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Hi... Man, here I go again...... Guys , just slap me!!! Yep...you gotta get a micrometer (a 2-3" and a 3-4" for the 2.0L), learn to use it (takes a little practice but it ain't hard) and then mike the bearing journal surfaces to determine the size....I've gotten away with "rough" measuring with a inexpensive vernier caliper to determine "standard" or "undersize" while poking around in a salvage yards etc., but for real rebuild accuracy, you need the mikes. I don't have any specs in front of me right now, but I believe the mains on a 2.0L are 2.500" standard...someone correct me if I'm wrong on that... IF the motor has never been apart, more than likely you're looking at a standard size, but you just never know till you measure em....crazy things happen at the factory sometimes....especially Chrysler (yeah, it's a Chyrsler). Measure at each edge of the journal and at the center to determine if you have any journal "taper" that is outside the spec limits. Main bearing journal taper is not common on these cranks...at least I've not seen it in any I've had apart. I think thats because of the rigidity of the bottom end due to the bedplate design and the relatively short length of the crank. I have seen a little bit on a couple of rod journals in one motor that had lots and lots of miles on it, but it was still within the tolerences spelled out in the service manual....it was very slight. I'm sure that not all of em are that way...I've just not seen any in my shop. IF I cannot catch a fingernail on those journals and there is little or no out-of-spec taper and there is no scouring/pitting etc. (IF any of those conditions exist, the crank needs to be ground undersize to get it back to pristine with no taper and to get those flaws out and what follows below will NOT work). I mount the crank vertically in my shop press just barely enough to hold it tight, yet not destort it... I start with just the right length piece of 240 grit emery cloth to get it wrapped and slightly over-lapped around the journal. I use a piece of rawhide string (you can use an old cloth-type shoe/boot lace, but be prepared to suffer string burns on ya fingers...lol..and it doesn't hold the emery as well either) wrapped around the emery cloth one complete wrap, then take the two ends of the rawhide facing you and GENTLY polish the journal with a tight, but gentle, smooth back/forth motion. With a little tension on the rawhide and a little practice, you can "walk the rawhide(not the emery cloth) up/down the journal giving it a nice pretty overall polish that removes most, if not all, of those very fine lines you're seeing (oil wipes is what I call em)...gently is the word here...don't go hog wild and overdo it ruining the journal. I finish it off with a piece of 500 grit cloth the same way as above to get it to a real nice pristine finish.....then clean, clean, clean....and clean it again....hot soapy water, oileater or purple cleaner... whatever it is that you use to clean with...hot water...soap...clean it again, but get it clean....did I say, "clean"?? Use a small engine brush and clean the inside of the oil holes in the journals as well (careful, you don't scratch your nice new polish job with the end of the brush though)...completely blow it air dry, including the inside of those oil holes and immediately oil it down...yes, I still use good old WD40 because it will displace any minute moisture that may be left behind...use whatever, but do NOT let it dry out leaving it wet...it will rust!!! Hot water evaporates quickly not allowing time for rust to form as fast.... key word: "hot water". Once you got it oiled down, store the crank in the vertical position.... Do NOT let it sit/lie in the horizontal like it sits in the engine...it will ever so slightly....BEND!!!! Without it being supported by the bearings, it will bend..especially cast steel ones like these. This may not be as much as factor on these short stout 2.0L cranks compared to say an old in-line 6-cylinder or a big V8, but it's still a good idea and practice to store it in the vertical....cover it loosely with a trash bag to keep the dirt/dust off it...(even though you WILL clean it again prior to actual assembly). Leave the bag loose so that condensation doesn't form on the crank yet it keeps the dirt off....IF you got any of those little dessicant bags that are still good, toss em in there, but don't let them rest/touch the crank...they will cause rust. For a long time, I'd cover/tie it off with string in a corner somewhere outta the way so that I didn't accidently bump it an knock it over. Now, I have a wooden "crank holder" that I built that holds the crank vertical by it's rear flange... Oh yeah, that's another little thingy on the 2.0L crank, the outside surface of the crank flange is a seal area... Do NOT let it get nicked/scratched/rusted/banged/dented etc. and it should get a little cleanup with some 240 the same way the journals did.... That string/emery cloth thingy is an old trick, but been doin it for years. I've got motors that now have well over 100,000 miles on em that I've done this to without a bearing problem....but it only works to clean up slight oil wipe lines. You cannot do it to correct major flaws. Golly, I gotta get outta here.....sorry.
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