Valve stem seals

[pskipper]

Hi,

On the Bull Motif website they show the cup seals and state that they are an improved replacement for the o-rings, is this correct or should both be fitted?

Thanks,

Philip

[alex_holden]

I fit both, but I only put the cup seals on the inlet valves (the exhausts won't suck oil in anyway).

[popleycrew]

Hi, i have just done my valve stem seals with just 'o' rings. If you are getting the cup seals make sure on the valve guide you have a ridge for seals to sit on otherwise in time they will come off.

[MarkyB]

I expect they would still help, working like umbrellas over the valve guides.

[alex_holden]

They don't seem to come off, even without a lip. The new guides you can buy from the suppliers don't have a lip.

[bmcecosse]

If you fit both - you 'may' starve the valve stem of oil to the point it seizes! Just fit the cup seals - to the inlets only.