Well I finally got my crank, pistons, and rods installed with new bearings and rings of course. Well everything was going fine and dandy until I tightened the rod bolts to 20ft and an additiona 55deg turn. This is what my manual reccomended. Well the problem is when u try to turn the crank it is very hard to turn. It was so tight that I stripped the first few threads off of my crank bolt. When it is lose the crank and rods will rotate easily. I checked the part numbers on the rod bearings and they came back the right size, stock to fit my stock crank. So should I try to use a diffrent torque reading? Has anybody else had this problem? thanks.

 

What lube did you use on your bearings?
Will the rod caps slide sidways back and forth slightly?
How many rods do you have bolted up?
what kind of rods are they?
New rings?

The torque spec won't effect the crank turning provided they are all assembled correctly.

it is some kind of an interference porblem. did you plati gauge or measure your oil clearance?

 

I used some white grease called no.5 assembly lube, comes in a white tube. The rod caps wont slide from what I can tell. I have all the rods bolted up. They are all stock parts, im just doing a rebuild. The engin was good when i pulled it minus a blown head gasket. Here is the kit i bought. http://store.summitracing.com/partde...5&autoview=sku

 

you need to plasti gauge your oil clearance, as the other guy said

 

say it is too tight then what can i do? Those are stock size bearings.

 

it doesn't matter you still need to check it all...whenever you rebuild you still need to check all clearances for oil,ring gap etc...just cause it says stock does not mean one size fits all. I have a stock crank and had to get 3 sets of bearings before I had something that had the tolerance I wanted

 

You don't say it's too tight until you check it.
...and stop using the crank bolt to turn it...

 

Did you have the crank polished?

Did you have the rods resized?

It is normal for engines to be some what tight. i worked with an old guy that would check the torque required to turn the crank over each time he installed a piston. he figured that it should get somewhat progressively harder with each piston he installed and that the increase should be relatively constant. If the torque required to turn it over took a big jump after instaling a particular rod/piston in relation to the others, he figured he had a problem.

If you didn't have the rods resized, then it is possible that the big end of the rod streched or is out of round. If it is out or round, then the sides next to the bolts may have drawn inward. with the sides pulled in, the hole looks more like an oval than a circle and the bearing clearance will go away on the sides and cause the bearing to compress against the crank and bind.

Greg

 

Did you make sure that the rod bearings were installed on the correct half (rod vs cap)? Some bearings will have an indication on the bottom rather they need to go on the rod or cap and if this is reversed the engine will be very difficlut to turn.

 

do you have the chanfer on the bearings towards the counter weight?