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Driving myself crazy with cold engine noise (after rebuild)

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Old May 12, 2021 | 08:47 PM
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Default Driving myself crazy with cold engine noise (after rebuild)

So this winter I brought my block to a well respected local builder (does a bit of everything).

it’s a 1.8 with refreshed oem pistons, new rings, fresh hone, Manley rods, acl bearings, arp main studs. He polished the crank and ended up having to bore the piston wrists a bit.

I’m about 800 miles into this build but whenever the car is cold or has been off several hours I get what I can only describe as a tick that is different than solid lifter tick or rod knock. The sound seems to go away completely once I get a little heat into the engine.

with a stethoscope I think I’ve possibly narrowed it down to cylinder 4 but to be honest they might all make the noise to some degree and I’m just imagining 4 is worse. When the car is at temp and I place the scope near each cylinder they basically sound the same.

ive changed the oil like four times since rebuild and only note the fine glitter that is apparently normal, which definitely is less intense every time I’ve changed it. I popped the valve cover off to double check my lash. I adjust lash myself while the lower end was at the machine shop. I erred on the side of loose for exhaust... pretty much all 0.012-0.013. Not notable debris in the residual oil that was pooled in the head during my lash double check. I did bring the head to the machinist for new valve seals prior to dealing with the lash.

I installed a real oil pressure sensor during rebuild. Oil pressure is way up there in the cold starts, it’s 50ish degrees in mornings right now and I’m running Dino rotella 10w40. Pressure if I remember right is like 60+ when idling cold and just a hair over 20 when the oil is 200F at idle.

from my reading, the sound could be either piston slap or possibly wrist pin noise. Or maybe it’s nothing and I just need to stop looking for something to worry about.

I can hear it when using earbuds in this video. Somewhat irregular rhythm “cha cha cha” “cha cha cha”

Old May 12, 2021 | 10:18 PM
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Originally Posted by c3hutson
... and ended up having to bore the piston wrists a bit.
Can you clarify what was done on this?
Old May 12, 2021 | 10:24 PM
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What I meant to say is that he had to hone the pistons for correct pin clearance
Old May 12, 2021 | 10:26 PM
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Originally Posted by c3hutson
What I meant to say is that he had to hone the pistons for correct pin clearance
I've never had to do that, it does strike me as odd given you have a ticking sound when cold. I wonder if that was really necessary, or if it was opened up too large?
Old May 14, 2021 | 10:38 PM
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Sounds like my engine, except I have wiseco pistons.
Old May 14, 2021 | 10:57 PM
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here are my clearances.





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