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how to replace valve stem seals

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Jayman
Posts: 38
Joined: Thu Aug 03, 2006 9:21 am

how to replace valve stem seals

Post by Jayman »

Your normal tools, nothing exotic!
New valve stem seals $20-$30 from Auto pro, Repco,
Super Shit ect
A 14-17mm open ender spanner
A spare rocker rail so no matter if you damage it.
Normal and needle nose pliers.
Feeler guages to set valve clearance.
A magnetic pen would be a good idea.
And someone to keep you company.


First, remove all things over the rocker cover,
throtal cable, inlet plumbing, spark plugs + leads ect
ect.

Undo and remove the two 17mm nuts holding the rocker
cover down, (its a good idea to put all the nuts and
bolts you remove into a margarine container so you
don't miss place them), carefully remove the rocker
cover as so not to damage the two rubber bushes that
reside under the 17mm nuts, also take care with the
rubber rocker cover gasket.

You should now be able to clearly see the rocker
rail and rockers. There are 5 bolts which hold this
down, 2 of which are the bolts which hold the rocker
cover down. They should be 13mm jobs. Remove the two
spider retainers on both outside bolts. Undo all
5bolts in segments! Don't remove them completely one
at a time, as you might bend the rocker rail, undo
them in stages.

Take note of which way the rail sits on the engine
as it will need to go back on the same way.

If you don't have a spare rail to use, carefully
clean and remove all the rockers and spacers of the
rail. (MAKE ABSOLUTE SURE YOU CAREFULLY PLACE THESE
OUT SO THEY CAN BE PUT BACK ON THE EXACT SAME WAY THEY
CAME OFF) You will need to clean the rail as well as
the rockers, because the rockers won't easily slide
over oil crud build up. Using some insulation tape,
tape up the rail where the spanner will contact. Use
as much as you need as a $2 roll of tape can prevent
damage to a potentialy expensive engine part!

Using a 19mm socket on the harmonic balancer (crank
pully), turn the engine over till it's on TDC. With
the engine on TDC you will be able to do cylinders 1
and 4 both inlet and exhaust.

It's a good idea to plug the oil drain holes in the
head with a rag/s to prevent small bits falling into
the sump!!


Using two of the rail bolts, place the rail back
where it normaly sits, (minus the rocker gear of
cause), screw in the two bolts only 2 turns (choose
the two nearest bolt holes, one either side of the
spring), carfully slide the spanner under the rail and
over one of the spring retainers. Screw down the
bolts in turn by 2 - 3 turns at a time. The valve
will slowly push down till either the retainer
lostens against the valve colletts or the valve
touches the piston. Keep screwing down the bolts till
they are screwd all the way in.
With a magnet or a pair of needle nose pliers, remove
the colletts and place them in a safe place (pockets
are good, just don't miss-place them). Now you can
undo the bolts in the same fashion as you did them up.
The free lenght of the spring will be longer now that
it's not compressed so you may have a little tension
left when the bolts are at the end of their threads.

Remove the retainer and spring (there is also a
hardend steel washer that sits under the spring, make
doubly sure that this is in place before you reinstall
the spring!!!!!!!!!!!!!!), clean and put to one side.
Again take note of which way the spring sits as it
should go on one particular way. Using a flathead
screw-driver, pry off the old valve stem seal, you may
need to use a pair of pliers to remove it easily.

Now with the new seal, lubricate it with new oil,
push it over the top of the valve stem, and carefully
tap it home with a small hammer using a 13mm or so
socket that neatly fits over the top of the rubber
ring (but doesn't touch the valve) which forms the top
of the new seal. You can also use a 13mm ring spanner
or similar to do the same thing, just tap the shaft of
the spanner till the seal is pushed all the way down
to the base of the valve stem.

It all sounds quite complex as its hard to put into
words, but is very easy once you have done one. =7]

Make sure the washer is in place before you
re-install the spring (the right way up =7] ), place
the retainer over the valve, and compress the spring
in the same way as the first time around. Carefully
re-install the colletts, use a small screw driver to
centre the valve shaft in the retainer to make it
easier to push in the colletts. Once they are in
place, undo the bolts and the valve spring should be
back to origninal condition.

Repeat for opposite valve on that cylinder, and
opposite cylinder in the block. ie 1 and 4 2 and
3.

Once you have succesfuly done both valves on 1 and
4, turn the engine over till #2 and #3 are on TDC or
#1 is on BDC. You can check the height of the piston
in #2 or #3 by using a torch and looking down the
spark plug hole, turn engine over till piston is at
its heighest point.

Repeat valve spring process again.

Once all vavles are done, its time to re-install all
the rockers, spacers, and tension springs back onto
the rail. Re-install rail, and check and set valve
clearance. 11thou or .28mm note: this is the hot
clearance and will need to be re-checked when engine
is at operating temp!
Before you decide to criticize someone, walk a mile in there shoes.....

then your a mile away, and you have their shoes!!
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