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Old 05-13-2017, 10:57 AM   #1
54blackhornet
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Removing Original Exhaust , V8 Tips ?

Need help ! What's the best method to remove down pipe assembly from a stock V8 ? Unbolt system from manifolds or should I just cut the pipes off and unbolt the manifolds ? The manifolds have never been removed before. The collector bolts attaching the pipes to manifold look pretty rusty and how the hell do you get a wrench on them ? Plan on replacing original single system with dual setup....thanks for any suggestions....
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Old 05-13-2017, 11:30 AM   #2
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Re: Removing Original Exhaust , V8 Tips ?

Before you do anything...I would seriously soak all the fasteners and nuts down with liquid wrench (or equivalent) and leave them for a full day or two.
After soaking them I would give them a few taps or a little bit of attempted torque to help the liquid wrench penetrate.
One thing that often helps a fastener 'break free' is when you alternate between trying to loosen it and tighten it. Sometimes a turn towards tightening it up makes a big difference in it then being willing to untighten.
When you do put a wrench or socket it on it, use a '6 point' if you can....not a 12 point (socket)....which would be more likely to 'round the head' off....and stay very far away from using an 'adjustable wrench'.
Anyhow, with respect to the liquid wrench stuff....I would do this at least a couple of times....but start early, and be patient and let it do a bunch of the work.
If you try to do this all within the next 15 minutes without preparing it probably won't go well.

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Old 05-13-2017, 11:54 AM   #3
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Re: Removing Original Exhaust , V8 Tips ?

Thanks ! Already been applying BP Blaster for the last few days. My big decision is , should you just cut off below the collectors and remove the manifolds or try to disconnect the headpipes from the manifolds ? Figured it would be easier to undo the connections at the manifold on the workbench ?
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Old 05-13-2017, 12:34 PM   #4
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Re: Removing Original Exhaust , V8 Tips ?

I'd say if you want to reuse the down pipe, don't cut. If not reusing it, cut away and save years off the end of your life due to frustration.
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Old 05-13-2017, 02:48 PM   #5
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Re: Removing Original Exhaust , V8 Tips ?

You should be able to remove the nuts from the manifold studs with a deep well 6 point socket, using the back and forth method mentioned. If the nuts have never been removed, one or more of the studs may break. It would be better to remove the manifold if you have to drill out the stud(s). I've done them in place when I worked as a mechanic, because time is money and I didn't like charging that kind of money for a repair. Its just a little dirtier, is all.
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Old 05-14-2017, 07:14 AM   #6
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Re: Removing Original Exhaust , V8 Tips ?

Seldom is there a nut that won't come off if you heat it cherry red before you remove it.

Have your socket and extension and ratchet ready. Heat the nut till it glows. Remove nut. If you're working a little slow and the nuts cools down, it will start to squeak as you turn it. If so, stop and reheat before proceeding. Repeat as many times as necessary to get the nut all the way off.

A real torch is best, but if you're patient, a simple propane torch from the hardware store will eventually put enough heat into it to get the results.
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Old 05-14-2017, 07:36 AM   #7
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Re: Removing Original Exhaust , V8 Tips ?

No matter what you do, it sounds like time for new studs. You might want to pull manifolds for that. If you can save the pipe for your exhaust shop to model after it would be a good thing. If you decide to cut, do so back once it's leveled out. The red wrench is your friend.
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Old 05-14-2017, 06:38 PM   #8
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Re: Removing Original Exhaust , V8 Tips ?

I cut mine. They were too much of a pita
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Old 05-14-2017, 06:50 PM   #9
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Re: Removing Original Exhaust , V8 Tips ?

I recently pulled my Y pipe off my 307 and it was the first time it had ever been off. I used a deep 6 point socket as mentioned with a long extension from down below. Whichever studs didn't break unscrewed from the manifolds (those nuts were never coming off!), and my Y pipe dropped right out. I ended up having to replace the manifolds because they were both cracked. New manifolds and studs made reassembly very nice.
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Old 05-19-2017, 10:57 AM   #10
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Re: Removing Original Exhaust , V8 Tips ?

I really appreciate everyone's suggestion's ! In the process of trying to unbolt the Y pipe from the manifolds first.
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Old 05-19-2017, 11:32 AM   #11
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Re: Removing Original Exhaust , V8 Tips ?

I have an extra set of mid-length hedman headers laying around BTW.
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