Replacing a crank shaft questions
My engine is a 1971 340 (august I think). Externally balanced.
I have a manual for 1968 and the only thing it says regarding identification is whether I have a Maltese Cross stamped on the “numbering pad on the right side of the block” . It may have undersized one or more bearing journals by .001. If it is stamped with that cross and an X All of them are .010 undersized.
Is this Maltese Cross Id still true in 1971 or 72? Do I need to worry about it if it’s heading for the machine shop? Where is this numbering pad? Will any LA crank shaft work or is there something specific I need to target?
Thanks in advance
mopar casting numbers
Saw this on another post. Will the cast 72 crank work in my 71 motor? Is the only difference that they were steel up to 72 and cast after 71?
The engine is at the machine shop 2 hours away. They tell me today that the crank shaft is toast and they can’t find one??? I’m attempting to get them some information to properly identify what I have so we make the correct choice on the replacement.
What I think I understand is that any crank from 68-71 will work with this engine despite how many times it’s been line honed as long as the bearings are matched properly. Is that right?
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It needed a line hone 6 years ago and that shop said the crank was just Ok then. So I went with it...
Okay, hold the phone, back up the bus, hit the "reset" button- this is starting to read like a bad dimestore paperback whodunit that keeps revealing new information after it's all over. You started out asking about block markings and factory undersize crank journals, then start talking crank swaps, and then bring up that it was already line honed when you were into it 6 years ago?
Factory block stampings don't mean chit fifty years later, once you (and who knows how many other previous owners) have had work done to the motor, replaced parts and been into the short block. You need to check and verify dimensions- isn't that what you're paying the shop to do?
Line honing is a block correction procedure and does not affect the crankshaft or the fact that it may have undersized bearing journals.
And personally, I wouldn't trust a shop that cannot find a 273/318/340 crankshaft. Grab your toys and take them home.
So, let's start this over and get the whole story all at once, not piecemeal. What you have, what's already been done to it (as far as you know), what the problem is with it, what you're attempting to have done, and what they're telling you. Asking for advice without giving all the information is just inviting more problems.
