Tricky nut

[NDNDNDND]

I was trying to get out this old fan switch at the weekend:



As you can see, it's so close to the exhaust manifold that it's impossible to get a socket or ring spanner to it. I could get an open wrench on to it (13/16") but the switch's already rounded off slightly - possibly from the PO's attempts to remove it - and I couldn't budge it before the spanner twisted off.

I was a bit stuck for how to get it off. Access is very limited as it's beneath the exhaust headers (manifold!). I couldn't find enough space to operate either normal or needle-nose mole grips down there.

So, I'm looking for some sort of wall-drive spanner. I've ordered a cheap 13/16' silverline spanner, and my plan is to cut a couple of points off the ring-end to form a sort of crowsfoot, but grind the cut end flat so I've space to get the spanner on to the switch. I'm a bit worried that enough force to turn the switch (if it even grips) will simply open up the ring where I've cut it.

So... after that rambling, any thoughts or advice?

Cheers!

[crossy67]

Take manifold off. Silverline "tools" are not the best, truth be told they're garbage so I wouldn't expect you to get anywhere with it. I had to change a temp sensor on a 1963 Rover 95 a few weeks back, I ended up with my big torque wrench and 6 point socket and a lot of force to undo it. Oh and a clean pair of pants after, scared it was going to snap off but it came out in the end.

[E-bmw]

Unfortunately, work servers won't let me see the pic, but agree with the above, if there is something in the way, remove it get better access & better tools on it.

What you are suggesting basically, is unlikely to work from you saying the A/F spanner already spins off the nut, it will likely open up the split ring spanner before moving it.

Have you tried slightly tightening before slackening?

Sometimes it works, nothing to lose otherwise.

Edited by E-bmw on Monday 21st March 15:29

[n3il123]

Obviously taking the manifold off to gain access is the best option, however would something like this work?

[guards red]

Never failed to remove a nut with these:

http://www.toolandfix.com/irwin-10504635-bolt-grip...

Don't need to be fully on the nut so may clear the manifold flange.

[paintman]

I wouldn't touch that with other than a hex or wall drive socket.
You might have to take other stuff off - or modify the socket - but rounding it off is going to make things worse.

[NDNDNDND]

crossy67 said:

Take manifold off. Silverline "tools" are not the best, truth be told they're garbage so I wouldn't expect you to get anywhere with it. I had to change a temp sensor on a 1963 Rover 95 a few weeks back, I ended up with my big torque wrench and 6 point socket and a lot of force to undo it. Oh and a clean pair of pants after, scared it was going to snap off but it came out in the end.

You know what? I think you're right. I ought to just pull the manifold and get at it properly. I think I'm a bit shy of removing it, as the last one I tried to remove was on my trusty old Micra and the bolts just sheared off. The Chevy manifold was installed by the PO only a couple of years ago and should come off relatively easily.

Anyone know how likely I am to get away with reusing the gasket?

[E-bmw]

100% likely if you you smear exhaust assembly paste on both sides when reassembling.

[crossy67]

I wouldn't even use exhaust paste, it will be fine so long as you have all the studs in place.

Not that I think it has but if it has a turbo you should never use exhaust paste as bits can break off and grenade your exhaust turbine.

[NDNDNDND]

crossy67 said:

I wouldn't even use exhaust paste, it will be fine so long as you have all the studs in place.

Not that I think it has but if it has a turbo you should never use exhaust paste as bits can break off and grenade your exhaust turbine.

Thanks for the reassurance - worst case scenario is I have to go and buy some gaskets for a tenner and do it again. No it doesn't have a turbo, but that's a good random fact to store away for future use