Oil Filter Cover Lower Bolt Sheared - 2001 4PT
 

Grrrrrr. Being conscious of the fragile nature of the bolting arrangement on the oil filter cover, I decided to use a torque wrench when refitting the oil filter cover. In the past I have tightened the bolts manually and have relied on 'feel' with no problems encountered. I tightened the bolts sequentially until to just over finger tight and then applied the torque wrench using the values in the handbook. The top two long bolts were fine and the wrench 'clicked' as expected. The bottom one sheared before the 'click'.
The bolt has sheared at the point that the thread begins.
Initially I thought that this was a better situation than the thread stripping but then I wondered how I was going to get at the residue of the bolt.
Can a wise owl please tell me if the lower bolt threads into a blind hole or would I be able to get at the back of it if I was to remove the crankcase cover. Alternatively, I guess if the cover was removed I might be able to work the broken end out.
I would be grateful for advice.
Thanks in anticipation.

The hole does go through on some but they really aren't supposed to. About all that can be done is drill it out and use a good quality easy out. It shouldn't be that tight in the hole if the head is gone and it wasn't bottomed out on the end of the threads(which is why some have the hole all the way through. Left handed drill works just as good often grabbing and turning the reminent of the bolt out in the process .

Good advice above. Hope you get it sorted.


Will you bin the numbered wrench or get it calibrated? While I feel your pain, I do wonder why people continue to trust a massive bar they bought for a few quid and has sat in a drawer for months if not years. If the thermometer in the garage said minus 40 on a sunny day they wouldn't give up and go indoors, yet everyone (I did it myself years ago) still pulls on that numbered bar until the thread goes.


Andy

Well i dont know, torque wrench or not if you always have done it for hand you should be able to feel that something is wrong then these bolts only need 10nm. Its almost no power on any wrench, to pull the threads you must have done alot more or they have been wrong tighten alot of times and just this time it was over.

He actually broke the bolt itself not stripped the threads which may be more a case of bolt fatigue over repeated tightening/loosening cycles. Most likely over torqued repeatedly but I don't think as much as one would think, unless the threads are bottomed out at the end of the blind hole. Either way I for one have never skimped on a tool like a torque wrench and go with certified brands to eliminate the % of variations in true readings, "feel" can/should never be ignored no matter what is used.

I have checked torque wrenches in a professional capacity. The bar with numbers on sat at the bottom of a tool box is not a torque wrench. Either callibrate it or bin it.

Andy

Ok, cant brag about beeing very good understanding all you people write here, if its only bolt your lucky. You could try with a new bolt in, use special superglue/gel on the end and hope it connect to the rest inside, i dont think the remaining bolt sit very hard. Or maybe the bolt broke because it was stuck inside, then you have a serious problem. Never experience a bolt like that snap of with 10nm torque, bet it can handle 30nm with not snapping.

Thanks for your interest. My torque wrench is stowed in its protective case which in turn is stored in a drawer. It is a middle of the range tool in terms of price and has always appeared to have done its job satisfactorily. At what stage do you decide that a tool is not performing well? I guess in circumstances similar to mine when a bolt snaps or a thread strips. But, why only 1 of 3? I think the answer lies somewhere between inaccurate torque wrench and weakened bolt.
Anyway, replacement bolt, o ring and gasket ordered and next job is to dismantle cover and attempt to remove residue of broken bolt.
In future when torque limits are so small I will rely on feel when tightening.

Removed the crankcase cover today to discover that the hole goes all the way through. Hoorah! There was insufficient of the end of the bolt poking through to grip so drilled a hole in the end and with the assistance of, initially, a broken drill and subsequently mole grips I was able to remove the broken piece of bolt by just continuing to turn it all the way through.
Just awaiting delivery of new bolt, gasket and o ring.
Only hiccup was that as I removed the clutch actuating arm I realised I had not marked its exact pre-removal position.
I am just so pleased it was that bolt that snapped and not one of the others that go into the crankcase itself.

Good for you:thumbup1: