BARRON
06-28-2006, 10:41 PM
so I have a 2.5L commonblock I built for my van.
block bored .020" OS
.020" OS Mahle pistons
crank turned .010"
all new clevitte77 bearings
new OEM oil pump
So I leave out the balance shafts and install everything and torque to spec. I should have checked everything with plastiguage but the crank was turned .010 and I bought .010 oversize bearings.. so why bother right? whatever.
I brilliantly weight balance the connecting rods on a scale in GRAMS by grinding away at the pads on the rod caps. Some of us think this is why my engine vibrates and hums like mad. That or the absence of the balance shafts.
Anyways.. it has done this right from the start. Put the scope on all parts of the block here an there and I find that if I rev it slightly I get a VERY HEAVY knock noise in the area of the #4 piston. Its loudest right down where the oil pan bolts to the block. Its not loud at all... but its there.
Now another word about the rods. I never got the small end bushing replaced and resized. It was on the edge of spec.. I should have done em.. but I didnt.
I plan right now sending an extra set of connecting rods down to the machine shop and getting them done.. and replacing the ones in it right now.
ANYONE have any input on this? WHY ould there be a quiet,heavy knock on a freshly turned crank and new bearings?? I KNOW that the small ends of the rods are questionable.. can they KNOCK.. or do they "clack"?
NOTE: I need to install a manual oil pressure guage this weekend too.
block bored .020" OS
.020" OS Mahle pistons
crank turned .010"
all new clevitte77 bearings
new OEM oil pump
So I leave out the balance shafts and install everything and torque to spec. I should have checked everything with plastiguage but the crank was turned .010 and I bought .010 oversize bearings.. so why bother right? whatever.
I brilliantly weight balance the connecting rods on a scale in GRAMS by grinding away at the pads on the rod caps. Some of us think this is why my engine vibrates and hums like mad. That or the absence of the balance shafts.
Anyways.. it has done this right from the start. Put the scope on all parts of the block here an there and I find that if I rev it slightly I get a VERY HEAVY knock noise in the area of the #4 piston. Its loudest right down where the oil pan bolts to the block. Its not loud at all... but its there.
Now another word about the rods. I never got the small end bushing replaced and resized. It was on the edge of spec.. I should have done em.. but I didnt.
I plan right now sending an extra set of connecting rods down to the machine shop and getting them done.. and replacing the ones in it right now.
ANYONE have any input on this? WHY ould there be a quiet,heavy knock on a freshly turned crank and new bearings?? I KNOW that the small ends of the rods are questionable.. can they KNOCK.. or do they "clack"?
NOTE: I need to install a manual oil pressure guage this weekend too.