944 Front Engine Seals
Replacing Front Seals
A set of engine seals (front only) costs about $40. It is generally well worth the little expense and time to go ahead and replace the seals if you're "in the area" replacing a water pump. You may need more than seals though, the oil pump sleeve and the balance shaft spacers will occasionally be worn too. It is difficult to know this until you have the parts separated for inspection. This situation often means that the job will take several days while needed parts are first determined and then ordered/shipped.
Here's a tip for removing the crankshaft key, a sharp pair of dykes - usually works. In a worst case situation, I've had to mig-weld With a small dot onto the sides of the key so that I could grip it with pliers. With the key out, I can remove the old seal. This old trick works as well as any seal removing tool, just be sure to drive the screw in near the outer edge of the seal. Caution, take care to not allow the screw to touch the crankshaft - scratching the crankshaft would be really bad.
Here are the removed parts from the crankshaft (machine washer not shown). Inspect the oil drive sleeve for a groove (worn into it by the lip of the seal). If you can catch your fingernail on the groove, then it should be replaced. The new seal gets tapped into place with a large socket.
Balance shaft keys are gently tapped out - the half moon shape makes them easy to get out. These small parts are easily lost, so beware. Each of the two balance shaft front covers are removed to the workbench.
There are several small parts used to mount the power steering pump, this (above) dirty photo is to remind me which small parts go where. This is a good time to spend a few minutes cleaning up the front of the engine. Some spray brake cleaner and a small brush can do wonders, but beware of the fumes! I always do better work with the grease and grime out of the way.
You can see the socket that I used to drive the spacer (sometimes referred to as a sleeve) & seal from the back side of the cover. Once I'm satisfied with the condition of the spacer and the bearings, I simply insert the spacer into the new seal and press the new seal into the front cover. A simple bench vise is perfect for doing this.
Special note: the two balance cover seals look similar but are actually different. There is a right and a left and can be distinguished by looking at the ridges on the inner surface of the seal. The ridges direct the oil back into the engine. They must be re-installed carefully. The lower balance shaft cover is known to be problematic and must be installed by bringing up the torque evenly. Always check the shafts to be free to rotate after installation.
All that is left to do is replace the onion skins, these are small Mylar seals, similar in shape to very thin washer with a diameter roughly equal to a US quarter; nicknamed: onion skin seal.
With those in place we can re-attach the balance shaft front covers and begin re-assembling the engine.
Note: some will observe that I did not "do" the cam seals. Frankly I don't routinely do the cam seals because they very seldom leak and its a real pain to get the cam gear off.
If you must "go there": here is a photo of the various parts. Expect to have to drill the head off of the long cam bolt using a 3/8 bit. So best to have a new bolt on hand.
Hint: use thread locker on the tiny bolt used to secure the ignition rotor. That bolt tends to com loose and may strand you.
Photo courtesy of "Granite 944"