[T3] valves

[Jim Adney]

On 25 May 2016 at 12:35, alluringeyewear at comcast.net wrote:

> Hello all!  I have a 1973 Fasty manual transmission with fuel injection.  I am about to remove the valve assembly to have a valve job done.  I seem to remember someone on the list some time ago mentioning a 4 angle grind. Is this what I should ask for and also what is the difference between that and a standard grind.  I have no idea what I should tell them other than do whatever it needs.  Thanks!  Doug "Leilani" 

There are several ways to grind the valves. The Original VW way was 
to put 3 different angles on the valve seat and grind the valves to a 
single angle which matched the middle angle on the seat. This is 
what's described in your manual.

If you add a second angle to the intake valves, inside the mating 
angle, that makes this a 4 angle job. This takes a bit more care to 
do correctly, but improves the breathing a bit.

The cheap valve grind doesn't bother with anything except the middle 
angle on the seat and maybe the single angle on the valve.

If I'm doing a valve job, here's what I do:

Disassemble and clean the head.

Check the guides and replace any that have significant wear. Check 
with a new valve; a new valve should have just a trace of play in the 
guide. New guides may need to be reamed.

Check the springs and replace any that don't have sufficient force.

Clean and reuse the intake valves if they are still the OE VW ones. 
Touch up the angle and add the new inner angle.

Replace the exhaust valves with VW, TRW or ATe new ones.

For the best overall job, check out the Bill Fisher book, "How to Hot 
Rod the VW Engine" and shim each spring to the height he mentions in 
there.

Replace any missing rubber "seal" rings around each valve stem, under 
the springs. Oil the valve stems as you assemble the parts.

Many shops won't want to do some of these steps.

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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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