200 TDI Crankshaft pulley bolt sheared off

Guys,

I'm attempting to change the timing belt on a 200 TDI. The crankshaft pulley bolt needs to be removed, we know its held on tight, and we know to undo it it needs to be turned clockwise, so; attached the tool to the pulley which was wedged to keep it still, used a 30mm socket on a 3/4 inch breaker bar and tube to extend the bar. Then me and Rob gave it some muscle and guess what? it started to move, so we continued for a couple of turns.....then disaster!! The bolt has sheared off. I assume the next step is to drill the remainder of the bolt out carefully, by using progressively larger drills and carefully clean the threads? Anybody got any experience of successfully doing this or has other better ideas? Any assistance gratefully received.

Thanks. Nick

Im sure when i done my cambelt the pully bolt was anticlockwise to undo it! anyway im not even sure a easy out would do it so maybe the best way would be to weld a big nut onto the remaining bolt, you may have to replace the crankshaft seal tho depending on how hot it gets. mikey

Well if you are lucky with the pulley off here may be enough thread protruding to get some grips on or weld as Mike suggests.
By the way the bolt is a std bolt and undoes anti-clockwise!


Lynall

It's the viscous fan nut that's LH thread not the crankshaft pulley bolt.

Guys,

Many thanks for your replies. The manual implies that the nut undoes by raising the breaker bar (clockwise), however this is wrong as you've pointed out. Thanks. There wasn't enough of the bolt remaining to weld to, so a piece of solid bar about 3 inches long was drilled in the centre with a 6mm hole, then one end of the bar was recessed to about 1 inch so that it would fit tightly over the crankshaft. Both operations were done on a lathe. A 6mm was then drilled into the torn bolt, using the device to guide the drill to a depth of 50mm (past the end of the torn bolt). The guide was then drilled out to 10.5mm, again on a lathe. The 6mm hole was drilled out to 10.5mm using the device as a guide, the hole was drilled to a depth of 50mm. A 12mm tap was then used to thread the hole, the idea being to use an M12 bolt as a pulley bolt. The tap got about 15mm into the hole when the torn bolt started to move. The torn bolt was then turned out using the tap and a very small stilson on the now protruding shoulder of the torn bolt. RESULT!!

Thanks for all our replies, much appreciated.

Nick