PD injector preload

[mickel2]

Hi, can someone give me an idiots guide to setting up the injector preloads on my AVB pd engine. I am a little confused by a guide I have got for it, on an Audi engine. Its the bit about whether the rocker should be compressing the injector down to adjust the adjuster back 180 degrees. or as in a tappet adjustment the rocker should be floating to adjust it. Thanks.

[zollaf]

as you say, tighten the rocker down until you feel the injector bottom out, then back it off. there is no gap like a tappet. once you try one you will see what the score is with them.

[stevegrass777]

The screws used to be flat head so you would screw the screw in until the stop then back off one flat of the screw driver which is 180∅.(I am talking about Cummings unit injectors where they used this system well before vw maybe 15 years before,but vw use a Allen key but its still 180∅)
But the injector rocker has to be at full travel first so to ensure this use a dial indecator.

[zollaf]

to be fair the cam has a very long duration of being fully open (injector pressed down), so if you put it half way between starting to open and starting to close, you will be close enough if you don't have a dti.

[mickel2]

Thanks, I do have a dial indicator, will give it a go. Mike.