8v Tappets, checking and re-shimming

Full credit for this excellent write up goes to M7R, thanks Karl  


Time - 2-3 hours if a complete novice and working alone, sub 2 hours if you have a helper, this is not a hard job at all!

Tools needed;

Allen key (5mm I think) to undo the bolt on the side of cambelt cover,

10mm socket and ratchet with extender to undo the bolts holding down the rocker cover on the top of the engine.

Set of good quality metric feeler gauges,

vernier gauge,

Hazet 2574-1 to press the tappets down, (purchased via -http://stores.ebay.co.uk/Chrome-Trader-Tool-Shop - shop around as some places want to charge upward of ?70 each!!! I got both of mine for less than ?12 delivered!!)

Hazet 2599 - pliers to remove the shims, hard to do with out these. - again purchased via the above ebay shop.

magnet on a stick - this is to help get the shims out from under the cam, not 100% needed but I found it easier with it.

17mm socket and ratchet to cank over the engine.


Parts needed;

new shims - sizes wont be known untill the old ones have been measured.

rocker cover / cam cover (depending what you call it) cork gasket set (unless yours has been converted to run a re-usable mk3 one).


What to do.

1. make sure that the car is stone cold, then remove the bolt in the side of the cam belt cover, as shown bellow.



2. Undo the 10mm nuts that hold down the cam cover, and then lift clear the cam belt cover by pulling the bottom out to clear the stud the allen bolt screws on to, and the lifting upwards.(it needs a bit of wiggling but will go dont worry), now lift clear the cam cover.

3. Now using your 17mm socket and ratchet, slowly and gently crank over the engine so cam lobe number 1 is pointing straight up. (nose of the cam lobe should be inline with the middle of the cam cap, and dont forget the engine leans backwords, it must be in the middle otherise you will get a false reading).

4. Crack out the feeler gauges, and start measuring the gap between the cam and the top of the tappet, check against the limits listed here - http://www.isham-research.co.uk/quattro/wr_tappets_cold.html - print off and use the boxes to note the gaps down. NOTE THE ORDER OF THE VALVES! Exhaust, Inlet, Exhaust, Inlet, Inlet, Exhaust, Inlet, Exhaust

5. once measured, if out of tollerance follow this diagram - http://www.isham-research.co.uk/quattro/wr_tappets.html and pull the shim out, - the magnet on a stick is useful to grab the shim once its up and out of the seat.

6. Measure the thickness of the shim removed once cleaned with the verniers, and note on the sheet above. Use the table to work out the thickness of the new shim needed, (the come in 0.05mm steps as listed on the link above).

7. Move onto the next cam lobe, make sure its pointing straight up,and then repeat the process.

8. re-install the cam cover, fitting a new gasket if you have the older style cork one, and then refit the cam belt cover and bolt it all in place. - DO NOT FORGET THE EARTH WIRE THAT COMES OF THE BACK RIGHT HAND STUD as you look at it!!!

9. Order the new shims needed, which can be ordered from - http://www.vwspares.co.uk/g1other.php, try to get as close to the bottom of the tolerance box as you can with out going out of spec,

10. When the new shims arrive remove the cover as before, and install them in the correct place (as noted on your sheet you printed out) crank the engine over by hand a few times and then double check the clearnace of shim. run for 100miles or so and double check once bedded properly.

You have now checked and reshimmed your tappets and saved your self a ?180+ bill from a garage :wink: