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

you strip or otherwise wreck the bottom T-40 fastener, you will likely have to PULL THE
ENGINE to complete the job...'Nuff said.
Also, DO NOT use an El Cheapo T-40 driver bit either...if it comes out of a kit with a bazillion
other parts...uses different adapters to connect it to a plastic handle and says "made in China"...
GET THEM OUT OF THE WORK AREA..
Luckily, I went after the top T-40 first and the bit yielded under load and wrecked the head of the
T-40!! Because it was the TOP one I was able to grab it hard with a monster vise-grip and bust it
loose, after which it spun right out, no problem. My wife went out and got me a hardened,
impact grade T-40 x 3/8" ratchet drive bit. Made ALL the difference! Even after I cheezed up the
lower one a little, this quality bit grabbed it's target and brought the lower bolt out.
The Cam Sensor cover may be a bit gummed up with oil residue, so it may want to rotate a bit
instead of withdrawing from the head. Fine! Rotate it CCW a bit and you can tap the upper and
lower mtg. ears with a drift and light hammer alternately, until it walk's out. Set this aside.
Remove the 10mm bolt that retains the "shutter wheel" this is kinda like taking out a rotor from a
distributor housing. no problem. Set the shutter aside. Wipe out the pooled oil.
If you are smart you'll have a seal picker kit with many different parts to make many different
articulated angles...you will need them. If you are *me* you'll waste an hour sacrifice two
craftsman screwdrivers in a vise with an Acetylene torch, trying to fabricate the same thing. For
the record, the smaller one worked better. Use a Dremel tool or equiv. to de-burr and hone the
business end of this thing so as to not damgage any sealing surfaces.
Now is when you MUST have an inspection mirror. Get on back there, work carefully as you are
working a mirrored image. Hook that sucker under the garter spring + up behind the metal ring
and it pops right out real easy. Wipe the cavity out again and reinspect the sealing surfaces for
damage.
Lube up the new seal with... I dunno...I used heavy weight petrolatum..and ease it over the cam
shaft. Try and jam several fingers back there and push evenly on different point on the seal.
Make sure it doesn't cock in the bore. Stop and use your inspection mirror frequently to check it
is even. To bring it home...again, if your smart, you'll find a way to get a hold of Volvo Tool P/N
999-5450. It has a perfectly dimensioned steel cup with a hole in the back to put your cam shaft
shuter bolt thru temporarily to tighten the cup down and push the seal in to place. If you are me,
you'll hack a piece of nylon bar stock at work and while the prototype machinists are on break
and "borrow" a CNC Vertical Mill and fabricate same based on Seal dimensions and your best
guess from a picture in the service manual.
Anyway, my best guess was about .250" off, but before I ran off to get a longer bolt, I put both
hands on it and squeezed it against the head and ... "Whump" it popped right in. Check it again
with the mirror for even seating.
Put the shutter + 10mm bolt back in. Fit the tabs squarely in the milled slot on the end of the
cam. Tighten.
Clean the rim on the sensor cover and gently fit it over the shutter wheel being careful not to