how to remove a crankshaft bolt rounded off

This is the Forum for all your Citroen Technical Questions, Problems or Advice.
User avatar
jsp
Posts: 330
Joined: 04 Dec 2014, 02:05
x 12

how to remove a crankshaft bolt rounded off

Unread post by jsp »

How to remove a crankshaft bolt that is rounded off?

I am repairing another TU engine on an engine stand but, the crankshaft bolt wont come off.
Peter.N.
Moderating Team
Posts: 11778
Joined: 02 Apr 2005, 16:11
x 1240

Re: how to remove a crankshaft bolt rounded off

Unread post by Peter.N. »

If you can find a socket that is slightly smaller than the bolt and hammer it on, that would be the easiest way, if that won't shift it weld a large nut onto the head of the bolt, not only will that give you more purchase but the heat will expand the bolt, hopefully loosening it.

Peter
User avatar
Paul-R
Moderating Team
Posts: 9228
Joined: 07 May 2009, 16:24
x 1919

Re: how to remove a crankshaft bolt rounded off

Unread post by Paul-R »

If the socket is bi-hex (has 12 points) then a single hex socket might do the trick. preferably one that is a fraction smaller than the correct size - maybe an imperial of NF socket in place of the prescribed metric one.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson
User avatar
DHallworth
(Donor 2025)
Posts: 2431
Joined: 20 Nov 2005, 17:05
x 163

Re: how to remove a crankshaft bolt rounded off

Unread post by DHallworth »

The other option is a cold steel chisel and a hammer, hold it level with the bolt to mark it, then once it's cut a small groove in the edge, turn the chisel so it's almost at 90 degrees to the bolt and beat it with a lump hammer in the direction you'd be undoing the bolt in.

That method has saved me a load of times!

David.
'98 Xantia Activa V6 :-D
'00 XM V6 Exclusive
'09 C5 2.7 HDi Exclusive
‘10 C5 3.0 HDi Exclusive
'12 C6 3.0 HDi Exclusive
'15 C4 BlueHDi Feel
User avatar
Sloppysod
Moderating Team
Posts: 1488
Joined: 23 May 2015, 23:35
x 385

Re: how to remove a crankshaft bolt rounded off

Unread post by Sloppysod »

Question, I do not know this engine, but is this a lefthand threaded bolt? Are you trying to move it the right way?
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

"Some cause happiness wherever they go, others whenever they go"Oscar Wilde (1854-1900)