perlandas

Really?

Jstuning_

i missed to read the part about thicker oil, that usually helps against piston slap/slam.
but if its piston slap you can hear the noise higher up in the engine, if its more in the bottom its more likely crank or rodknock.

the s2k frm sleeves are a bit different and its maybe the machineshop did bore to much clearance and than the engine block is toast. But thats should always be control measured at assembly. I have taken apart engines that had the double clearance after rebuild that was recommended by the piston manufacture.
machineshops can do dirty work to.


Its very easy to creat like a stetoschope to listen if the sound comes from bottom or top of the block or the head.

perlandas

The tuner used a stethoscope but it was still hard to exactly pinpoint where, he did say he heard it most from the bottom. If it's from there then that could explain why it's so present in the cabin and pedals. Yeah could be a machine shop mistake, I believe it was done by an expert
and cost a fair bit to do because of the complicated engine, but mistakes can still be made I guess.
I really hope it's not the block, that would pretty much wrap up this season for me, and the budget I had for other exterior/interior upgrades & refurbishes I planned.

dagle

hmm if the oil came out clean, it's unlikely to be rod knock but i'm still a bit skeptical because it's been rebuilt with no details known to us. i've known plenty of s2000 guys over the years that are faster than me who refuse to reuse F20/F22C cranks that have spun and i personally am one of them too. if the crank inside the car was hurt before, i would look there. the small journal could be doing something whacky. i'm doubley cautious to the point that i personally cleaned and inspected everything, replace the oil pump, VTEC solenoid, etc. it could be piston slap if the tolerances were too generous but it would be strange to only happen at 2000RPM regardless of temperature. i have a rebuilt engine with piston slap (my oil is clean and blackstone oil analysis came back clean too) and it goes away when the piston grows from heat. before tearing down the block further, might i suggest checking the engine/trans mounts to make sure it's not harmonics from external components? i've had similar phantom noises from the oil fill cap falling in between the engine and chassis, motor mounts gone bad, ratchet wedging itself between header and chassis, etc.

B serious

Why did the new-to-you engine need a rebuild?

I guess its not helpful at the moment...but buying a used, factory assembled longblock is the most foolproof way to go. Rebuilds have a low success rate.

Or...K swap it and keep spare engines on hand.

Slowcrash_101

The cranks cannot be reground. Polishing the crank is pretty much useless without a profilometer(which is boucoup bux). Since the crank is forged, normal polishing methods will not remove material, it will look smooth to your eye, but if you look really closely there will be all sorts of peaks on the metal, these peaks will chew up the bearings. If an OEM crank has spunk a main or rod, the crank is pretty much useless. The labor and effort that would go to make the crank usable again isn't worth it, you're pretty much better off buying a used one.

fatjoe10

Sounds like main bearing issue... any way you can do an oil pressure test? interested in the reading at 3,000 RPM.