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Finally scored a 4.2 crankshaft

Posted: March 28th, 2016, 7:32 pm
by lamart72
Hello, I have been lurking here for a while, reading everything I can while looking for a crankshaft to start my stroker project. Well today I finally scored a 1988 4.2 motor for $75. The owner said he had the block bored .030, the 3727 crank ground .020/.020 and the head redone. He ran it for about a month but ran into problems with the valve guides. Apparently they did a very poor job of knurling the guides and it was passing oil down the guides and smoking heavily. He pulled the 4.2 head and the motor sat for several months in the salty air near Corpus Christi. He recently had heart surgery and decided to sell the 4.2 on craigslist. I called last night and picked it up today. He did warn me about the surface rust on the rod bearing surfaces and bores. I know I can get it ground down to .030 but I wanted to try cleaning the surface rust off of the crank. I am going to try using electrolysis to remove the rust. Has anyone here ever used this method to remove rust from a crank before? I don't have too much in this motor and I have seen what others have done on youtube. My only concern right now is the crank as I know I can sell the rest of the parts to recoup my money. Here is a pic of the crank.
crank1.jpg

Re: Finally scored a 4.2 crankshaft

Posted: March 28th, 2016, 9:20 pm
by Cheromaniac
Some fine emery paper will get rid of that.

Re: Finally scored a 4.2 crankshaft

Posted: March 28th, 2016, 9:21 pm
by IH 392
Take it to a machine shop and have them polish it.

Re: Finally scored a 4.2 crankshaft

Posted: March 28th, 2016, 9:48 pm
by Russ Pottenger
IH 392 wrote:Take it to a machine shop and have them polish it.
^^^ This,
... and if it won't clean up they will have to grind it.