What Would Cause The Big End To Come Through The Block?

[nick9one1 2]

though my nice freshly painted block too

[welshpug 1,666]

looks like its lost a bolt/nut, either that or the crank has snapped on the big end pin.

 

taken it apart yet?

[Anthony 1,003]

Bigend bolt failure I'd guess

[Cameron 16]

OOOOOOO Nice work sir!

 

Ah, I remembered your last thread about the engine struggling to turn over and it set alarm bells ringing! Is this the engine?

My guess is you could have accidentally put the big-end cap on the wrong way around, since they have to go round a certain way it could have created a tight spot causing.. that!

[Alastairh 47]

Excellent picture.

 

Sorry

[nick9one1 2]

Excellent picture.

 

Sorry

 

thanks! quite dramatic I thought.

 

It is possible the big end went on the wrong way.. I did mark them all but I could have made a mistake.

 

It happened within minutes of the engine firing for the first time if that helps? Is it possible that the big end bearings being on the wrong way round would cause this? its the only other thing I can think of. I was pretty meticulous at getting all the torque settings correct.

[Cameron 16]

It could well be, was it tough to turn over by hand or did it only seem to struggle on the starter? What sort of revs did it happen at?

[Peetypug 5]

now i see why you wanted a new bottom end

[jonnie205 1]

the fact it was hard to turn over was clearly a problem, anything could have happened to the rod to be honest that cuaed it to break, extreme forces from the worng shells or cap wrong way round etc

[Stu 18]

Oh dear.. I bet that went with a bang..

 

I'd guess one of the big end bolts failed loading up the other while it was running as it looks to have pulled into the rod. Is it possible they were over-torqued?

 

Once thats happened and the cap has come adrift then its pretty easy to imagine the outcome.

[Baz 421]

Christ! Good effort!