don,t guess on clearances and journal surface



don,t guess on clearances and journal surface

Postby grumpyvette » November 15th, 2013, 11:26 am

adam wrote:So I decided to buy a couple of worthless old 283s to learn how to build engines. If I acquire the appropriate skills, I'm going to build a torquey 383 out of the anemic '77 350 in my C30. It tows cars, but it doesn't exactly set the road on fire, if you know what I mean.

Anyway, I bought two 283 short motors, a pair of heads, intake and carb, and a few other things for $200 for the purpose of learning to build motors. The better of the two short blocks is + .040 and has a minimal lip on the bores. I pulled the pistons today though, and I found that one big end journal on the crank has a pretty decent set of scores on it. I can feel it easily with my finger, and the bearing for that rod was pretty scratched-up looking. The other 7 rod journals are good.

So, if I reassemble this beast with the same bearings, no crank grind, just clean the parts and put it together, how bad will it be? Will it last 10k miles? 10 miles? Any engine builders there got any input?

Thanks in advance! Adam from Melbourne, Australia.



viewtopic.php?f=44&t=10923

without pictures and measurements of that crank journal, that questions a bit like asking how pretty the next girl thru the door might be based on the color of her tooth brush at home!

reading a few links and sub links carefully could save you a lot of money and time

viewtopic.php?f=53&t=9214&p=33116&hilit=crank+journal#p33116

viewtopic.php?f=53&t=2726&p=7077&hilit=plastigauge#p7077

viewtopic.php?f=59&t=1390&p=3073&hilit=precision#p3073

viewtopic.php?f=53&t=5478&p=16429&hilit=plastigauge#p16429

Im rather confused, why not just have a local machine shop, inspect both cranks,and either cut and polish any worn crank journal on the best of the two,to a standard under size , and supply matching new bearings or buy a new crank, they just are not that hard to find at a decent price.
and while your at it why not have the local machine shop inspect your block, and it necessary bore and hone it if it checks out as rebuild-able?
not much point in building an engine without building it to function and last a long time, and you do that my making sure all the components fit and function as designed with the proper lubrication,oil flow,oil pressure, compression and clearances

viewtopic.php?f=51&t=125

viewtopic.php?f=54&t=1479

viewtopic.php?f=51&t=976

viewtopic.php?f=51&t=7697

viewtopic.php?f=53&t=852

viewtopic.php?f=53&t=247
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
grumpyvette

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