Thread: Twisted Crankshaft Help
09-25-2008, 03:28 PM #1
Twisted Crankshaft Help
I'm rebuilding a 580 white engine for a friend. He picked it up for almost nothing as it had blown the two front crank bearings. All of the other bearings are in mint condition. No shavings in the cases, the balls made it out the exhaust without damaging anything. I thought that the front two bearings blew cause of a twisted crank.
I put the crank between centers on a lathe and got .030" deviation on one end. I figured out what needs to move in what direction, but I was wondering what is the official technique for doing this. I was wacking on the crank with a brass hammer, and was moving it .001 or less each time. I think I am going to try the 20ton press tomorrow, unless someone has a better idea.
09-25-2008, 08:03 PM #2
IMO I think you already spent more time than its worth.. You get all done with trueing and put your new bearings on and assemble the engine then you find out the center crank seals are worn and the crankcase fills with oil after setting for a week without running then you get to do it all over again..
09-26-2008, 12:21 PM #3
At the top of the page where all the threads are is a link for service manuls. I think they have the official procedure for what u are doing. Good luck and I don't think its a waste of time if u like doing it and learning something while u r at it!
10-02-2008, 01:06 PM #4
Update, I got the crank trued and phased again! Not too hard, just need dial indicators, V blocks, surface plate and a big hammer!
10-02-2008, 01:50 PM #5
How did the center crank seal test after doing alll that?... Ron
10-02-2008, 03:01 PM #6
Crank seals test? Not sure what you mean, but they look in really good condition. The test will be when I put it all back together.
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