Need some bearing help

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Well we have had bit of a prob with the 200 and narrowed it down to the fact we didn't use a plastigauge when we installed the bearings. We didn't change anything on the crank so we just used stock sized bearings. I had the crank journals polished and that was it. So now we have to pull the engine and plastigauge the bearings. My question is if the bearings aren't within clearance what do I need to do to correct that? Any help will be appreciated. Thanks.
 
You will have to "mike" the journals on the crank. Undersize (thicker) inserts will make up for the loss in journal size. You need to have the crank turned and get all the journals the same size and select the proper inserts. They come in .010, .020,.030. Never had a lot of experience with anything but standard, but a machine shop can fix you up. If you are really lucky, the crank might have already been turned to a size that an undersized insert will fit. If so, when you installed the std. ones, there was too much clearance. If you haven't run it too much, you can probably get by with new inserts of the proper size.
 
No. This is necessary if the mains don't measure the same. Only had to do this one time on a Mopar 383.
 
On a 383? Wow, that thing must have seen some abuse, those things are so stout in the bottom end they almost never need align bored or honed. As far as bearings, occasionaly the wrong bearings will come in the package. Its not too hard (nor is it common) for one or two undersize bearings to find thier way in to a standard set.
 
I got the 383 in an old Charger. It probably had been abused. The machine shop checked everything out and recommended align boring, so I told him to go ahead. I always check the marks on the new inserts and plastigauge them as well. Can't be too careful.
 
I had my crank micro honed and polished while I had my engine apart. I used standard size bearings when I put everything back together and now it is so tight it won't even turn by hand. Does this mean I need to go with undersize bearings? To figure out what size I'll need to plastigauge the mains and should I do the rod journals as well?
 
No. Undersize will make it tighter. Undersize means that the crank has been ground and the inserts are thicker to make up for what was cut off the crank. Always plastigauge both mains and rods. Did you put some moly grease or STP or something on the inserts before you torqued them down? Will it turn at all? I have had some that the mains were pretty tight and didn't want to turn by hand. Usually if everything is OK, after a few turns with a pull bar, everything is fine.
 
ummmmmm yeah if you had it polished and honed and it will no longer turn by hand you have a problem:

1. You got the wrong bearings
2. You tourqued something wrong or have a cap mis-installed
3. Trash somehow in the there (when I assemble and engine it is operating room clean.
4. Numerous other things

My bet is on 1 or 2 though, probably 1. as I have seen parts stores hand out the wrong bearing on more than one occasion (IE if you put .010 bearings on a stock crank...).
 
I have seen one rod jornal on a crank ground smaller than the rest. It really doesn't take long to measure them all with a micrometer. Any chance that the caps got mixed up?
Joe
 
1. Kept it very clean
2. Torqued it according to the specs in my chilton manual and in the sequence they suggested
3. Used assembly grease

it will not turn at all, bearings were supposed to be standard size...hmmm now I am beginning to suspect I was given the wrong bearings :evil: . I will have to do some measuring.

I installed all the caps exactly as they came out, but I will check the alignment :wrench: .

Thank you guys for helping me trouble shoot this, I do appreciate it. I'll keep you posted on my findings and out comes. Thanks again!!
 
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