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Matty86
08-03-2007, 21:33
Out today driving over Dartmoor and I noticed a lot of blue smoke coming out of the exhaust on over run.

The oil level has gone down a little bit

If i accelerate hard in 2nd then at about 6500ish rpm lift off slightly and just let it run as it slows me down I get the smoke...

No smoke any other times.

Rocker cover and gasket have just been changed.

it's white smoke (i.e. water) that means hgf ain't it? what's causing this? :(
Coops
08-03-2007, 21:36
am confused, thread title says blue smoke which is either valve stem seals or piston rings

but in thread itself you say its white smoke? :?
Coops
08-03-2007, 21:37
oh wait i think i get ya, you mean its white for hgf so whats blue!
Matty86
08-03-2007, 21:40
yeh, that's the one :D

is changing the seals a pig of a job?
Allan
08-03-2007, 23:06
wouldnt worry about it :D

mine used to do it all time on a hard thrash, just top the oil up ;D
Coops
08-03-2007, 23:08
as said, so long as its not excessive just top up oil when u need and dont worry bout it, or avoid the situation that causes it! :lol:
Andyvalver
08-03-2007, 23:14
Mine does it a bit on overun. If you let it overun and then dip the clutch and rev the nuts off it it does it too lol. Doesnt do it on hard acceleration though. It will be the valver guide seals, nothin to worry about really imo. Mines been doin it for a while and its on 162k now 8)

think of it as a James Bond style smoke screen for when your racing other cars :lol:
nyk
08-03-2007, 23:14
just a bit or bore wash. Dont worry about it unless its like plooms.

:)
Swervin_Mervin
08-03-2007, 23:21
ULF never smoked. Fitted decat last week and took it for a spin. Looked like a bonfire on overrun! :P

Don't worry about it.
DaveH
08-03-2007, 23:27
Its when it does it when you boot it that you have to worry- like mine :lol:
stan
08-03-2007, 23:30
just a bit or bore wash. Dont worry about it unless its like plooms.

:)

what lol


just sounds like the usual stem seal leakage...wouldnt worry aboutit mate.
Matty86
08-03-2007, 23:31
its a fair bit of smoke

my mate was tailing me on his bike with a bullet cam, ill get a vid up :D

as long as its 'fairly' common then :D

and it doesn't do it on acceleration :D
DaveH
08-03-2007, 23:36
Id say if you can put up with it and it doesnt go through oil too much then leave it as its a fair bit of work to strip the head and replace the seals, all depends on you really.
stan
08-03-2007, 23:49
Theres liekly a bit of play in the guides also.
nyk
08-03-2007, 23:50
just a bit or bore wash. Dont worry about it unless its like plooms.

:)

what lol


just sounds like the usual stem seal leakage...wouldnt worry aboutit mate.

as in bit of oil passing the rings I meant -not fuel.

Could also be worn valve stem oils seals.
stan
08-03-2007, 23:56
given its not doing it constantly or even under load...and it IS doing it under over-run, I would defo say guides/stem seals.
Matty86
09-03-2007, 00:47
cheers guys

I'm gonna leave it

it's sucked up far too much of my money recently! :(
J o n
09-03-2007, 10:15
every decat'd Willy or Valver I have seen have blue smoke come out the back on overrun, mine did it on both engines.
Matty86
09-03-2007, 11:17
mines be decatted for a while (no mid box either)

first time i've noticed the smoke :o


but if its normal....
Imperial_16v
09-03-2007, 16:52
Mine did this once (Valver with decat). Just a little bit came out on the over-run when I was giving it some hard revs on the driveway. (I had just fitted my IK so I wanted to hear her roar). lol. :lol:

It was only a little bit, so I'm not bothered either. :)
BenR
09-03-2007, 22:12
Not normally stem seals, they tend to weep white because they burn coarsely in the exhaust manifold.

Blue is just a normal mixture of the fuel on overrun and high inlet manifold vacuum possibly pulling oil vapours and weeping past the rings.

Its normal and nothing to worry about unless its heavy.