Stripped nut on exhaust flange

rowan194 · 08-09-2011, 08:02 PM

Any ideas on how to get this thing off? Both a driver and ring spanner slip. (Haven't tried a normal spanner - that would be worse right?)

I've sprayed some penetrating lube on it and will try again tomorrow when the exhaust is stone cold (it was still lukewarm) but I'm worried the damage is already done.

Guess I need something that can grab the flat parts, rather than the corners...

Funny thing is that it was hard to do up properly (tight) when I replaced my welch plugs a few weeks ago, because it's in quite a fiddly location, so what's made it seize up since?

Thanks for any tips.

falconhell74 · 08-09-2011, 08:08 PM

Try a single hex socket , you may need to hammer it on as you have burred the nut but it should get it off for you.

JC · 08-09-2011, 08:17 PM

Or go and buy a set or Irwin Tools rounded nut thingos - bunnings sell them in a set to suit most sized nuts.

rowan194 · 08-09-2011, 08:32 PM

Quote:

Originally Posted by falconhell74

Try a single hex socket , you may need to hammer it on as you have burred the nut but it should get it off for you.

Cheers, should have thought of that myself, considering how much of a snug fit they are. I'll give it a go tomorrow. Hopefully there's enough clearance so the socket doesn't foul on the bolt end. The other nut is also halfway to being rounded, but I left that one alone as soon as I realised what was happening.

I have no idea where to find replacement nuts... buy them from Ford? I was at Bayford only a few hours ago.

falconhell74 · 08-09-2011, 09:04 PM

once you have the old one off take it to a bolt shop -coventry fastners etc or your local car parts place

Day-mow · 09-09-2011, 12:16 AM

super crap. and make sure you get hightensile ones. and you wont have the issue again

you could just angle grind it off?

mongrelEF · 09-09-2011, 12:27 AM

Got room for vice grips?

TheSly1 · 09-09-2011, 09:14 AM

hammer a socket on over it, thats your best bet and will always work, the hardest part about that method sometimes is actually having room to be able to do that..

done it many times.. itll work like a charm and that nut isnt even that bad

rowan194 · 09-09-2011, 09:41 AM

I got a "true" hex socket over it but it just strips the socket.

I looked at the socket and I can see the edges of the hexagon are slightly rounded rather than perfectly straight, presumably to make it easier to get on and off. Guess I need to find a better quality one.

Getting pliers or vice grips in there won't be easy, it's pretty cramped. And it just started raining!

A normal open ended spanner won't work right, since it won't be able to lock over the nut on all sides?

I still don't understand why it's seized when I only did it up a couple of weeks ago...

Waiting once more for my wife to get home so I can borrow her car...

crakrz · 09-09-2011, 09:47 AM

Make sure you use "Loctite Anti-seize" paste on the threads when it goes back together. Always lubricate threads on assembly of parts. And with areas with such high temps, you need this stuff.

-Craig

rowan194 · 09-09-2011, 10:09 AM

Quote:

Originally Posted by crakrz

Make sure you use "Loctite Anti-seize" paste on the threads when it goes back together. Always lubricate threads on assembly of parts. And with areas with such high temps, you need this stuff.

I was planning to lube the threads, but I'm having trouble finding anti-seize (supercheap gives me results for anti-freeze

). What extra function does anti-seize do that lube doesn't?

....

Back to the original question... would a flare wrench maybe be something to try? Looks like they're similar to an open end wrench, but have a hex shape and a better fit (hard contact against 5 sides). A "hex" spanner (completely closed, 6 sides) would be ideal but I don't know if those exist?

This was supposed to be a quick job: remove the manifold, replace the middle gasket, apply some gasket cement (exhaust temp rated) to faces and flange, replace the O2 sensor while it's out, reinstall the manifold.

I reckon · 09-09-2011, 10:18 AM

heat it up with an oxy then undo it.failing that soak it with inox or wd-40 overnight , or get a cheapo socket and put it half over the nut and tack weld it on. i have done this before and works a treat.

rowan194 · 09-09-2011, 10:48 AM

GOT IT! This time I really whacked the driver on, added an extra extension, and pushed hard upwards as I turned. It's amazing what a bit of a break to have a rant on here does.

Now it's off you can see that the damage is mainly to the upper part of the nut, so I probably just needed to get the driver on properly, and keep it on.

There is one slight problem... the nuts are still stuck fast, and last time I disconnected the flange just the nuts came off, not the whole bolt too.

I guess this arrangement is so there's some room for adjustment rather than the bolt just stopping at a specific point. Does anyone know what these double ended bolts are called? I don't think I'm going to be able to get the nuts off without damaging them, so it's probably better just to replace everything.

mac_man_luke · 09-09-2011, 11:31 AM

they would be "studs"

david lee · 09-09-2011, 02:14 PM

Quote:

Originally Posted by rowan194

Any ideas on how to get this thing off? Both a driver and ring spanner slip. (Haven't tried a normal spanner - that would be worse right?)

I've sprayed some penetrating lube on it and will try again tomorrow when the exhaust is stone cold (it was still lukewarm) but I'm worried the damage is already done.

Guess I need something that can grab the flat parts, rather than the corners...
Funny thing is that it was hard to do up properly (tight) when I replaced my welch plugs a few weeks ago, because it's in quite a fiddly location, so what's made it seize up since?

Thanks for any tips.

heat the nut with an oxy remove the nut from the stud and reuse the stud

mik · 09-09-2011, 02:31 PM

or carefully put a slot on each side of the nut with a dremel and try unscrewing it again, a couple of new nuts your away.

Day-mow · 09-09-2011, 02:32 PM

just buy new HT bolts and nuts?

rowan194 · 09-09-2011, 03:04 PM

Quote:

Originally Posted by Day-mow

just buy new HT bolts and nuts?

Yeah, ended up buying them from Bayford spares. They look a fair bit different new.

Also got some anti-seize spray.

Day-mow · 09-09-2011, 03:09 PM

Quote:

Originally Posted by rowan194

Yeah, ended up buying them from Bayford spares. They look a fair bit different new.

Also got some anti-seize spray.

thats the way. i think mine are like 15mm bolt heads. the thread on them is decently chunky and again i have them on and off a fair bit and i've never had issues with them seizing or anything like that

AMB · 09-09-2011, 09:48 PM

Who's saying heat them up with an oxy??? They're on the bloody exhaust manifold. Start the engine, get em hot. Works well on O2 sensor too.