Club G40 Forum

Technical => Engine and Transmission => Topic started by: hayesey on April 20, 2009, 08:51:47 PM

Title: drilling out a snapped rocker cover bolt end
Post by: hayesey on April 20, 2009, 08:51:47 PM
Like a tool I got carried away tightening the centre rocker cover bolt tonight and snapped it.  The snapped end is stuck in the thread in the cam bearing cap.  What's the best solution?  Is it possible to get a very small easy-out and remove it or am I best finding a local machine shop who can sort it out for me?
Title: Re: drilling out a snapped rocker cover bolt end
Post by: scotsjohn on April 20, 2009, 09:22:55 PM
Seen it, done it and the easy out works OK. It's difficult finding the centre so start with small pilot drill first then work your way up. It takes no effort at all as you now know to snap the damn things, but the stub comes out easy for that reason. Bolts hard to get now, best of luck.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: Dan on April 20, 2009, 09:30:59 PM
I think they might be thread inserted as standard. Have you got a pic of it ?
Title: Re: drilling out a snapped rocker cover bolt end
Post by: hayesey on April 20, 2009, 09:54:39 PM
I've already got a spare bolt, I use mk4 bolts since I have a mk4 rocker cover on mine.  Yeah the snapped bit is loose you can move it around, tried to grab it with some smaller side cutters and managed to get it to rotate about half a turn but now I think it's just going to knacker the bearing cap if I keep trying that way.

Title: Re: drilling out a snapped rocker cover bolt end
Post by: Dan on April 20, 2009, 09:57:28 PM
If you can move it, just soak it in penetrating fluid. Try and pick it to turn it out when it's soaked a bit.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: Glader Poison on April 21, 2009, 12:50:08 PM
Have you tried to use a magnet?
Title: Re: drilling out a snapped rocker cover bolt end
Post by: hayesey on April 21, 2009, 01:15:49 PM
it's not loose enough for a magnet.  I managed to turn it a little bit using some long nose pliers and a pointy screwdriver but it wont go any further now, can't get a good enough grip on it.  I've ordered a set of easy-outs now which should arrive tomorrow. I also have a spare k03 turbo with a sheared manifold bolt stuck in it so I can use one of the easy-outs on that too!
Title: Re: drilling out a snapped rocker cover bolt end
Post by: Robin on April 21, 2009, 05:11:16 PM
TOOL
Title: Re: drilling out a snapped rocker cover bolt end
Post by: NeilG40 on April 21, 2009, 05:56:58 PM
I did the same thing myself, I took it to an engine builder in the village and they got it out for me.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: Dan on April 21, 2009, 06:39:31 PM
Them easy outs aren't great as they bulge the screw out. If it's not tight then it might be ok. I'm sure I used a facom srew extractor set once which was good for light duty screws.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: SuperMario on April 21, 2009, 07:46:55 PM
Easy out should work a treat as said aslong as you use a small drill bit 1st, just dont snap the easy out or you will be looking for a new bearing cap!
Title: Re: drilling out a snapped rocker cover bolt end
Post by: NeilG40 on April 21, 2009, 08:14:20 PM
Quote from: Musto on April 21, 2009, 07:46:55 PM
Easy out should work a treat as said aslong as you use a small drill bit 1st, just dont snap the easy out or you will be looking for a new bearing cap!

Or in other words a new head as the caps are machined to the individual head.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: scotsjohn on April 21, 2009, 09:12:08 PM
Have someone standing by with the old Henry to suck up the swarf when you're drilling it; rather like your Dental Assistant. Like a twat I didn't and spent an age searching about with tweezers and a magnifying glass.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: jez1272gt on April 21, 2009, 11:02:17 PM
Quote from: scotsjohn on April 21, 2009, 09:12:08 PM
Have someone standing by with the old Henry to suck up the swarf when you're drilling it; rather like your Dental Assistant. Like a twat I didn't and spent an age searching about with tweezers and a magnifying glass.

haha that sounds like my ideal sunday afternoon. might give it a go sometime!  :)
Title: Re: drilling out a snapped rocker cover bolt end
Post by: hayesey on April 22, 2009, 09:27:48 AM
Quote from: scotsjohn on April 21, 2009, 09:12:08 PM
Have someone standing by with the old Henry to suck up the swarf when you're drilling it; rather like your Dental Assistant. Like a twat I didn't and spent an age searching about with tweezers and a magnifying glass.

well I've got the cap removed from the engine so swarf wont be an issue.

I'll give the easy out a try tonight.
Title: Re: drilling out a snapped rocker cover bolt end
Post by: DaBigGinger on April 24, 2009, 09:03:13 PM
Be careful not to snap the easy out! I've done that before - being toughened steel, they are a git to get out if they snap!
Title: Re: drilling out a snapped rocker cover bolt end
Post by: hayesey on April 24, 2009, 09:18:23 PM
I've got this sorted now, drilled the snapped bit out a bit and then tapped in a star shaped screw driver bit and undid it.  Panic over!  8)

I did buy some easy-outs but there were bloody useless!