Viewing: Removing rusted manifold bolts

***waynne*** · 26-01-2010, 10:38 AM

Any suggestions on how to remove an exhaust manifold when the nuts have rusted onto the bolts? (I'm helping out a mate and he's kind of messed things up!)

The magic of WD40 is just not working and neither does hitting it with a hammer. Any tips would be grately appreciated.

(The actual nut shape has also become rounded so it is actually pretty hard to even get a decent purchase on it because someone was using a plumber wrench on it!)

**prevtec** · 26-01-2010, 10:44 AM

ifyou have acsses to a welder, it helps,

weld new bolts to the rusted 1s ( CLEANED FIRST OBVIOUSLY)
it should hold to get it loose, ive seen it many times

sometimes just heating them will work, but because yours are rounded, thats my advise

**pgarner** · 26-01-2010, 05:01 PM

gas torch helps alot
wd40 left to soak in for a couple of days - keep spraying every so often

and if you can get a good grip - mole grips perhaps - try tightening the bolt slightly to break the rust seal

***waynne*** · 26-01-2010, 05:21 PM

It's as if the rust has welded the nut to the thread completely. I fear that a drill may be the only answer but any suggestions are gratefully recived.

**pgarner** · 26-01-2010, 05:28 PM

lots of heat them.
or soak in WD40 and hit with a hammer.
can you hammer a smaller ring spanner over the top ? if so get it on and try hitting that gentle with the alloy ajuster - only really advisable if you think your going to be drilling it out anyway

***waynne*** · 26-01-2010, 05:29 PM

Not a bad suggestion. "If in doubt give it a clout"! We'll give that a go.

**MasterAuron** · 26-01-2010, 06:55 PM

Problem is WD40 usually does sweet FA despite people swearing by it. Think about it, if the bolt is rusted tight how it the WD40 going to penetrate.

Welding on another nut is a great technique tbh but if you don't have access to a welder....What I do is use a dremmel or grinder to grind each edge of the nut down slightly to the next size (and back into shape a bit more) and then hammer the next size ratchet down onto it (if it was 15mm, use 14mm etc etc) and voila. Never failed me yet. Heating the bolt first will also help no end.

**Country Bumpkin** · 26-01-2010, 08:41 PM

Can you get a drill bit to the nut ? If a nut is drilled on the sidewall it will split with impact from a decent chisel. Remember to use a centre punch to prevent the drill bit from veering off line.

**prevtec** · 26-01-2010, 10:19 PM

all the technices mentioned are good, but people, this is a manifold were on about, you know the thing connected to the engine block

chisels and drills are a bit too dodgy, in my eyes anyway
bring the car to a welders yard, weld new bolts on, then drive away, when you want to take it off is your own time

ps, a welder will do the job for pennies, ans its the safer rd to go down

**dpsubaru** · 30-01-2010, 02:38 PM

as suggested above, usually try to tap a smaller size socket on the end of it and take it from their. often they snap off in any case so have to be replaced (or perhaps this is just the way i am undoing them).

**prevtec** · 30-01-2010, 11:59 PM

manifold bolts are usally srewed into the engine block, if they snap off, well just say i didnt warn you

***herb*** · 31-01-2010, 12:33 AM

when ive had manifold bolts snap i have found them easy to get out by using mole grips! but this was on cars with the manifold at the front of the engine (easy access) suppose this isnt the case with the manifold at the rear??

**speedy** · 11-02-2010, 09:52 AM

use plenty of heat and a braker bar about 4 foot long sould do it.

**macjessop** · 11-02-2010, 06:37 PM

I use a sharp chisel on the flat, or what remains of the flat, to split and open up the nut. It usually comes off with pliers if you do it correctly and it saves the stud thread

**claymore** · 11-02-2010, 07:58 PM

Invest in a nut splitter, got me out of many a pickle.

**indiaman** · 28-02-2010, 05:11 PM

You could use Dremel to grind off one side of the nut, this always works for me

**wolfmankurd** · 23-04-2010, 01:51 AM

vinagear eat rust. maybe that'll loosen it up

**indiaman** · 23-04-2010, 06:08 AM

Quote:

Originally Posted by claymore

Invest in a nut splitter, got me out of many a pickle.

Claymore has the right idea, I have used a nut splitter when all else failed to budge a rusted nut

**petescustompipes** · 29-04-2010, 11:43 PM

invest in a extactor socket. they specialy designed for removing rung nuts and bolt heads. they have four taperd spiral shaped cutting edges inside the socket to grip into the nut the more you pull it the more the edges grip into the nut. get a gud long pull bar, quick blast o the gas and straight on with the extractor and the job is done.