k1 rods side clearance???

noahzark

Member
Joined
Feb 13, 2007
...so k1 rods call for .008 to .012 side clearance from the rod to thrust side of crank...im only getting about .006...i have only done my first retorque on the rods of 30 ft. lbs. plus 60 degrees on the torque angle gauge...is this going to be a problem...do i have to send it back to the machine shop for them to adjust the crank?...im going to loosen the rod bolts three or four times and retorque and hopefully the rods will center on the pins of the diamond pistons other than that any suggestions on what is ok for rod side clearance?...thanks for help...noah.
 
Did you have the rod bearings chamfered? Some of the aftermarket cranks have a big radius and that could be reducing the side clearance.
Jeff
 
...bearings are out of the box...but they are fairly thin and barely even reach the sides of the rod and rod cap so i dont think its that...thanks...noah.
 
...anyone have any rod side clearance specs???...k1 rods and cat crank...thanks for help...noah.
 
Put a piece of feeler gauge stock at the bolt areas, to keep the cap from twisting when you tighten the bolts.
Also, BE SURE the socket is not being forced against the cap.
As mentioned, CHECK the chamfer...Blue the edge of the brg, then push the rod to 1 side, and move the crank...Is the bluing disturbed? If so, then the brg is controlling the side clearance, not the cheek of the rod..
 
...well this engine build is really starting to get to me...2300 at the machine shop...the rod bearings that they gave me are the clevite 77 cb 1228-p...my side clearance on the rods is at about .005 and k1 notice says i need .008-.012...the thing is that the bearings are very narrow and dont even come close to the cat crank fillets its the actual rods that press against the crank giving me a tight side clearance...so hellllllllllllllppppppppppppp!!!!!!!!!!!!...are thse bearings ok is that side clearance ok??? ...if not do i get the 1398 chamfered bearings and chamfer them more or do i go back to the machine shop and machine the sides of the rods and then rebalance everything??...

...what the hell is going on...love these buicks but damn i want to drive the damn thing...thanks for help noah.
 
... i guess i can try that ill have to wait till monday now...not sure how that will make the difference...i measured the rod and i measured the crank journal...and the clearance is .005...wont matter what bearing i put in it the bearing isnt going to shrink the rod nor expand the crank...i can only get .005 side clearance no matter what...so i guess the next question is can the engine live with that tight clearance?...i have heard of .006 so maybe .005 will be ok...my only option to change that is to machine both sides of the k1 rod down by .0015...in order to get .003 to add to the .005 to end up with .008....seems like pretty minor measurements to be screwing around with the rod and i havent seen a post where anyone has machined the rod down...so anyone out there run tight rod side clearances and have their engine survive run well and last???...thanks again for help...noah.
 
as primitive as it sounds, tq the cap to 30 or so and smack it side to side with a deadblow hammer and re-check.
 
...well i think that clearance is just a bit too tight...so after some good advice i think i will take off 4 or 5 thousandths off the side of the rod ...seems the right thing to do and from what i hear not that uncommon when piecing together all these aftermarket parts ie cat cranks and k1 rods etc...thanks for help...noah.
 
just checking the clearance on a stroker with K1 6" rods and DLS BA crank and I'm getting .006" side rod clearance .
 
when i checked my k1's to the stock crank i had the same problem,side clearance was all over the place,it was not the bearings just the side of the rod was too close to the fillet on crank,had to machine down side of rods to get them within spec.if i remember a couple of rods were different thicknesses but most of it was the crank.
 
I had to increase the chamfer on my bearings, this was on a CAT crank as well. I couldn't even torque the rods down without the rotating assembly seizing up.
 
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