One rod clearance at .006", most at .002-.003"
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One rod clearance at .006", most at .002-.003"
The odd thing is, the other rod on this journal is at .00175" or so. I got this motor second hand, the block was new, the reciprocating assembly had a few thousand miles on it if I recall correctly. Can I get an oversized bearing to compensate for this? The journal on this rod looks perfect w/o any scoring either. I'm stumped as to why one rod would be like this.
Thanks
Dave
Thanks
Dave
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The odd thing is, the other rod on this journal is at .00175" or so. I got this motor second hand, the block was new, the reciprocating assembly had a few thousand miles on it if I recall correctly. Can I get an oversized bearing to compensate for this? The journal on this rod looks perfect w/o any scoring either. I'm stumped as to why one rod would be like this.
Thanks
Dave
Thanks
Dave
For a 2.100" pin, the rod big end housing (without bearing) should be no smaller than 2.2247" and the crank pin should be around 2.9990" or so.
What you could do is get some Clevite 663-10 (745-10 for 2.00" pin) rod bearings, measure the ID of the bearing torqued in the rod, and have the crank ground to a number that would achieve your desired clearance, say .0022"-.0028"
Double check to make sure it's really .006" clearance before you go doing anything reall drastic. Make sure the rod bolts are properly torqued/stretched to spec, everything is clean with acetone or laquer thinner, and the right bearings are in the right locations. As far as I know there isn't a bearing out to take up about .003", and it probably wouldn't be right to have to do it on just one rod.
Hope that helps. Let us know what you find.
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i went ahead and took another rod bearing from a rod that had a good clearance and put it in the bad (or so I thought) journal and sure enough i'm at .002". Must be a bad bearing. I'm going to replace all the rod bearings and recheck their specs. If the crank bearings are at .0015" should I Just leave them? I see no scoring in any bearings or surface..
Dave
Dave
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new clevite 77s .010" over got me to .020-.030" on all rod bearings. I used plastigauge so I cannot get any more accurate than that. All mains were at .0015". Hopefully all goes well from here on out.
Dave
Dave