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So I finished flushing the system and went to put the bolts back onto the thermostat housing and found out one them is stripped. I rented a tap and dye set from auto zone and couldn't get it to start making threads. Im using a 7/16x14 tap and drilled the hole a lil smaller then that. Anyways going to try it again on friday see if I can make it happen. Can i get rid of these heater hoses and cap off the water pump? If so what do you guys recommend i use?

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You may need to put a helicoil or thread insert in that t-stat housing. If you buy the kit at the auto parts store, they usually have the needed drill bit and tap you need in the kit.

I have never done so, but I would think just get the pipe fittings to fill those holes. Summit or Jegs has them, maybe a local Napa.

Good luck, just make sure you tap straight, otherwise you new threads will be crooked too.
 

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Discussion Starter #3
You may need to put a helicoil or thread insert in that t-stat housing. If you buy the kit at the auto parts store, they usually have the needed drill bit and tap you need in the kit.

I have never done so, but I would think just get the pipe fittings to fill those holes. Summit or Jegs has them, maybe a local Napa.

Good luck, just make sure you tap straight, otherwise you new threads will be crooked too.
I was looking into that helicoil. The part I was having problems with is starting the threads every time I turned it, the tap would pop out of the hole, if that make sense. If I can't get it I think I'm going to buy a new intake.

Do you know if I can cap off holes on the water pump and the one on the intake?
 

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Unless you were getting a new intake anyway don't get another just cause of that. You can Heli-coil it. Maybe the hole you drilled is not quite big enough for your tap. As stated if you get a little kit it will have the drill size you need. Use a little cutting oil when you thread the tap in and back out every little bit. Should be able to find a You-tube video to show you how. Real easy. Yes, you can to plug those holes and get rid of the heater hoses.
 

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Discussion Starter #5
Ya i want to avoid getting a new intake, cuz I do not want to deal with taking things apart. So when drilling the hole you want to drill the hole the same size as the tap. So if I'm using a 7/16 bolt I want to use a 7/16 drill bit?
 

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No, the bit will be a little smaller than the tap you are using. You will actually be drilling the hole larger to install the heli-coil with the inside thread size you need. Sorry my explanation is confusing. :turn: Maybe somebody will chime in that will explain it better than me. If you get the kit with the heli-coil, heli-coil install tool and drill bit you will understand.

YouTube video link not coming up. Just type this in to youtube:

Thread Repair - How to install a Helicoil

Drill bit size chart:
http://www.thedirtforum.com/hdc.htm
 

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Where is all the metal shavings going when you drill and tap?

I would put grease on the tap/drill to catch the shavings as much as I could and

then get a vacuum to get the rest after your done.

Dave
 

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Press Down Hard

Use a Pipe Tap first and Press Down Hard with your hand on the tap handle. Make sure you keep it aligned. Make sure it's a Pipe Tap, and you may need to be careful. .

If you can find a Starter Pipe Tap that would be nice too, but I'm not sure such an animal even exists...
 

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Watch this video. Not the best but shows you what he is doing. Type this in YouTube:

Using Heli Coil to fix stripped bolt hole intake manifold


You are tapping a blind hole so take your time and remove the shavings as you go. As said keep it straight. Just work slow, take your time, you'll be fine. I thought it was a 3/8" bolt but it's been a while. Just take the bolt with you to the hardware store. Tell em you want a Heli-coil kit to repair the threads that bolt goes in.
 

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You can get your heater hose plugs while there. Here's mine. I can't remember the size just take your old one with you.
 

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The original bolt would be a 3/8' coarse thread. A helicoil kit will have everything you need. Another thing to consider is using a threaded stud instead of a bolt so in the future you can remove the nut and leave the stud in the manifold. Just a quick thought......you could possibly get a stud that is 3/8'' on one end and 7/16'' on the other. Tap the hole to 7/16'', screw the stud in and have a 3/8'' stud protruding for the stat housing.
 

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Hello,

Check Summit Racing and Jegs and search for a 3/8X16 Heli Coil kit, it includes the correct size drill bit, a 3/8 X 16 tap and 6 heli coils.

From memory, the short bolt is 3/8-16X1" and the longer bolt is 3/8-16X1 1/2"


Heli-Coil P/N 5521-6 - Heli-Coil Thread Inserts
 

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Discussion Starter #14
thanks guys for your responses. Ill report tomorrow how it goes
 

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So I finished flushing the system and went to put the bolts back onto the thermostat housing and found out one them is stripped. I rented a tap and dye set from auto zone and couldn't get it to start making threads. Im using a 7/16x14 tap and drilled the hole a lil smaller then that. Anyways going to try it again on friday see if I can make it happen. Can i get rid of these heater hoses and cap off the water pump? If so what do you guys recommend i use?

IMG_7068 by https://www.flickr.com/photos/[email protected]/


Tap drill size for a 7/16 tap is a U drill (.368) for aluminum. You can use a 25/64 (.390) for a 7/16 in steel. You already have a 3/8 hole that is threaded in the intake I would drill with a 3/8 (.375) drill and try to start the tap.
 

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Since it seems you've never tapped holes before, it would be wise to do some trial tapping on some material before doing the intake. Practice makes perfect(or satisfactory). Taps are very brittle and take no side forces. Keep the tap 90° to the hole as you go. Use lubrication and any sudden increase in resistance as you thread means you have to reverse the tapping before continuing.
 

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Discussion Starter #18
Tap drill size for a 7/16 tap is a U drill (.368) for aluminum. You can use a 25/64 (.390) for a 7/16 in steel. You already have a 3/8 hole that is threaded in the intake I would drill with a 3/8 (.375) drill and try to start the tap.
thats what a buddy of mine suggested i use a u drill. Not sure why Im having so much trouble but i will try that. Thanks for the help.
 

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I rented a tap and die set from auto zone and couldn't get it to start making threads. I'm using a 7/16x14 tap and drilled the hole a lil smaller then that. Anyways going to try it again on friday see if I can make it happen.
So when drilling the hole you want to drill the hole the same size as the tap. So if I'm using a 7/16 bolt I want to use a 7/16 drill bit?
There are charts out there for what is the proper sized hole for when using a particular tap and you need to not guess at having the hole a you call it as a "lil" smaller than what is needed.

I have to wonder when renting things how abused a tool was and was any parts replaced like a drill bit because one got broke and the guy returning it replaced it with one he had laying around ?.

I know some times it's money out of your pocket but maybe think about buying a new bit with a new tap. I did this while back on a job and I already had the tap handle and oil and the install went very well. I had things at the house but the customer paid for using new so that's what I opted for.

Sometimes you have to apply a little pressure to get the taps going into a hole and you have to keep things square.

Also keep in mind there are different tap designs and you do not want to start tapping a hole with a bottoming tap.

When you tap holes or thread round stock, run it in a turn or two and back it off to break off the chips and then run it in a little more and then what I do it remove the tap, clean or wash off the chips, blow out the hole and then get back onto it some more.

Jim
 

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possibly the taper on tap is to long and bottoming out before it starts cutting,if so you will need a bottoming tap to get threads to bottom of hole
 
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