valve wobble with new guides... anyone ever measure it ??

[Vincent Waldon]

Working on an AAZ head.... I've got 28 thou of valve wobble out of an allowable 55 so statistically I'm fine... but as usualit seems extreme and it got me thinking....

Has anyone ever measured the wobble of fresh valve guides ??

[subsonic]

I have a new AAZ up at Daves right now, and I know he has  one that came in the same box.  He has to take them apart for porting.  Give him a buzz.

[trev]

I've been winging it a little, as far as stuff like tolerances and measurements go. Really gotta get a Bentley book.

 I replaced the guides in my 1.6 head, to replace the very worn guides and very worn valve stems, on a low mileage head that had been rebuilt sometime about the year 2000. The grind of the valve  seats must have been done with a bent mandrel or just by a piss poor mechanic, as the seats were all very far off center. With the new guides in, there was a gap of about 30 thou visible, without the springs installed.
 The wear on the valve stems was very apparent, and caused by the valve seats pushing the head of the valves sideways. No wonder it smoked!

 I had access to a valve grinder, and whacked the seats to sit with the valves held in by gravity alone, and still seal.
 I had to ream the new guides to fit the new valves, and opened them up until the valve stem would move through the guide freely, not much more. I have about 4000 KM's on the engine since, and it seems well, so I guess it works at that. As I recall, I had just a bit of wiggle visible, but could not hear it click when I worked the valve stem back and forth.

 I dunno that my input counts, other than to demonstrate that tight works OK.

 Cheers
  Trev

[Vincent Waldon]

Thanks Trev... every bit of info helps... mine have more wobble than feels right but the bible says I'm only half-worn, so just looking for another vector.  

Now that you mention it VW valve guides are "ream to fit" so there may actually not be a common answer to "what does new wobble like".