Rounded off bolt....what to do next?

[mjtray]

Right,

Just went to change the oil on my recently acquired W124 300D and found that the sump pan bolt had the consistency of butter and rounded off...what do I do next

Somebody has suggested mole grips and once its shifted making sure that the bolt is replaced (obviously).

Is this the best way to get this bolt undone?....the thought of having to pay ££'s to get it tapped out does not fill me with joy.

HELP!!!!

 

[LNM]

Ayup

Have you tried the Mole grips? Seriously, its the first thing I'd do.

 

[teky]

failing that a nice pipe wrench will do it and when you fit a new bolt dont forget the copper seal

 

[Spike]

... and if you get *really* stuck, find an old manky spanner and spot weld it onto the rounded off bolt

 

[paulcallender]

Saw a slot into the bolt and then use an impact driver to free it off?

 

[Hal Fisher]

Big Vise grips. Clamp down tight and turn.

Hal

 

[TimN]

Bang on a size smaller socket. Don't use a six sided socket but one of the cheaper types that hold the bolt on the apex rather than the side. Use an imperial if that cuts nicely into the bolt head. I also find the star bolt sockets (For want of a better discription), the type used on some cylinder head bolts pretty good for this application.

In the past I have welded another clean nut onto a head of a bolt by spotting through the centre of the nut.

Why not just remove the dip stick. Get yourself a hand pump and stick the suction pipe down the dip stick hole and forget about removing the bolt, jacking up the car and getting generally unnecessarily uncomfortable and dirty and get the job done much quicker without spilling oil etc.

 

[mjtray]

By sucking up the oil out of the dip stick tube, don't you run the risk of leaving a load of crud at the bottom of the sump, or have I been reading too many horror stories?

 

[190]

I agree with Tim N hammer a smaller socket onto the sump plug

 

[pluggers]

Might be a bit dodgy hitting a small socket over the nut as it could cause the sump to crack

Id be tempted to use grips/stilsons or some kind of self tightning spanner for the job.

 

[landover]

Dont use a hammer on your sump or vice grips .You can take it off with a TURBO socket .These sockets grip as you turn .Same idea as an easy out Snap on tools do them . Even borrow one from local garage.

 

[Myros]

tough nut

MJTray, time for me to return a favour. You could get a chisel and gently hammer it in the nut anti-clockwise and try and turn it that way as well. You can do this 3 or 4 times before you need a new nut, but I recommend it as emergency kind of thing. I'd be dead careful though, as it's a vital bit of the car to be hacking about with. You could also file new flats on the nut and try the mole grip/socket routine. Give it a good dose of wd40 or penetrating oil before you get to grips with it.
The C280 still starts like a dream, but I had bit of a do with oil level last week.
Good luck, Myros