Inlet manifold bolts rounded - any ideas ow to remove?

So I decided to replace my. rocker cover gasket after i noticed a slight weep and now I have a problem with 2 bolts on my inlet manifold.

Do I have any options here other than drilling them out?

I snapped my allen key head off on the first bolt and the 2nd is totally rounded.

Is there any tool or device o can use to grip these bolts to get a turn on them?

So far this is the route im taking

https://www.youtube.com/watch?v=Xob4hNPbypw

I'd say drilling is the only way but use decent cobalt drills.
Those cap heads are as tough as f………..

yeah will do my fear is going through the manifold if i go heavy with the drill.it dosent help having an allen key head stuck inside the bolt either!



on a related note where can i pick up a set of abf manifold bolts? N0199035

My preferred technique is to use a Dremel to grind 2 flats onto the bolt head, then use an adjustable spanner to undo it. I suspect you won't get an adjustable in there though, so it might be better to try get a decent mole grip on there, or try grind a hexagon then hammer on a normal socket.

Failing that, next try would be to grind a slot onto the bolt hole then use a large screwdriver bit, but this tends to be weaker.

If that doesn't work then use the Dremel to grind the entire bolt head off. The remaining part of the bolt will come out much more easily once the tension is off it.

Sometimes its possible to get a DECENT mole grip onto a bolt head and grip it enough to turn it, but it will probably just chew it up if its stuck. Another way is to sacrifice a Torx, security Torx or XYZ spline bit, and hammer it into the rounded socket then turn it.

Yea im gonna try a long nose vice grip tomorrow. Failing that ill give the small disk a go then drill action..

Left-handed Drill bits and a reversible drill.
Grinding a slot is another…
Hammering in a torx bit works too sometimes.

Spray some plusgas (WD40 is rubbish) around the bolt and let it soak in overnight may also help, I had to hammer in a torx bit into mine to remove it as it was rounded off.

http://www.ebay.co.uk/itm/Plus-Gas-Releasing-Fluid-Aero-400ml-Dismantiling-Lubricant-/231308423514?hash=item35db0e715a:g:9eIAAOSwQItT7eSA
 

SUCCESS!

I managed to get the manifold off, I used a small cutting disk to cut a slot and then using a small chisel i was able to crack the 2 remaining bolts.

Thanks for all the advice its much appricated.

Blob of copper grease on the threads of the new bolts will stop this happening again as the person before you must of had problems undoing the bolts and rounded them off, copper grease won't melt like normal grease.

As Mark above said.
The best stuff for this is the good old fashioned Cooper Slip! 👍

I've used it for the past 40 years. 😉