Stubborn crankshaft pulley bolt - any tips?

They're a bastard, heating them up helps if you've got a welder. If the

12V impact wrench manages it I'd be surprised, Breaker bar against a wood block with a coupe of inches throws got more chance, but then when it is loose there's nothing to stop it slipping.

Something I should've possibly added - whilst my impact wrench supposedly g ives up to 350Nm torque it's just dawned on me that I've mainly been using a 4" extension bar (supposedly an impact one) with it given that even with the engine lowered to the extremity of the other mounts the bodywork preven ts the tool sitting well on the bolt without it. Perhaps though the bar cou ld be reducing the torque through it twisting and I should endeavour to do without?

That'll help.

Are you talking about the 'starter' method?

Yes, if you let the bar swing it hit's a lot harder.

DO NOT spin it on the starter to try to undo it, you will wreck the valves at least.

Lock the flywheel (in the right position) using either a real flywheel locking tool or a prybar in the teeth of the flywheel and undo the nut with a long breaker bar.

It was frustration setting in I think. I knew once I'd done it I should wal k away to think things through! Indeed, I've just read a forum thread docum enting someone using the timing pin to turn against and it bending inside t he engine block so I'm going to stick by the book I think! They still didn' t manage to get the bolt undone so ended up grinding it off. Amazingly it a ll ended well.

Laser do a flywheel locking tool (4275) which is apparently 'for Fords' but I don't know if it'll definitely cover this specific engine. It's £25 to o, which if it will then fine but if not...

How dodgy is the use of a prybar? Of course you can't say for this particul ar circumstance but is it something approaching 'accepted common practice'?

It is the way I have undone many, many engines without any ill effects.

And when you fail to move it with the 24" breaker bar. Put a 1.8m length of thick wall steel pipe over it. My "extension" is a tube from the frame of an old car port.

Though I have sheared 3/8 drive extension bars and put a permanent twist in a short 1/2" extension.

I found an old piece of scaffolding pole buried in my garden, over twenty years ago. It's still one of the most useful things I have.

I have a Maplin one which runs off the car battery. Did the SD1 crank pulley bolt no problem, and that's pretty tight. Think it says up to 250 ft.lb.

Yup. Any extension dramatically reduces the impact.

The Fiesta one's an unkeyed pulley so it's angle tightened.

I've got a 5' scaffold extension to slip over my 24" breaker and have order ed a flywheel locking tool (Laser 3575) so when that arrives I'll give it a go.

I tried putting it in gear and getting my wife to stomp on the brakes but t here still seems to be too much 'slack' in the drivetrain to counter my tur ning - certainly for short sharp shocks which I figure is what's required. I'm hoping the flywheel tool will lock things solid?

Here's the bugger:

...and the new bolt (choice of two depending on length of the existing one) :

I'm wondering if, if all else fails, I could/should cut the 'washer' off th e existing bolt with a Dremel cutting disc so as to reduce the grip it has on the pulley? That or perhaps some other destructive strategy?

Does the panel think that if the bolt head shears off then I'll still be ab le to pull the shank out due to it no longer being loaded?

This isn't going to beat me. If I have too I'll take the bl00dy engine out.

This one is (don't laugh - it's been great until now!) an RAC branded one f rom Tesco:

It claims 'up to 350Nm'.

Thinking optimistically for when the bolt finally does come out, do you thi nk the impact wrench might suffice to tighten the new one up? It requires ( off the top of my head) 40Nm + 90° so I'm assuming that having used a tor que wrench for stage 1 I can attempt the 90° extra twist with the uncontr olled impact wrench having marked the bolt (and locking the flywheel - I do n't trust the locking pin I've got).

If it's that subborn then drill down the centre of it.

The locking pin is fine for doing up the bolt, but useless for undoing it. A breaker bar is the way to do it up the right amount and use a new bolt.

Is there not the danger that I might knacker the thread of the crank?

I've never drilled a bolt out before so it'd be uncharted territory for me. My drill bits seem to be made of cheese too so would need to pick up one. I've cut plenty of nuts/bolts off though hence me leaning towards that meth od given I've got some confidence in that regard. If I somehow go too far a t least I'll only bite into the pulley which can be replaced easily enough.

Does that make a difference when undoing? You don't get many things on a car tighter than 250 lb.ft