Suspected exhaust leak.

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84 Shorty

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I’ve had a ticking noise that has gotten worse. I suspect it’s the exhaust, I started at the front of the engine and worked back. I was going along checking the manifold bolts for tightness and found my back passenger side rear bolt was missing.

I looked at it further and found that there isn’t a hole in the block to even receive a bolt. My guess is they are 305 exhaust manifolds. Can these seal up right on a 350?

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bucket

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Some manifolds had a longer bolt spacing on one end. But many later heads include that extra bolt hole. What heads are you running?
 

84 Shorty

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Stock heads that’s all I know.
Some manifolds had a longer bolt spacing on one end. But many later heads include that extra bolt hole. What heads are you running?
 

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Something not stock. Might have to take valve cover off and check the numbers on the head. Or just get different exhaust manifold
 

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I bet the manifolds are from a Buick 350.
 

bucket

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I bet the manifolds are from a Buick 350.

Those would be very different than Chevy small block manifolds.

Some smog era manifolds have the end bolt in a different location. Their use requires heads with a "7th bolt hole" for the exhaust manifold.
 

84 Shorty

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I’m just going to go with some hookers or Hedmans.
 
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CSFJ

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It's a 305 manifold on a 350 head. I've run across it before. I've also seen a very backwoods, but functional bracket bolted to the back of that head holding a bolt that could be turned in to clamp that rear hole of the manifold against the head.
 

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So I found the exhaust leak while the engine was running I ran my hand around feeling for air. The leak is coming from the donut, the seal is in bad shape. My question is how and the hell do you get that top bolt off without having to cut the exhaust off to get to it? I got the bottom two bolts off. May be hard to tell in the picture.

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Blue Ox

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Wrench, universal, swivel socket?
 

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What do you mean by "the top bolt"? Those should be studs threaded into the manifold. There is no bolt head on top. Furthermore, they managed to tighten the nut on the stud originally, so it must not be completely blocked. If all else fails, torch the nut, and install a new stud. But you'll still need to figure out how to tighten it.
 

Blue Ox

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Socket won’t even fit over because of the exhaust pipe. No room to turn a wrench because of the frame.

They make curved wrenches too. Or you may be able to make your own out of a cheapo wrench with a torch.

Just sayin' there has to be a way. I've always managed to do mine with ordinary tools. But sometimes you have to get creative.
 

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