Valve stem seal.

Message

ginge · #1 Post by **ginge** » Sat Dec 05, 2015 7:56 pm

Appears these have gone on my rear cylinder. Anybody done the job on the Falco, any tips/tricks?

Is this known to happen (bike has 48,000 miles) or should I be looking for other issues surrounding this?

I'm going to remove the cylinder head rather than trying to leave it on due to lack of tools and being able to have a look around inside more.

THanks for any help.

Wally · #2 Post by **Wally** » Sat Dec 05, 2015 8:23 pm

Have you made sure it is not the clutch cover gasket, the pipe from the clutch cover goes up to the rear cylinder manifold and can cause the same symptoms as it sucks up the engine oil from the clutch.

Mine went and it smoked like a steam train, I plulled the pipe off at the cover end and blanked it with a bolt and within 10 miles it had cleared.

Wally

ginge · #3 Post by **ginge** » Sat Dec 05, 2015 9:40 pm

Pretty sure it's the valve stem, will check the clutch cover just in case.

Looking down the inlet shows oil on the valve and the plugs were fowled by oil enough to make it fire only on one cylinder, suggests its most likely the valve stem seal sadly.

Aladinsaneuk · #4 Post by **Aladinsaneuk** » Sat Dec 05, 2015 9:42 pm

Try it and see would be a good option I think

Aladinsaneuk · #5 Post by **Aladinsaneuk** » Sat Dec 05, 2015 10:55 pm

Try it and see would be a good option I think

ginge · #6 Post by **ginge** » Mon Dec 07, 2015 8:31 pm

Should there be any oil at all between the diaphragm/gasket and the cover?

I have smearings of oil there and a small amount leaked out (talking millilitres, not lots) however I couldnt find any hole within the gasket, although it looks like it's seen better days so will replace it.

Putting a cotton bud in the pipe which goes from the cover to the throttle body showed there was oil in there too, although again stuck to the walls of the tube, nothing leaking out.

Wally · #7 Post by **Wally** » Mon Dec 07, 2015 11:32 pm

ginge wrote:Should there be any oil at all between the diaphragm/gasket and the cover?

In theory NO, and if it was leaking you probably wouldn't find much as it would get sucked up into the intake.

Leave the pipe off overnight to drain and then just blank the pipe and you can prove if the smoking is due to the diaphragm.

Wally

ginge · #8 Post by **ginge** » Tue Dec 08, 2015 7:56 pm

Never really noticed much smoking to be honest. Just went along fine with a bit of smoke on start up so I thought I'd overfilled it, stopped after my commute then on re-trying to start up it only worked on the front cylinder. Plugs out and they were pretty oily, quick look through the TB showed a lot of oil atop the valve, hence the likely seal diagnosis.

I need to do the clearances anyway so will take apart and have a look. The bike has 48k on it anyway so might be a good preventative measure for the future.

ginge · #9 Post by **ginge** » Wed Feb 17, 2016 2:19 pm

Finally getting round to doing this!

After changing the clutch gasket in the hope it may be that, and with some new spark plugs, the bike started up and ran great, for a few minutes before it started smoking again!

Anyway, on beggining dismantling the engine I have run in to a few problems. First the CCT retaining bolt/cover is stuck. Any ideas on removing it apart from heat and penetrating oil?

Secondly I jumped ahead and tried to remove the balance shaft counter weight, it will not budge. Is this threaded on or merely slid on? Tere was a fair amount of loctite on there so will try heating this as well.

Lastly on wiggling the rear header out it snapped (rather easily and looks fairly corroded) at the flange. Does anyone have the rear, or even front and rear headers they wish to sell? If not can anyone let me know if headers from an early RSV are a straight fit?

Thanks for any help.