Hi

I am currently trying to set valve clearance on a beetle. I have a 1600 twin port engine. Trying to work out the gap I need.

The manual says to look for short or long studs on the rocker arm support to determine which clearance to use. Can anyone help me with this?

Also, I have a drive pulley with three marks on it. Which one is TDC etc? On the face of the pulley (closest to the rear of the car) are two marks - one bigger thean the other and the other one is only slightly off it to the right. The third mark is on the back of the pulley and a fair way off the other two marks. Any ideas?

Thanks.
David

ok so i'm assuming you're new to this game.

The short/long rocker stud thing only applies to 1200 40hp engines as the studs for the rockers had problems with pulling out, as you stated you have a 1600 this shouldnt concern you at all.

Ok the procedure for adjusting valves is pretty easy once you've done it a couple of times.

1. Take the distributor cap off the distributor and rotate the engine until the distributor rotor is pointing at the notch that should be on your distributor rim.

2. Now you have to determine Top Dead Centre, pointing the distributor at the notch puts it in the firing position for Cylinder #1. On the pulley you say there are 2 marks, one on the left should be TDC and the other should be 7.5 deg Before Top Dead Centre. These markings should be correct, so line up TDC with the crack in the crankcase. You can make sure it's TDC by removing a spark plug and inserting a pencil or a wooden dowel in the hole and feeling when the piston reaches its highest point whilst you turn the engine over.

3. Once you have done this remove the valve cover on the #1/#2 side. Get out the feeler gauge and pull out the 0.006 inch feeler blade. Set the valve clearance by pushing down on the rocker arm (on the bit where there is a serration) and shoving the feeler blade in and adjusting the screw until it slides through with a slight drag on it. Do this for both valves.

Before you adjust anything see what clearance the valves are already at, be wary of an exhaust valve which has to little clearance as this means it may have been overheated and has stretched permanently. Soon enough the valve will just break off and say hello to mr piston and it will cost you much much more than a valve job.

4. Once you have adjusted #1, rotate the pulley anti-clockwise 180deg, there should be a marking there, or you can just mark it yourself with the pencil/dowel in the spark plug trick. when its turned 180 deg anticlockwise it is in firing position for cylinder #2. After you have adjusted #2, rotate 180 deg backwards and its in firing position for #3, and so on for cylinder 4.

Remember to only adjust the valves when the engine is dead cold. Don't remove or thread in spark plugs on a hot engine as it may stuff up the soft aluminium thread in the cylinder head.

good luck

Yes the procedure sounds complicated, but it isn't really. Once you try it a few times, there's nothing to it.

VW used to specify 0.004" for valve clearances, with a few exceptions on some motors (which is why your manual asks you about long or short studs). However in the late 1970s they put out a service bulletin saying all valves could be set at 0.006". So use that, and don't worry about it.

If you have metric feeler gauges, 0.006" is 0.15mm.

Thanks guys,

I followed those directions and I think I got it pretty right. Thanks for your help. I was a bit stuck working out how the cylinders were numbered but once I got that it made sense.

Found I need to replace the vacuum advance unit - would account for (as well as the timing being way out) the backfiring that has been occurring.

Does anyone know how much one of these is worth roughly?

David

mmm i think the vacumn canisters aren't too dear, but if you're strapped for cash you can try to get a complete used distributor for cheap with a working vacumn can.

try our sponsor www.mickmotors.com.au

Hmmm, the vac cans varied a bit over the years; but a number of members have 009s or SVDAs - try a post here if you get stuck (I myself might have an appropriate dizzy available for postage in a few weeks.)

Hi

I reckon the easiest way if you have a manual car is to jack up the car, let the handbrake off, put it in 4th gear, lay under the car, put your foot on the wheel on one side of the car and try to keep it in place, then turn the wheel with your hand, which will turn the motor over, turn motor over until you have the valves are rocking on a cylinder, repeat the process until you have set all valves, if your a big jessie or a nancy boy remove the plugs 1st.

BTW 6 thou is a 1/4 turn on the rocker screw on 1300, 1500 & 1600 motors.

1302Steve

but Steve...(whinge whinge sound)...
one likes to be acurate and write down the existing valve clearances, for later reference, and preventative maintenance,
one does................you thinks not?