Headgasket 125LD Mark2

[jdevane5]

So getting my scoot ready for this year and looks like I have a blown headgasket.
Removed the cylinder hear to find no gasket and just a gasket sealant used.

So ordered new gasket which tuned up today which is Ali and about 1mm thick.

Would you use sealant with the gasket? The surfaces are not too bad on the head or barrel.

[jbcollier]

Myself? I would dress the cylinder head with some fine sandpaper on a piece of glass and then assemble it with a smear of high temp silicone sealer.

[jdevane5]

Interesting...so drop the gasket...
I will clean up both surfaces with wet/dry and use a bit of engineers blue to see any high / low spots on both surfaces then seal the joint and do a stepped gradual torque pattern.

Cheers JC

[hullygully]

I'd check the head squish with & without the gasket first before sealing up bud

[jbcollier]

Unless the engine is modified, there's no squish. The piston does not go all the way to the top and it has a "bathtub" combustion chamber.

I modified mine with a stroker crank, alloy barrel and a modified 125DL cylinder head. I have a proper squish band and it runs and starts quite a bit better than stock.

[jdevane5]

Cleaned both surfaces and sealed, just started torque up in stages on the cyl head studs, got to 10Nm and one of the studs snapped at the nut...I usually tighten to 20Nm.
I had replaced std nut and flat washer with a M6 flange nut but I think the clamping force may be too much so reverting back to original now. Four new studs ordered..