Replacing stem oil seals in situ ?

[MK3]

My MK3 Spit hasn't run on the road for about 10 years, which is soon to be corrected as I got it through the MOT last week :)

But I've noticed a reasonable amount of smoke coming out the exhaust after it's been at idle and then revved up. I'm probably not going to do anything about it for a while until I've put some miles on it but if it's oil seeping past the inlet valves, I believe Canleys stock valve stem oil seals to cure this:

http://www.canleyclassics.com/searchforapart/?desc=&ptno=HR631

I'd prefer not to have to remove the cylinder head so did a quick google and came across this ..

Quote:

If you've got a adapter for the plug hole , compressed air will hold the valve closed . But is not foolproof , you slip and the valve can drop . Foolproof method is to bring the cylinder almost to TDC and feed some small dia. rope into plug hole then bring the piston up further to compress the rope against the valves lightly by hand ! only ! . Then just back the piston back down a little to get the rope back out , After you've changed seals or springs and put your retainers back on and have removed the tool , give the valve stem tip a smack with a small ball peen hammer to make sure the retainers are seated , Don't beat it , just a sharp smack will do
Do one cylinder at a time and you can make a quick job of it .
Used to get paid 8hrs labor to replace valve seals in 4cyl Camry's , got it down to a 45 min. project ...

Has anyone replaced valve springs / added stem seals while the head was still on the engine using either compressed air or this rope trick ?

[Dannyb]

I have done this on a single cylinder motorbike no problems

[Nick Jones]

They don't have stem seals as standard.  It is possible to fit stem seals to standard guides, but only if you are using single valve springs.  I tried this on my PI......

http://sideways-technologies.co.uk/forums/index.php/topic/5167-nick-mk2-pi/page-3  (post #41 on)

Didn't have much effect because (as it turned out) most of the oil was getting past the piston rings via rust pits in the bores.

Note that as standard, when all the valve gear is in good shape, not much oil gets to the top end and not much is needed.  Once the rocker shaft/rockers wear then a bit more oil gets up there, though still not very much.  This increases to a flood if an external rocker feed pipe is fitted - and in that case you have about the only scenario in which stems seals are going to make much difference.

Cheers

Nick

[Velocita Rosso]

I`v never had stem seals on at all
As Nick says there should not really be a `bath` where the oil feeds over the top of the stems

[esxefi]

I would run it for a while first as you say.

also worth checking the crankcase breather hoses as oil can sit in these and be sucked into the engine when it gets hot especially as it has been sitting around for a long time.

[MK3]

esxefi wrote:

I would run it for a while first as you say.

also worth checking the crankcase breather hoses as oil can sit in these and be sucked into the engine when it gets hot especially as it has been sitting around for a long time.

Hi, thanks, I can only see one short hose from the rocker cover to a large valve on top of the inlet manifold. I replaced that one. Are there others I should check ?

It's a 1296cc engine, single spring valves

[Velocita Rosso]

4277 wrote:

large valve on top of the inlet manifold.

The clip should come off revealing a rubber diaphragm which needs cleaning regularly

[MK3]

Hi, yes that's all been cleaned and the diaphragm is good