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Alan Roehrich · 08-29-2013, 04:14 PM

If it pulled a rod journal/throw out of the crank, suspect a piston/wrist pin problem.

Most often, a crank breaks at the front of #1 journal or the rear of #8 journal if the crank itself is the root cause of the failure. If it breaks at #1, the balancer could be the problem, at #8 the problem is load or fatigue.

About 9 out of 10 times I see a rod throw broken out of a crank, I see a wrist pin or maybe piston problem.

08-29-2013, 04:14 PM	#5
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,113 Likes: 1,571 Liked 1,826 Times in 414 Posts	Re: BBC broken crankshaft If it pulled a rod journal/throw out of the crank, suspect a piston/wrist pin problem. Most often, a crank breaks at the front of #1 journal or the rear of #8 journal if the crank itself is the root cause of the failure. If it breaks at #1, the balancer could be the problem, at #8 the problem is load or fatigue. About 9 out of 10 times I see a rod throw broken out of a crank, I see a wrist pin or maybe piston problem. __________________ Alan Roehrich 212A G/S