Brandon031

Ok I picked up a s13 sr and the guy said it had a rod knock. He figured it was a spun bearing. I did a complete tear down and spun the crank everything was smooth and no knocks..
took off the oil pan and I didn't find any metal shavings. continued to tear down the engine and all the bearings were in place. The pistons popped out with no problem and the cylinders where fine smooth no nicks or dents. Really no sign of a rod knock. Ima rebuild it but just wondering what could have made the noise that made the guy think it was a rod knock? Also what parts can I reuse going to a oem rebuild.

Thanks

ShadowMan

I rebuilt my sr a bit ago. I detonated piston 4 down to the ring lands, so I ended up replacing all the pistons with new oem ones, but reused the rods, so far so good. Check the clearances on everything or take it to the machine shop that will hone and deck your block and they will be able to tell you if your crank and rods are good. I also went all new bearings, arp main studs, rod bolts, and head studs. Might as well go with a new oil pump and new front and rear main seals. When you have the block redecked, have it done with the new oil pump/timing cover bolted onso it's all the same. I didn't and so far it hasn't caused any problems but I probably got lucky as it seems some people have had problems with cylinder 1 sealing properly. I went thru frsport and their techs were cery helpful helping me get what I needed. Not sure if I went over board here with this response but hope it helps.

__________________
in any situation....thou shalt blaze

Brandon031

Thanks that helps a lot lol
And I think ima just reuse my rods and replace the rest to be safe.

nissanfreak317

Rod knock does not always equal spun bearing. Basically, if the motor spun a bearing, it would most likely be seized and you would be faced with replacing that rod and grinding or replacing the crank depending on the severity. Since you don't mention that it was seized, you probably got lucky and either found someone who doesn't know what rod knock sounds like or you found someone honest enough to tell you about it so you could fix it before it became a real problem for you.

Anyway, spinning the crank wouldn't reproduce the knock unless it was really severe. If you had it upside down and rotated the crank so you could get to the "big end" of the rod easily, you may have been able to feel a slight wiggle if you were to grab each rod end and try to force it up and down or back and forth. A slight knock probably wouldn't show massive amounts of oil shavings in the pan either. The condition of the cylinder walls has nothing to do with it, pistons coming out easily has nothing to do with it, and all the bearings being in place has almost nothing to do with it.

Good luck with the build on the motor though. It's good peace of mind to know that your SR has a fresh bottom end. Please take it to a real machine shop and let them check it out and assemble it for you.

godsmack

Might of even got really lucky and it was just the timing chain slapping off of the top guide and the guy couldn't tell. But like everyone else said, take it somewhere respectable and all that jazz.

shagspeed

I would also 2nd ShadowMan's assessment .. Only thing to concider is the head studs .. ARP's sometimes need to be checked every now and then .. The factory head bolts are a stretch bolt .. Yes they stretch there by maintaining a constant TQ at all points of the heat cycle .. ARP's do not give at all as it heats and cools it compresses the head gasket and will lose its TQ .. So if you go head studs heat cycle it 5-10 times or after 500-1000mi and TQ them again and check them again at 6mo or so.. But beside's that you got lots of great info from Shadow ... Best of luck ..

ShadowMan

Can't believe I left that out, but yes a retorque on the head studs is highly advised 500-1000 miles down the road. The milage depends on who you talk to. I retorqued them after a tad over a 1000 due to work schedule and all is well. They remained torqued at 80 lbs and hadn't backed off at all. And the piece of mind knowing that they were still good was worth the trouble of pulling the cams to find out. Make sure you purchase a quality torque wrench that can handle all the torque specs you'll be using it for. Like I said, ARP's final torque is 80-85 ft lbs. Good luck and I hope you have an FSM handy, mine was priceless in this process.

__________________
in any situation....thou shalt blaze

shagspeed

Yes... a good Torque Wrench is key ... Don't use some Harbor "China" Freight or Sears Wrench either ... Matco,StrapOn or CDI .. Heres what I would use its made by StrapOn I mean SnapOn Tools

CDI Torque Products, CDI Computorq 3 HA Torque Wrench: Pro Torque Tools

I hope this thread answers all your questions.. If not ask away ..

Brandon031

Thanks and its all going good sofar lol and the advice helps a lot.