Any ideas to why this is happening. I'm having new bearing installed in a stock short block for reassembly. After the mains were installed crank turned freely. After every new rod bearing installed it turn freely then once you stopped turn the crank it wont turn w/o extreme force( by that I mean channel lock pliers on timing chain gear and everything I got)and after it broke loose it would turn freely again then stop if after a few seconds of turning. Mains torqued to 75ft lbs then 85ftlbs no problem rod bearings torqued to 20ft then turned another 55 degrees. Whats wrong?

 

My guess would be rod caps got swapped or the rods are egg shaped or clearances are wrong. I swapped caps once and it wouldn't rotate.

 

X2^^^^^^^^ very true, i did it once too

 

I'm positive we didnt mix rod caps but wouldnt it not turn at all? I mean once we getting it turning it turns rather easily. Also it turned fine before new bearings I guess if rods were egg shaped then old bearings were worn down to the shape? I dunno much about this the guy doing my engine seems to be leaning towards egg shaped rods. If they are egg shaped what happens now?

 

check your thrust clearance. try walking the crank forward or backward, if i'm not mistaken you should only have like .020-.030 of walk. if it's too tight it won't spin.

 

Thrust clearance was fine. Crank turned freely and was w/ in spec and once we started putting rods in crank was very hard to turn but once I got it started it turned ok just once Istopped turn it wouldnt turn w/o alot of strength.

 

The torque spec I have on the mains is 77 ft/lbs.

 

I read the 77ft lbs as well but according to the ARP bolts it says 75ft lbs with lube assembly then 85ft lbs with oil. Turning problem started once the first rod was installed. Crank spun freely w/o any rods by hand no problem. My friend putting engine together is leaning towards what some of you guys mentioned which is the rods being egg shaped. Will find out for sure in a day or two once a engine builder takes a look at them. Thanks!

 

This sounds like normal ring friction to me. I could be wrong. Don't use channel locks. Use a wrench or breaker bar on the Balancer bolt. Where is Little Egg Harbor?

 

Kinda that I was thinking. How much lub. do you have on the cyl. walls. What rings?

 

Are you sure you didnt have the Crank turned or it has been turned before, and you are trying to put stock Bearings in it?? I dont know, I did the same thing you are doing and after the whole thing was together with Postons installed it turned freely no pliers needed.

 

LEH is in NJ. Stock rings on stock pistons just wanted to change bearings. Used channel locks on old bottom timing gear which I wont be using going to a double roller so its ok. We oiled the cylinder walled with 5w-30 and used alot of it. Crank wasnt turned I far as I know but it was a short block assembled with old bearing that were worn so it was a working assembly before I got it. I tried using breaker bar on bolt that goes into crank but was so hard to turn didnt wanna break it off inside or strip bolt thats why I used channel locks on timing gears sprocket. Hopefully when I have rods looked at they will be able to tell if rods are egg shaped or not. Oh yeah also putting stock size bearings back in as well.

 

i really hope your checking bearing clearances with plasti-gauge

 

Why arent you using assembly LUBE?? Or is this a Backyard Hillbilly rebuild just to get it running again?? From my experiance those dont usually go well and dont run very long.

 

yes using plastic gauge to measure clearance all checked out. And no hillbilly crap here using permatex red assembly lube as well. I've waited a long time soI wouldn't throw some half azz engine to toghter have alot invested in parts not gonna be that cheap now and not use or check stuff. Rods came back fine says that engine lube is very thick causing a suction that we have to break every time we stop turn. Like I said before once it turns it turns nice no real effort. Clearance of rod bearings was .002 all of them.