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problem with exhaust manifold

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Old Apr 16, 2017 | 11:49 AM
  #1  
robersonb's Avatar
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Rock Crawling
Joined: Jun 2012
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From: Maryville, TN
Default problem with exhaust manifold

So I have to change my CPS sensor. Started loosening the bolts to drop exhaust off the manifold. Did the trick with warming the truck, soaked bolts and was a gentle as I could be. Didn't have an impact gun to use. One sheared off. Left a good amount clear, actually just shy of enough to still get the bolt on. What is the best way to get that out and put a new one in? Preferably without taking it off the head.

Going to go ahead and try and get CPS changed while I listen to any suggestions you guys may have.

The one thats on there is only aobut 6 months old from an engine rebuild although it was used (shout out to Paul Grant for great service and parts).
 
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Old Apr 16, 2017 | 11:53 AM
  #2  
abran's Avatar
Baja
Joined: Aug 2013
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From: Huntington Beach CA
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Soak with deep creep by sea foam for a day, use a propane torch the next day to heat, then use a stud extractor.



Performance Tool W83203 Stud Extractor | eBay
 
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Old Apr 16, 2017 | 12:46 PM
  #3  
OffroadFrance's Avatar
Joined: Aug 2013
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From: Near Bordeaux, France
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Originally Posted by robersonb
So I have to change my CPS sensor. Started loosening the bolts to drop exhaust off the manifold. Did the trick with warming the truck, soaked bolts and was a gentle as I could be. Didn't have an impact gun to use. One sheared off. Left a good amount clear, actually just shy of enough to still get the bolt on. What is the best way to get that out and put a new one in? Preferably without taking it off the head.

Going to go ahead and try and get CPS changed while I listen to any suggestions you guys may have.

The one thats on there is only aobut 6 months old from an engine rebuild although it was used (shout out to Paul Grant for great service and parts).
The cast iron manifolds have a bad habit of warping and even shearing the holding down studs. The best option is to resurface the manifold face in a milling machine as a new manifold will inevitably warp again sooner or later. By resurfacing the manifold it is highly unlikely to ever warp again. There is also a kit to convert the existing studs to headier diameter studs but on a V8 I'd reckon it's not possible with the heads insitu. Tuning of any type increases the manifold temperature and increases the likelihood of warping.

I can speak on the subject from experience, albeit a TD5, I've been there and done that, sheared studs and all.

Cast iron castings are unstable and the heating and cooling releases stresses which results in warping.

There is an article and fix in LR Monthly on the subject of warped manifolds.
 
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Old Apr 16, 2017 | 01:52 PM
  #4  
robersonb's Avatar
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Rock Crawling
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From: Maryville, TN
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I'm not sure if your speaking of the suface that meets the head but mine sheared off of the joint to the exhaust. I do not intend to take it off the heads and risk shearing another at the heads if I don't have to.
Going to try the crep oil and heat and see if I can't get it out.

Originally Posted by OffroadFrance
The cast iron manifolds have a bad habit of warping and even shearing the holding down studs. The best option is to resurface the manifold face in a milling machine as a new manifold will inevitably warp again sooner or later. By resurfacing the manifold it is highly unlikely to ever warp again. There is also a kit to convert the existing studs to headier diameter studs but on a V8 I'd reckon it's not possible with the heads insitu. Tuning of any type increases the manifold temperature and increases the likelihood of warping.

I can speak on the subject from experience, albeit a TD5, I've been there and done that, sheared studs and all.

Cast iron castings are unstable and the heating and cooling releases stresses which results in warping.

There is an article and fix in LR Monthly on the subject of warped manifolds.
 
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Old Apr 17, 2017 | 12:14 PM
  #5  
jamestfl's Avatar
Winching
Joined: Jan 2014
Posts: 741
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From: South Flatistan
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X2 on a ratcheting bolt / stud extractor.
 
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Old Apr 17, 2017 | 02:37 PM
  #6  
matt3502's Avatar
Winching
Joined: Sep 2010
Posts: 745
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From: Fairfield County, CT
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I just dealt with this and have an easier way!
Take the new stud to a hardware store and get two 8 grade nuts for the bolt. Spin both on to broken stud. Spray with a ton of PB blaster and let it sit overnight. Place a regular wrench in the nut closest to manifold and start to back bolt out. Outside nut will lock against inner nut, and bob's your Uncle, the stud will come out.
Did this about a month ago, no need for extractor which may not work and strip the threads off the stud.
 
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