Thread: 110 V8 white puffs on gear change

Valve guides worn or more likley the stem seals have hardened up with age.

Its probably worthwhile to have the guides machined for the later type of seals.

Only do that with the inlet side and only after you inspect the guides for wear. You can sometimes get away with knurling the guides or having an insert placed in them. LR make out the guides are easy to change. Ha!

Regards Philip A

Originally Posted by PhilipA

Valve guides worn or more likley the stem seals have hardened up with age.

Its probably worthwhile to have the guides machined for the later type of seals.

Only do that with the inlet side and only after you inspect the guides for wear. You can sometimes get away with knurling the guides or having an insert placed in them. LR make out the guides are easy to change. Ha!

Regards Philip A

Thank you Philip,

I am in the process of changing the stem seals as a first step, if it doesn't cure the problem than I will move to changing the valve guides as you recommended.

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Someone recommended placing a stem seal on the exhaust valve as well, do you think that it can help solving the problem?

Thank you

Patrick

I think it is unlikely to be the valve guides or seals .
If is burning oil the smoke will be black. I suggest that it is possibly the start of a head gasket problem and that water and glycol is getting into the combustion chamber, alternatively your brake master and booster could be letting brake fluid in via the vacuum line.

I hope you find the cause and are able to fix it.

Ian
Bittern

If is burning oil the smoke will be black.

Huh? Not where I come from.

Re exhaust valve guides.
There has always been debate about this. I always did not fit seals on the exhaust. The thing that causes the puff of smoke is the high vacuum in the inlet manifold as you lift off to change gear caused by the throttle closing. This does not apply to the exhaust and some argue that to have seals on the exhaust encourages carbon fouling of the exhaust valve and valve seizing.

Regards Philip A

White smoke..........coolant in combustion chamber or brake fluid via brake booster.
Brake fluid especially makes white smoke.

Valve guides and or seals tends to be blue smoke on a trailing throttle, like putting your foot down after going down a long hill.........blue smoke

Brake fluid makes white smoke with a certain odor about it, brake application or gear changes tend to cause the white smoke.
Coolant in the combustion chamber tends to be a pale white smoke at most times.....but specially when cold........look for gradual coolant lost, water in engine oil etc.