Volvo Maintenance Hints for 7xx/9xx - Bill Garland's Nuclear ...

tic mark on the distributor lip (subtle but very informative, no one ever mentions this trick) and
the crank guide slot is exactly on the relief mark on the block at TDC on the crank. This last one
can take time to find and appreciate.
I suggest removing the old belt with a sharp knife to avoid disturbing the position of any pulleys.
Before removing the old belt, compress the spring on the tensioner and insert an appropriate pin
in the hole in the rod inside the spring to retain it in the compressed position. Remove the pin
after the new belt is installed. [Don Foster] You
know, of course, to first squeeze the tensioner back
and lock the nut to hold it. Once the belt's in place
release the lock nut so the tensioner presses against
the belt. Tap it lightly -- this takes up the slack -- and
lock the tensioner nut (37 lb.-ft).
[Tip from Steve Seekins] Rotate crank so that mark is Holding the tensioner back
about 9:00. Then put on belt - double marks straddle
the crank mark (notch on outer plate). - be sure to get
it right. Then put belt on intermediate shaft sprocket -
line up mark and clip with a medium binder clip or one
of those plastic woodworking spring clips. Do the
same for the cam sprocket - you may need to use a
wrench to turn the cam so the mark lines up with
index mark on the belt - if the marks will not line up,
you likely have the belt backwards - all three will only line up one way. Do not worry about
rotating components individually - this is a non-interference engine. Before you remove the
clips, double check to make sure that the crank mark is lined up with belt marks. Release the
tension roller, rotate crank 2X clockwise with wrench and tighten tension roller. Replace covers,
pulley, belts, fan and you are finished. After a couple of hundred miles, remove rubber plug in
timing cover, loosen tension roller and rotate crank CW 2X again and tighten. Don't touch it
again for 50k miles.
Indexing the Timing Belt Markings. [Tip from Randy] Lets assume the belt that is currently on
there is correct. All you want to do is replace it with a new belt- you want all the orientations to
remain the same. Mark the current belt in some permanent way in relation to the gear. If the
timing marks on the gears match up with an individual cog on the belt that will be perfect- if they
don't you might have to make your own marks on the gear (fingernail polish comes to mind).
The point is once you have the belt indexed to the gear arrangement you can easily remove it
and you could put it right back on and be confident of getting it correct because you have the
index marks on both the belt and the gears. So all you have to do is take the indexed belt off
and carefully transfer your index marks on the old belt to the new one. Do this very carefully and
be sure you match cog for cog as you move around the belt and mark the new belt exactly like
the old one. BE CAREFUL to double-check the markings before going back to put it on. You
might want to mark the front of the belt for reference in relation to the front of new belt. Some
belts are already marked when new, but I always mark my own. [Response 2: Paul Kane] The
intermediate shaft is no longer important. I use white-out (correction fluid) to mark stuff. The
Cam mark is at 12:00, the notch on the belt guide on the crank is at about 10:30 and IS the cast
mark on the block. BTW the notch in the center pulley aligns with the pointer on the lower cover.