1.9DG Rocker adjustment

[puddin]

I am getting a little confused...... Hope you can help

I have just finished replacing the water jacket seal on the left hand side (cylinders 3 & 4) of the engine. When I fired it backup it was somewhat lumpy and missing on 3. It then occurred that I should check the rocker adjustment, (On this side only)

Adjustment was attempted at the top of the compression stroke for each cylinder, I watched the inlet valve close and then used a rod through the plug hole to measure the piston position. I loosened the adjustment screw locking nuts and backed out the screws until the tension was released, which seemed to be around 2 complete turns for each rocker.

Now the confused bit....

I was expected to adjust the valve by turning the screw in 1 full turn from the point tension is felt on the screw, but any adjustment more than say 1/8th turn from tension leaves the valves open and compression is lost. The other thing I have noticed is a lack of "play" in the Inlet rockers even when the adjustment screw is backed right out, as though the rocker arm is resting on top of the spring. I couldn't inset a .015mm (.006in) gauge. Currently I have adjusted to around 1/16th turn from the point of tension and the engine seems to be running ok, however I remain concerned I cannot adjust as per the book.

If someone could shed some light on this it would be much appreciated.

Much appreciated!
Tony

[sarran1955]

Hello,

I've not got experience of the DG, but here goes.

(All rear engined petrol VW motors work on same principle)

Set your timing mark,(notch on pulley) to TDC, (about 11 o clock.) Paint it with Tippex and then do one 180 degrees opposite.

Take off dizzy cover...Is finger pointing to nr 1 plug .

If yes good. If no crank pulley clockwise 1 turn. Check.

When you reseat pushrods, it is very easy to get it wrong, in that the pushrod tip does not go into the dimple in the cam follower, so that the thing runs, but spits.

Oil out and rocker boxes off, look that all the tappet screws are about the same setting. If there is one that is wound way out look for badly seated pushrod

In valve position as above do Nr 1 cylinder tappets. Mechanical 0.3 mm hydraulic contact + 1 turn.

Now turn the engine 1/2 turn ANTI clockwise and do No 2 cylinder, (on the same side ha ha ), fit rocker box cover.

Turn engine 1/2 turn anticlockwise and do Nr 3 , and again for Nr 4.

refill with oil and re run engine, if you can hear spitting, you may need to repeat the procedure, cos you have a pushrod still wrong.

Hydraulic lifters will rattle for 20 mins before settling down, with a drain down of about a week.

If rattle continues, then reset tappets cold.

Once you have got your valve timing right, then you do ignition, then carbs mixture.

Cordialement,

[Mocki]

yep, pushrods not seated,
happens every bliddy time !

[puddin]

Thanks Guys,

Makes sense....Will re-check the seating...... again!



Happy to drain the oil, but is there a reason other than avoiding spillage?

Ta.

[weimarbus]

Thanks Guys,

Makes sense....Will re-check the seating...... again!



Happy to drain the oil, but is there a reason other than avoiding spillage?

Ta.

This is only needed to avoid spilling oil, I always jack up whichever side i'm working on and wait a few minutes for the oil to drain back down pushrod tubes. no need to drain engine

[CovKid]

Agree entirely. I always did that on bugs. Few rags - just to catch any dribbles.