Porsche 944 cam seal
replacement:
These directions assume that the
reader is familiar with timing belt removal, replacement and tensioning
techniques. If you are not familiar with
these skills, please understand them BEFORE beginning the following procedure!
For a larger version of each image below, simply click on the picture.
Replacement parts for this
procedure:
Camshaft mechanical seal:
999-113-282-40
Camshaft bearing large o-ring:
999-701-602-40
Small sealing ring: 928-105-184-00
Camshaft bolt: 999-510-022-08
Thin sleeve gasket: 944-105-321-00
1: Set engine to TDC, place car in
gear, and set parking brake.
2: Remove distributor cap
3: remove distributor rotor using
3mm allen bit or wrench
4: remove top portion of front
plastic timing cover
5: remove 3 10mm bolts holding
front cam gear cover in place.
6: remove 8mm bolt holding
distributor shaft in place pull shaft straight out.
7: while holding cam drive nut
with a large wrench use a 10M cheesehead bit in an
impact wrench to
loosen cam gear bolt inside, DO NOT allow cam gear to rotate!!
8: release tension on timing belt,
and slip off cam gear
9: remove cam bolt the rest of the
way, and remove cam drive nut and cam gear (both slide straight off).
10: Using a seal puller, push
point of hook into the seal and apply prying pressure to “tip” the old seal
out.
11: Coat the outside of the new
seal with heavy bearing grease, and using a seal installer tool, press new seal
in until flush with front lip of the housing.
If you wish to replace the cam
o-rings please continue, the rest of this procedure is more easily accomplished
if the cam tower is removed,
But
with care, can be done while still attached to the rest of the engine.
12: remove the camshaft woodruff
key with a pair of vise grips taking care not to deform the key.
13: remove the 3 10mm bolts
holding the rear cam cover in place
14: re-install cam bolt partially.
15: remove rear cover by pulling
on cover while gently tapping on cam bolt.
DO NOT
tap directly on the end of the camshaft, as it is easily distorted!! Sometimes,
twisting the rear cover a bit will help loosen it from the cam tower.
16: with the rear cover removed,
you can replace the large o-ring on the backside
of the rear cover. At this point the small sealing ring can
be removed with
a small screw driver, and new one installed. There should
also be a thin gasket
between the mating surfaces of the sleeve and the front lip
of the camshaft. Make sure the old gasket is removed before installing a replacement!!
17: At this point the front cam
bearing (found on the inside of the rear cover) can be inspected.
18: to re-assemble, slide rear cam
cover assembly onto camshaft, being sure to seat the
sleeve behind the
mechanical seal against the shoulder of the cam shaft (if this sleeve isn’t
seated all the way, the woodruff key can not be inserted!
19: re-install the 3 10mm bolts
through the rear cover into the cam tower.
20: replace woodruff key, cam gear
and drive nut.
21: making sure the timing mark
hasn’t slipped, replace cam belt, and apply enough tension to prevent cam gear
from turning.
22: install a NEW cam bolt and
torque to 32 ft lb while holding drive nut steady. If the cam gear
turns, there is the possibility of valve damage, Please use caution!!
23: re-insert rotor shaft and
re-install 8mm bolt using loctite 221.
24: re-check timing marks.
25: set tension of timing belt
26: replace distributor rotor and
apply loctite 221 to allen bolt.
27: replace front cam gear cover and
3 10mm bolts that hold it in place.
28: re-install distributor cap and
front plastic timing cover.