Valve Adjustment
First, there are 2 basic ways of doing this, the way in the book, and the easy
(and VERY accurate) way. The official way is complicated and time consuming,
requiring you to be up and down several times, and looking for marks that may
not always be easily seen. In your case, the marks were even a bit
confusing. We'll start there.
Z1 is the mark between the letter "Z" and the number "1".
The other mark is of no consequence here. The next TDC mark is 120 degrees
along the circle, and the last mark is another 120 degrees after that.
Other marks may include the 3 timing marks and the "FE" mark, used to
set the MFI pump timing. You not only have to set the engine to each of
these TDC marks in turn, you have to do it TWICE, and you have to find which of
two possible cylinders you're on. Wiggle the valves, look at the rotor,
whatever. While you don't have to be EXACTLY on the mark, the closer you
are the better. On to the easy way, one regularly used on British and
Japanese cars, and Volvos as well. Works on EVERYTHING. You jack the
car up, just like the factory method. For our use, we're going to hook up
a starter button, or a wire with a switch in it, between the battery post on the
starter and terminal 51, the activator terminal. Hit the button a couple
of times to assure it works. You've drained the oil and removed the lower
valve covers. We'll worry about the upper ones later. Watching the #6
exhaust rocker (hey, you've gotta start somewhere, and it's right there next to
the starter), hit the starter button repeatedly in short bursts until that
rocker pad is on the highest point of the cam lobe. It's easy to see, but
you might want to go around twice the first time to help you see how it looks.
Move over to the other side, check and adjust the #3 exhaust valve, the one
straight across. Once you've done that, rock another valve open. Might as
well rock the #5 exhaust valve, it's the next in line and being organized has
its advantages here. Move across and check/set the #2 exhaust valve.
Do the other 4. Might want to go around twice, it's easy and it helps you
learn the feel and the procedure. Wipe down and clean the cam tower
surface, clean the covers, and install the cam covers over those nice new
gaskets. I like the gray ones. Use the new nuts and washers that come in
the kit.
Keep the car at a nice working height. Remove the top covers, leaving the
spark plugs in, and adjust the intake valves just like you did the exhaust
valves. Before you reinstall the covers and the nice new gaskets,
pull the plugs if you're going to replace them or do a compression test. Why did
we wait to do the plugs? For two reasons. First, with the plugs out
the engine turns over too fast to make it easy to stop it on the tip of the
lobe. Second, the plugs often shed carbon particles when they're removed
and those little bits fall into the gap of the open valve, causing a false
reading with the feeler gauge and making it difficult to get an accurate
adjustment. With the plugs out, there's no compression to blow those
little suckers out either. You get it back together, fire it up, and you
may have one (or more) horrendously loose valve(s), meaning you have to remove
that (or those) lower cover(s) and do it all over again. I'm not making
this up, BTW, we discussed it in P-car school, those 29 long years ago.
Same thing happens with the official technique as well.
This technique works with every cam grind, every engine. I use it on
Rabbits, 356s, 914s, 911s, everything. It's fast, really accurate, and
easy on the old back. After 30 years, the climbing up and down gets really
old, trust me. The clearance is ALWAYS exactly measured from the center of
the lowest point of the cam lobe, the base circle. You don't have to look
at those hard-to-see little lines (a definite plus on a 914/6!), you don't have
to look at the rotor, and you don't have to get up and down a thousand
times.
