Identify this nut from my SR20 oil pan

[louren]

Well, this is a game I was hoping I was never going to play, but here I am.

Drained the oil on my SR yesterday and noticed some metal shavings on the magnetic drain plug. Pulled the pan today and found a small 11 mm nut at the bottom. I figure I'll be pulling the motor regardless at this point, but.. does anyone know what this is from?

https://c2.staticflickr.com/2/1958/31768821908_9367de899b.jpg

https://c2.staticflickr.com/2/1958/44916182774_384c86d1c7.jpg

https://c2.staticflickr.com/2/1902/45641087481_2b5508ea7e_z.jpg

[kyral]

piston rod cap nut.

[jedi03]

those are usually 12mm unless someone rebuilt it...would have to pull pan off to see if one is missing...tho theres not really many nuts goin into the inside of the engine...

[kyral]

those are usually 12mm unless someone rebuilt it...would have to pull pan off to see if one is missing...tho theres not really many nuts goin into the inside of the engine...

I thought 11mm was weird but like you said there is not many nuts goin on inside of there. idk what else it could be

[Kingtal0n]

didn't you know, every SR engine has one of those in the pan. Nothing to worry about...


:D

guesses:
failed pickup tube nut?
failed cam-cap install nut?
somebody may have found an 11 and not realized it wasn't 10mm, tried to install it somewhere, and then it rattled off. Look for a missing nut somewhere...

[louren]

Bump - any help would be greatly appreciated.

I've pulled the lower, upper oil pan, the valve cover. There's no sign of where this nut came from anywhere.

[jedi03]

if no nuts are missing anywhere prob just fell in during assembly...

[louren]

failed pickup tube nut?
failed cam-cap install nut?
somebody may have found an 11 and not realized it wasn't 10mm, tried to install it somewhere, and then it rattled off. Look for a missing nut somewhere...

I don't think the pickup stud has nuts, just bolts?

if no nuts are missing anywhere prob just fell in during assembly...

I've had the pans off before and it wasn't there, so unfortunately it has not been there since assembly.

[Jefro240]

If you look at the valve train, head, cylinders, front cover, pans etc etc... You only find 2 nuts... Connecting Rod & Tensioner with only 1 of them being internal. If it didn't come from a connecting rod then I got no clue where it came from. No other nuts in the bottom end.

No Nuts...
https://nissan.epc-data.com/img/RS13/110B_001.png

Connecting Rod Nut
https://nissan.epc-data.com/img/RS13/120B_001.png

Only Nut is the Chain Tensioner
https://nissan.epc-data.com/img/RS13/130B_001.png

No Nuts...
https://nissan.epc-data.com/img/RS13/135B_001.png

No Nuts...
https://nissan.epc-data.com/img/RS13/150B_001.png

[louren]

If you look at the valve train, head, cylinders, front cover, pans etc etc... You only find 2 nuts... Connecting Rod & Tensioner with only 1 of them being internal. If it didn't come from a connecting rod then I got no clue where it came from. No other nuts in the bottom end.


Thank you very much for the detailed drawings, appreciate it. Can you help explain to me how you read it the bolt / nut sizes?

The connecting rod nut is '12112', so the 12112 is where you get the 11 from?

Based on that, I don't see how the tensioner nut is an 11? The tensioner nuts are outside the engine anyways, so there's no way it could have ended up in the oil pan.