Oil leakage around exhaust manifold / cylinder stub

[victor]

Hi all experts,

I've black oil slowly bubbling out from around between the exhaust manifold clamp and the stub on the cylinder.

The exhaust cannot be fitted any better with only about 2-3mm of the stub visible between the clamp and the cylinder.

The clamp is tightened to correct torque and then tightened even more.

When the engine is running, small black oil bubbles are created between the stub and the manifold. They then burst or drip off and the fan sprays them over the gear change cables and the kickstart arm.

Can anything be done to avoid this as it's annoying having to wipe it off constantly to keep the scoot clean?

This doesnt happen on my lambretta but on the other hand it has a quite large gasket on the exhaust manifold which the Vespa doesnt...

Would appreciate any ideas - cheers V

[gaz_powell]

cast iron stub ?

often the stub and exhaust are not a perfect fit

just use some heat resistant silicon or an exhaust paste on assemble

if its ali you shouldn`t be using a clamp only springs - again with a sealant

[coaster]

I agree with Gaz, I use Hermatite High Temperature Silcon, it does burn through eventually but should help.

[Polossi220]

Sip do a gasket set
Art.No.
13014000
Around £6
Mate fitted it to his polini sip pipe combo worked a treat

[victor]

The sip gasket set wont fit the SS stub, but I do have some high temperature instant silicon gasket lying around which I used for the cylinder head, it's transparent. Do you think this would be suitable and how do I avoid gluing the exhaust to the cylinder stub....?

[coaster]

The sip gasket set wont fit the SS stub, but I do have some high temperature instant silicon gasket lying around which I used for the cylinder head, it's transparent. Do you think this would be suitable and how do I avoid gluing the exhaust to the cylinder stub....?

I'd give the silicon you have a go but don't worry about 'glueing' the stub on permanently, that ain't going to happen with all that heat and oiul about.