When checking measurements before installation of torque converter all are OK except that the 0.44" converter pilot won´t fit in the 0.38" deep crankshaft, measured from crankshaft flange.
The problems seem to be common, here are a few other threads;
Thread 1,
Thread 2 and
Thread 3.
But I can´t find an explanation for this problem. Is it stacked up tolerances, faulty (re-)manufacturing or wrong specifikation?
In my case the converter is a MP "econo" converter part no P4876870 that is used with a non lock-up 727 from 1978, part no 4058114. The recommended flexplate P5007378 did not fit the profile of the converter, instead a B&M 10231 is used.
Crankshaft is aftermarket but, as I understand, with similar dimensions as mentioned in Thread 3 (0.638 deep measured from a 0.256 tall register) so I conclude its useable.
A comparison between the MP and B&M flexplates show that the B&M is 0.480 tall and 0.126 thick, the MP is 0.377 and 0.111. The profiles are also different. This is hardly a faulty manufacturing but rather a different specification for different converters. But in litterature all non lock-up 1966- converters are described as interchangeable which they obviously not are.
An attached print out from an old Transtar catalog shows converters with thin and thick pads. Can they replace each other?
In the threads above, the converter is often replaced. But what converter specification should I use then?