View topic: 1.1 engine valve stem seal replacement guide

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A guide on how to replace your valve stem seals without removing the cylinder head.

Bought my golf last year, a 1.1 Formel E made in 1981. Interior and exterior were pretty good, it just needed some tinkering with the electrics and it also smoked a considerable amount.

I was told that it calmed down once the engine warmed up and was probably the valve stem seals. These are the symptoms i noticed after driving it around for a few weeks.

- lots of smoke on startup, reduced somewhat once warm but still some smoke idling.
- considerable smoke seen when accelerating from junction.
- little or no smoke when decelerating or driving along at normal speed.

I'd like to share my experience for anyone wishing to do the same. Car was on my drive for approx 3 weeks, due to working on it mainly evenings and having to wait for parts to arrive.

This method is sometimes called "the rope trick" and works by stuffing rope into the cylinders to prevent the valve from dropping due to gravity when the valve spring is removed.

This is what the engine bay looked like before i began to work on her. As you can see there's lots of space which makes it a great car to work on.

Parts Required:

Valve Spring Compressor (I used a Sealey V160, worked alright but was a bit fiddly)
Valve Stem Seal Plyers (cheap enough on ebay)
Decent Socket Set
4m Nylon Rope (6mm)
8 Valve Stem Seals (vw heritage ones worked for me)

I followed the haynes manual, and also some of this guide which was quite useful http://forum.205gtidrivers.com/index.php?showtopic=136218

You may not necessarily have to follow th exact order but the following things have to do done before tackling the valve seals themselves.

- Remove the spark plugs (easy enough)

- Remove the timing belt. To do this you will have to first remove the timing belt cover. In addition I found that the alternator belt had to come off.
The timing belt tension is altered by removing the 3 bolts holding the water pump to the engine, and rotating the entire pump around. Put a bucket underneath to collect any water that gushes out when you do this step.

- Once the timing belt is off you can begin to take a look at the cylinder head. Remove the cylinder head cover if you havn't done so already. You'll need to take the fuel pump off which is at the top left of the cylinder head.

- Remove the distributor (mark the position of the distributor arm when the first valve is at its lowest point to aid timing restoration)

- Take the gear wheel off the left end of the camshaft.

- Next step is to remove the rocker arm clips and then the rocker arms, this leaves just the camshaft to remove

- Pull out the camshaft from left to right and expose the valve springs.

[All my parts removed]

That was the easy bit, now the tricky bit is actually replacing the stem-seals themselves. First we need to support the valves by dropping our rope into the first cylinder.

You will need to find your nylon rope, put a mark exactly in the middle of the rope.

This marks 2m of the rope, so you know where to stop.

Now drop a rod down the first spark plug hole, and rotate the crankshaft. Watch the rod go up and down as the space piston rises and falls. You want to stop it at the lowest position so that you can feed the rope in. If you are unfamiliar with how pistons and valves work then take a look at the diagram below. For each cylinder, 1 valve lets the fuel and air mixture in, whilst the other lets the exhaust out. The idea behind the "rope trick" is to fill the space with rope so as to support the valves and prevent them from falling into the block. So starting lowering the rope into the spark plug hole, keep doing this until you reach the marker, 2m should be sufficient. Then turn the crankshaft until it feels tight, this make sure it is tightly pressed up against the bottom of the valve.

Now we start replacing the stem seals on valves 1 and 2.

You need to remove the spring to replace the seals. To do this you need to compress the spring and then remove the collecs that hold it all in place. This can be really tricky, and be careful not to loose the collets. ( I accidentally dropped one of mine down an oil passage, dont make the same mistake)

[Compressing the spring]

Try and separate the valve stem seal with the pliers with a kind of rocking motion to loosen it up. Once the spring is off, take all the sections away and give them a clean up.

[Parts Removed]

Parts removed should include in the spring, spring seat (and valve seal), spring top and 2 collets.

[ Cylinder Head with spring removed ]

Once it is all cleaned up you can now put on your new seal.

[ Old seal vs New Seal]

The haynes manual describes a plastic tube that protects the inside of the stem seal from getting damaged when inserting over the valve. I made a makeshift one out of a bit of plastic i found lying around. I placed this inside the stem seal and then put it over the top of the stem seal. Then slid the seal down into place.

[ Makeshift protector ]

Make sure the seal is firmly in place, do this by finding a socket of the right dimensions and press down on it until it seems firm.

[Pressing down]

Once the seal is in place you can put the spring back together. You will need to compress the spring again. Getting the collets back on is really tricky, you may need help from somebody to compress the spring here.

Repeat the same procedure for valve number 2.

Then do the same for valves 3 & 4, 5& 6 , 7 & 8. Remembering to move the nylon rope onto the next cylinder at each stage.

Finally put it all back together is more or less the reverse of taking it apart. Remember to align the notches for your distributor and your timing belt in order to get the timing back.
______

[Put it back together]

Thankyou for reading my quick guide. If you have any questions please don't hesitate to ask.

Here's a pic of what my car looks like today.
(I really need to replace those wheels)