Removing manifold bolts

Vacherie · Aug 12, 2008

I am preparing to remove the exhaust manifold bolts on my 140. I thought studs and brass nuts would be there but they are cap screws. To avoid breaking any off which is the best procedure to remove without breaking? Three are already loose.

Anonymous-0 · Aug 12, 2008

On a manifold like that I usually hit the head of the bolt with a brass punch pretty hard for about twenty hits. Then find a socket to fit since more than likely the bolt head is weathered and rusted anyway. Usually have to drive on a 6 point metric socket. If it doesn't want to come loose repeat the procedure. Whatever you do be patient and don't force it. As a last resort I have heated the manifold with a torch to a dull red glow. Just don't get it too hot.

Janicholson · Aug 12, 2008

I agree with JR.
It will be easiest if still connected to the head of the bolt, not twisted off. Be very patient. heating the bolt to cherry red, then letting it cool to cold will also break up the rust. JimN

Cub n M in OR · Aug 13, 2008

NOW. This may not be advisable, but it worked for me, when I was taking the manifold off of my M. After hitting them with penatrating oil for a few days, I hooked my impact wrench to the pressure regulator I use when I am spraying paint. I turned it down to like 30 lbs, and let it do its thing. Rattled a little, shook things loose. Turned the pressure up SLOOOWLY. 5 lbs at a time, rattled things some more, let it work for a while. Then finally, it shook em loose.
Like I said, may not be advisable, but it worked on the stubborn bolts I had.

Good Luck,

Ben

David Goode · Aug 13, 2008

I just removed the Manifold on My Super M. I thought it was rusted on really good but after soaking it for a week in WD40 it came loss when I took a breaker bar to it, I would recomend using a six-point socket.
-David Goode Coggon, IA

Red Mist · Aug 13, 2008

(quoted from post at 20:07:34 08/12/08) I am preparing to remove the exhaust manifold bolts on my 140. I thought studs and brass nuts would be there but they are cap screws. To avoid breaking any off which is the best procedure to remove without breaking? Three are already loose.

I have had good success with the technique jaNicholson (Jim) mentioned; heat cherry red, then let cool. Still..... take it easy. mike

Anonymous-0 · Aug 13, 2008

Just remember, if you heat up the bolts cherry red they harden every time you do that. They also get more brittle. So if you break one off it will be harder to drill out. Keep that in mind. Sometimes, it takes a combination of things in moderation.

Vacherie · Aug 16, 2008

Thanks for the input. I will be gentle but persistant.

Removing manifold bolts

Vacherie

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Anonymous-0

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Janicholson

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Cub n M in OR

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David Goode

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Red Mist

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Anonymous-0

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Vacherie

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