Metric Bolts

[kroberts]

I need 8 bolts,12x1.5mm, with about 35mm of thread. They are for a flywheel so I wont be visiting Home Depot to buy these.


Can anyone offer any advice concerning bolt grades?

Where do you buy quality hardware? Links?

TIA

[dashboardmonkey]

Find an industrial supply company.

Here we have fastenal and r&s industrial.

mcmaster.com has bolts and such as well

[Massive Lee]

These bolts are 12.9 and have a shallow head. I highly suggest getting them from the dealer. But beware, they come in two different lengths depending on flywheel.

Lee

[nando]

don't use just any generic bolt.. the stuff that holds the pressure plate to the flywheel is one of the highest stressed parts of the car. Get bolts made for a flywheel and nothing else.

[kroberts]

don't use just any generic bolt.. the stuff that holds the pressure plate to the flywheel is one of the highest stressed parts of the car. Get bolts made for a flywheel and nothing else.

Hence my post

[nando]

well assuming you aren't too familliar with the ETK

https://www.bmwfans.info

www.realoem.com/bmw/

choose one, look up the part #s and order from your favorite dealer/parts seller (bma, pelican, bavauto, etc).

[FredK]

What kind of M12 bolts did your flywheel originally come with? And did your flywheel come with a "gaul" plate?

kroberts is searching for bolts appropriate for running a lightweight flywheel. I know that the original equipment bolts on an M5x engine are M12x1.5x50, but that is because the dual mass flywheel hubs are really thick. S14 bolts are 22mm long, M20 bolts are 28mm long.

[nando]

is he the guy with the aluminum flywheel that had the bolts come loose? right.. I thought he was looking for bolts to use with an OEM flywheel.

[kroberts]

Yes, I'm the flywheel guy.

I'm trying to tie up as many loose ends as possible before I install the flywheel. Yes, I know about the online ETKs. The OEM bolt is 50mm long, it wont work with the aftermarket FW. The bolts that came with the kit could be about 4mm longer. The additional length will provide more surface area for the locktite to work with and more thread area to torque on I suppose. I think Bavauto was a little conservative with their bolts. I measured the depth of the crankshaft flange and the thickness of the flywheel and then subtracted 2mm to ensure I dont use too long a bolt.

[Massive Lee]

M12X1,5X22 8 11220616143 $2.01
M12X1,5X28 8 11221717840 $1.86
M12X1,5X50 8 11222243051 $2.34

that's all i could find

[chris4891]

i dont know your capabilities, but if it were me id just buy the oem flywheel bolts and turn them to proper length on a lathe. theyre readily available and doing so wont affect the strength of the remainder of the bolt.

[Massive Lee]

M12 x 1.5 x 35 socket head cap screws can easily be found from a specialized automotive bolt supplier. Problem is that they will often ask for a minimum or bulk purchase.

I purchase M12 x 1.5 Allen bolts (grade 12.9) in different lengths, but must purchase at least 50 units of each. Which is why I sometimes get invoices of $500 because I buy them in bulk and in different sizes.