the manifold. center punch the center.....very important...THE CENTER of the remaining bolt. i used a bit the same size as the original bolt and drilled it out. then went one size higher so i had a fresh start with the tap. its important to lubricate the tap or it wont cut right. i used a few drops of plain old motor oil. choose the right size for the hole, and very carefully make sure it is straight and give it a few turns. as you feel it to begin to cut the threads, back it out a few turns to clean the tap of all the metal shavings. then cut some more turns of threads, and then back it out to clean it again, then tap some more, and more until finally, you get to the bottom of the hole. replace the broken bolt with a new one, and dont forget the anti seize!!!
sorry so long, hope it helps. when i did mine, it was over 100* outside. not fun. later
using a 4.5" grinder, gind the bolt (whatever is left) flush with the manifold. center punch the center.....very important...THE CENTER of the remaining bolt. i used a bit the same size as the original bolt and drilled it out. then went one size higher so i had a fresh start with the tap. its important to lubricate the tap or it wont cut right. i used a few drops of plain old motor oil. choose the right size for the hole, and very carefully make sure it is straight and give it a few turns. as you feel it to begin to cut the threads, back it out a few turns to clean the tap of all the metal shavings. then cut some more turns of threads, and then back it out to clean it again, then tap some more, and more until finally, you get to the bottom of the hole. replace the broken bolt with a new one, and dont forget the anti seize!!!
sorry so long, hope it helps. when i did mine, it was over 100* outside. not fun. later
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