Crankshaft sticks

[dutchmeister]

Rebuilding a 230 ci top and bottom. Had the cankshaft milled to 10 under and new bearings (also 10 under.) Main bearings in and crankshaft spins easily. Can get 1 through 3 rod bearings in and crankshaft turns but is harder. When I torque (at 40 lbs.) #4 the crankshaft sticks. Any ideas aside of having the crankshaft re-mic'ed?

[lugnut123]

get some pasti guage and check what the clearance is on that one bearing. if you have not used plasti guage before the little piece of pg you use you put on the crank in the area you put your bearinf/ insert. Tork down your cap and the guage will squash down. Check how wide the squash part is and it will tell you your clearance. Hope that helps Did you get your push rods resized?

[Dodgeb4ya]

Are the bearings made by awell known USA bearing manufacturer? The white box Chinese engine parts are junk-inferior materials. I like to mike all the crank journals that I had the machine shop do the crank work.I also have the rods hung and aligned- big end honed to size and new small end rod pin bushings honed to fit new pins.

I then assemble the rods and mains with bearings in them of course out of the block and torque the caps to spec and use micrometers or bore guages to check the bore diameter of the mains and rods with the bearings in them.This assures me of proper oil clearances before I start to assemble the engine. Plasti -gage will work too. The crank of course should never be hard to rotate in a new engine with new bearings. The installed new pistons and rings Will cause the use of a lever or large socket to rotate the crank as they cause a lot of frictional drag on a new engine. Never bearings.

Bob

Edited December 24, 2010 by Dodgeb4ya

[Dave72dt]

Check the rod for straightness, brg for size and that it isn't turned 180 degrees. Undersize should be marked on back of brg shell, both halves. Wouldn't be the first time shells were mismatched. Also, check that the rod cap belongs to that rod.

[dutchmeister]

All the rod caps and rods are numbered 1-6 and are matched correctly, the oil hole points to the pump and cam. Good point about the rods being bent. The engine was froze up and we tryed towing in in gear and popping the clutch to break it loose. Didn't work, and it was a dumb idea. I'm going to take the engine back to the shop that did the mill work. Supposedly they checked the rods at the time. It's a royal pain when something that should be easy isn't, and you don't know if you've done something wrong or something is wrong and nothing you do will work.

There is a groove in the cap and rod where the bearing's notch fits, so a 180 misplacement isn't possible, but that's a good point to check the size. I did it with a few of them but not all.

Bearings made by Hastings.

Thanks for the rapid responses and the good ideas.

Edited December 24, 2010 by dutchmeister

[greg g]

Are your rods installed with the offsets correctly oriented?

[John-T-53]

I had a similar problem last summer when I did mine, except it was with the mains. The bearings were one size too small, and it wouldn't rotate at all. Looking back, even placing the crank in the upper shells seemed tight.

Did your shop hone the rods too?

[Phil Martin]

Be sure you don't have any caps in the wrong place.

[rustyzman]

Gotta mic the journals first. Ideally, you should check the clearance on all the bearings when you reassemble, just to be sure they are right. Sucks to find out something is wrong after assembly and installation. Better to know now.

Totally possible that you have a misboxed bearing or that the crank is not ground correctly on that journal.

Plastigage is another good idea.