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Tapping a hole for the TB mod?

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Old 03-12-03, 01:44 PM
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Tapping a hole for the TB mod?

On the Throttle Body mod when you remove the front butterflies for the choke assembly, it is common practice to JB weld or use a similiar apoxy to seal off the hole that remains when you remove the shaft that holds on the butterflies. I have heard that the JB weld when put under stress of an engine has cracked into peices, the peices have than got into the engine and caused catastrophic engine damage. I was wondering if I could tap the whole and use a pipe plug instead. If any body has done this Please reply, or if there is another alternative way without using the JB weld apoxy let me know.
Old 03-12-03, 01:50 PM
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I used a 1/8NPT tap and an 1/8NPT plug to seal the hole, worked great.
Old 03-12-03, 02:11 PM
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The easy way and just as effective is to fill it with JB Weld, preferably the kwik set.
Old 03-12-03, 02:47 PM
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The best way is to use a tap and plug like 1FastT2 said. However, I also recommend putting thread sealant on the plug.
Old 03-12-03, 02:51 PM
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Originally posted by RX-Heven
The easy way and just as effective is to fill it with JB Weld, preferably the kwik set.
Unless it is done properly JB weld has been known to fall out in more than one occurance, and into the intake tract and enventually the motor.
Old 03-12-03, 02:55 PM
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You wouldnt even need to fill the hole to get it to work with JB Weld You could just apply it to the outter edge of a dime and it would seal just as well. If you wanted extra assurance (as I did) you could then seal the inner opening with high temperature silicone RTV sealant.
Old 03-12-03, 02:59 PM
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If I were using JB weld I would probably slot the hole to keep it from sliding into the tb. However a tap is like 4 bucks, a plug is like 1.50, and thread sealant is around that. Do the job properly.
Old 03-12-03, 03:08 PM
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Originally posted by Icemark
Unless it is done properly JB weld has been known to fall out in more than one occurance, and into the intake tract and enventually the motor.
I forgot there are some incompetent people out there.
Old 06-03-03, 12:59 AM
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If you tap and plug the hole, I'm sure the plug doesn't seal it perfectly (as far as fitting the contour of the inside of the tb), it would either go into the tb, or leave a little "crater". Those who have plugged it, what did you do, just leave a crater? Would this affect air flow?
Old 06-03-03, 01:06 AM
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Originally posted by RotaryRevn
If you tap and plug the hole, I'm sure the plug doesn't seal it perfectly (as far as fitting the contour of the inside of the tb), it would either go into the tb, or leave a little "crater". Those who have plugged it, what did you do, just leave a crater?
Yep
Would this affect air flow?
Not near as much as the throtal plates did.
Old 06-03-03, 01:38 AM
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Thanks, that's what I was thinking
Old 06-03-03, 03:49 AM
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Re: Tapping a hole for the TB mod?

Originally posted by chris406
I was wondering if I could tap the whole and use a pipe plug instead. If any body has done this Please reply...
This is actually the recommended method, and I'd say over half of the people here who've done the TB have used this method.

I took my TB to a mate's workshop and tapped an M10 thread into the hole, then found an M10 SS bolt to fill the hole. I used threadlock on the threads and a little sealant under the bolt's head when it sat against the TB just to be sure of no air leaks.
Old 06-03-03, 08:05 AM
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Originally posted by nillahcaz
Yep

Not near as much as the throtal plates did.
If a small bit of a bolt sticking into the path bothers you, I'm pretty sure a rotary grinding bit may help remove the obstruction.
Old 06-03-03, 10:15 AM
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is there a site with a write-up and pics of this mod. i've seen several "How-To's" but i never see this mod.
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