FredR

Worse things can happen on a 928. At least you have done most of this activity previously.

Just remember if you remove the cam wheel you then have to re-time the cams. You could make some indexing marks relative to the three threaded holes for the rotor arm screws that would probably get you accurate relative to where you currently are within about +/-2 degrees. But if you are going to play around with this kit just get hold of Ken's 32VR kit and bumpstick - cam timing is then a doddle. I recently changed over my cam sprockets and the cam timing part of it took me about 10 minutes.

UKKid35

Surely this is more important than a duff Hall Sensor?

Mattman928

Does anyone have a cam timing kit I can borrow?
Between the belt and the hall sensor it makes sense to pull everything of again. Btw should I do the driver side sensor also?

Mrmerlin

the only hall sensor for the cams is on the 1-4 cam pulley

Mattman928

It took using an easy out to destructively remove the sensor bolts

Mattman928

Now that I have stripped the allen bolts that hold the current Hall Sensor, can I replace with any bolt (e.g. a steel bolt)? I am thinking about switching to a Hex head (must check if there is enough clearance).

Now I am off to inspect the timing belt

soontobered84

Mattman,

Now that you have been initiated into the Hall sensor removal and replacement school, I have an additional question that I did not see previously in the thread:

Did you remove or loosen the cam gears during the water pump/timing belt replacement?

If you did remove/replace/or loosen the cam gears, you would need to retime the cams.

Just a thought.

Mattman928

not sure I have been initiated, I've definitely pledged and gone through hell week. LOL

I did not touch the cams at all comma and I verified again now that I have it disassembled that the v-notch in the on the back of the cam gear is perfectly lined up with the notch on the back of the casing.

Mattman928

After destroying the allen bolts from the Hall Sensor, I needed to find replacements.

I found the following at home depot but it's basic steel. I know this is a dissimilar metal to the back of the housings. Can I use these and which antisieze should I use, or can I use any of them. I think I have the Copper and the Aluminum.

Mattman928

I think I answered my own question. From the article below they talk about two challenges with steel bolts in Magnesium; 1 galvanic corrosion (but they like aluminium fasteners with low copper, so I know which anti seize to use )

They also talk about clamping force since Magnesium has twice the thermal expansion of steel. I think the bolts that come from Porsche are Zinc coated Steel, so i should be okay.

_______________________________




Due to the difference in electrochemical properties of
steel versus magnesium, galvanic corrosion is a big threat
for joining magnesium components with steel fasteners
in a corrosive environment (Figure 3). Typical surface
coatings available for galvanic isolation are not effective.
Figure 1. KAMAX aluminum fasteners.
Figure 3. Test results of galvanic corrossion: steel, aluminum and plastic
bolts on magnesium alloy AZ91 (after 288 hours salt spray test).
Figure 2. BMW NG6 engine (courtesy: BMW AG).

LIGHT METAL AGE, APRIL 2005 3
Electroplated zinc and zinc alloys in combination with
isolating sealers show improved corrosion resistance in
laboratory tests. However, the effectiveness of these coatings
is limited to porosity and damage to the surface.
Surface damage is usually caused during handling of
parts and during assembly.
Fasteners made out of 6000 series aluminum alloys,
with a copper content limited to 1%, show greatly
improved galvanic corrosion resistance, with usual die
casting magnesium alloys (AZ91 hp). These fasteners do
not need any additional corrosion-resistant coatings and
tightening behavior can be controlled by the use of simple
lubricants. Corrosion resistance is unchanged over
the entire service life of the joint.

worf928

They were.

I think you've figured-out that you probably can't use a hed head there?

Mattman928

The hall sensor is replaced. It was a tricky project but it can be done without pulling the CAM gear. Thanks to everyone who posted here on the forum with their advice. I learned a couple of things. First, the original bolts strip very easily so just plan to replace them and then use an EasyOut #3 to remove the bolts.

I found the same size bolts at Home depot but the ones I had didn't have a Zinc coating, so I used plenty of Aluminum Anti-seize. Its better to use the correct bolts, but plan on getting new ones.

When replacing them I used a little trick with electrical tape that work perfectly and prevented me from dropping the new bolt.

Mattman928

I disassembled the system again and found nothing abnormal. I took the following picture and sent to 928 Motorsports and Carl seemed this think everything is okay.

Time to button her up again and see how she runs.