Just bought a 1995 GMC C1500

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Honky Kong jr

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I was looking at the exhaust manifolds, and I don't see any gaskets at all, on either side. Driver side manifold has a missing or broken bolt. I stuck a screwdriver in there, and I think it broke off in the head. Wtf! If it is, I'm guessing it's gonna be a PITA!!! getting it out.
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Do your self a favor before you pull the manifold get yourself a set of transfer punches from HF. Center punch the broken stud then pull the manifold. Transfer punches are a good investment.
 

HotRodPC

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Anybody know what gaskets these manifolds take, round, or square port?

IIRC, square and round only matter on Big Blocks.

Just so you know ahead of time, you're most likely to need a manifold spreader to get those back on. Maybe off too. Cuz of the heat, they close up and it's a real bitch to get the bolt holes to line up. So the spreader will spreads the ends open so the bolt holes line up. One the bolts are snugged, you can take the tool out.
 

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I was looking at the exhaust manifolds, and I don't see any gaskets at all, on either side. Driver side manifold has a missing or broken bolt. I stuck a screwdriver in there, and I think it broke off in the head. Wtf! If it is, I'm guessing it's gonna be a PITA!!! getting it out.
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That is what it sounded like to me, but I thought that would have been obvious. It sounded like real bad exhaust leaks or maybe even a cracked manifold. Hopefully it just is missing exhaust manifold gaskets.
 

Honky Kong jr

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IIRC, square and round only matter on Big Blocks.

Just so you know ahead of time, you're most likely to need a manifold spreader to get those back on. Maybe off too. Cuz of the heat, they close up and it's a real bitch to get the bolt holes to line up. So the spreader will spreads the ends open so the bolt holes line up. One the bolts are snugged, you can take the tool out.

Put the manifolds in the oven for a little while get some heat in then not a whole lot and also take them off warm.
 

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Do they make headers that fit, the existing OEM Y piping?
 

VAL

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And the plot thickens! Was crawling around under the truck, and found this.
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Rear passenger upper shock mount, broke clean off.
 

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And you'll probably find some more surprises too. You got a killer deal on the truck so you've got to expect a few things wrong. Nothing that can be fixed though.
 

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Today I plan on taking the manifolds off the heads. I'm kinda worried about breaking another or a few more bolts in the process. What's the procedure on preventing that possibility?
 

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Biggest Tip, TAKE YOUR TIME, TAKE YOUR TIME !!! Warm up the truck so they have a little heat on them. Of course be careful not to touch the manifolds and burn yourself. The biggest hurdle is going to get them to crack loose and not break off. If you can get them loose then you can probably get them all the way out without breaking them off. You can even try to tighten a little more and they might crack that way, then back them off a little bit, like maybe 1/4 to 1/2 turn, then go back to tighten, then back up 1/2 to full turn, if it feels OK, back it off some more. When you start to fee them tighten up again, go forward again like you're tightening them, about a full turn, then go back a few more turns. If you play that back and forth game you'll get them out without breaking them. Just be to sure to at least get them all to crack loose while you have the engine warmed up. Just do one side first. Then warm it up again and do the other side. Just got to work them bolts and make them YOUR BITCH, otherwise, they're going to be your bitch. A real big bitch if you break them off in the head.
 

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I found the exhaust leak!
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NOT surprised. See I told you the video just sounded rattly to me like maybe a broken exhaust manifold. I guess I did hear it right after all.

Oh and I said you're likely to find some more surprises.
 

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That's exactly how the manifold on my TBI 305 broke. Took me YEARS to track it down. Manifold gaskets, donut gaskets, etc. I tried everything. Finally, one time I took it off, the heat shield had rusted enough, and the whole dang thing fell apart. Turns out the heat shield had been the only thing holding it all together for quite some time!
 

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NOT surprised. See I told you the video just sounded rattly to me like maybe a broken exhaust manifold. I guess I did hear it right after all.

Oh and I said you're likely to find some more surprises.

Yup, got to give you props on that! I got the passenger side off without breaking any bolts. I loosened the driver side bolts, but it looks like I'm going to have to remove the ps pump to get the fist two out.
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VAL

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That's exactly how the manifold on my TBI 305 broke. Took me YEARS to track it down. Manifold gaskets, donut gaskets, etc. I tried everything. Finally, one time I took it off, the heat shield had rusted enough, and the whole dang thing fell apart. Turns out the heat shield had been the only thing holding it all together for quite some time!

Yup, that is some covert **** indeed.
 

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Yup, got to give you props on that! I got the passenger side off without breaking any bolts. I loosened the driver side bolts, but it looks like I'm going to have to remove the ps pump to get the fist two out.
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Can you not just take the bracket off the back of it or is it all 1 pc?
 

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