johnc55

Hi everyone,

I just got done doing a clutch swap on my MY00 S2000. I had my friend follow me around on the first drive and after about 20 minutes he noticed a bolt get flung up under my car. We turned around and picked it up, and I've spent the past day trying to identify it's location (to no avail). It's a 12 x 1.5 mm thread (17 mm bolt head), which is strange because almost every 12 mm bolt on the car has a 1.25 mm pitch. It also has a "9" stamped on the bolt head, which is also strange because nearly every bolt I can find has a "10" printed on it.

I've narrowed down that it cannot be a transmission bolt. I've checked everyone I can see, and they all have a 1.25 mm pitch. The only 12 x 1.5 mm threads I can find in the service manual are for the subframe bolts (much longer than mine) and for the wheel studs. Does anyone recognize this bolt?

Thanks,
John

baZurk

Trans mount maybe?

johnc55

Thanks for the reply. The rear trans crossmember has 15 mm bolt heads (10 mm thread?), so this is too large. The upper trans bolts (to the crankcase) are 12 x 1.25 mm, which is finer thread than this. They are also quite a bit longer.

Such a mystery. I'm trying to do the 45 minute commute to work in the morning and would like to figure this out. Any more help is appreciated.

stroker

Maybe it didn't come off your car?

johnc55

Thanks for the reply. The rear trans crossmember has 15 mm bolt heads (10 mm thread?), so this is too large. The upper trans bolts (to the crankcase) are 12 x 1.25 mm, which is finer thread than this. They are also quite a bit longer.

Such a mystery. I'm trying to do the 45 minute commute to work in the morning and would like to figure this out. Any more help is appreciated.

johnc55

That's the hope. However after a clutch install with the car just about half apart, I'm paranoid that it came off of mine. If no one recognizes this bolt then I'll dismiss it as a coincidence, but for now I'll have to drive the car hoping it doesn't fall apart haha.

franky

it could be the top or bottom bolt that holds a bracket on the intake manifold to the tranny on the driver side.

MM3Kwolik

^^This

I'm betting its your lower intake manifold brace bolt.

johnc55

The bracket that also clips to the wire harness and a hose? Checked that, top (manifold) and bottom (tranny) bolts are there and tightened. The car is driving great, no strange noises or rattles. Starting to believe it could be a total coincidence... thanks a lot for the help. If anyone does recognize the bolt I would like to know.

flanders

Thought about that manifold bracket as well but it sounds like you checked that.
Anyways here is a picture from under the car where it should be located.