VANOS rebuild

[diver60]

Hey guys, I just wanted to say that I find this site invaluable for diagnosing problems and getting the confidence to do work on my car that I would not normally attempt. In particular, I saw an article on the double vanos system and, at the time I was ready to replace the valve cover gasket, decided to replace the rings on the vanos pistons as well. The post had a link to Besian which detailed the rebuild including parts. I experienced immediate results as a hesitation in low gear was no longer evident. Also, the service manual that I was referencing advised to obtain TDC and lock the cams in place as well as the flywheel. The forum stated that this was not necessary which saved me time and money. I must add that the most controversial thread that I read concerned the replacement of the spark plugs with pros and cons on using anti seize and the efficiency of the various spark plug configurations. In the end, I ended up cleaning the anti seize off the plugs, which I had always used, and installed them clean. But the point is that there was a lot of information on the subject in which to make an educated decision. Thanks to all who contributed. My next job will be to install fog lights on my 2.3. Any comments on OE vs. replacement parts

[chuter]

Just what was your reasoning for removing the anti-seize from the spark plugs? I too have used it for years and years and not using it does not make a lot of sense.

[Randy Forbes]

Just what was your reasoning for removing the anti-seize from the spark plugs? I too have used it for years and years and not using it does not make a lot of sense.

Same here, after reading about a 356 owner that stripped a plug thread in their (expensive) aluminum head!

Well that was in the 60s and I'd used it ever since. Today's plugs__when new__have an anti-gall plating on them, so it really isn't required.

I've also found that once you put it on, you likely never have to reapply, as there's always some trace of it left behind (and you don't know anybody that puts it on more sparingly that I do).

Some things about plugs and aluminum heads; unless it's absolutely necessary (like for a leak-down test or compression check) don't remove the plugs from a HOT engine. Wait until everything cools down, as aluminum and steel have different rates of expansion.

If you're pulling cold plugs from a cold engine and they feel like they're sticking, or dragging, stop and spray a little bit of oil down there. Doesn't take a lot, but a shot from an aerosol Multi-Purpose or penetrating type oil and let it soak a few, then turn the plug back and forth a few times and it will come out easily. Ideally, you would've used compressed air and blown out the plug recesses BEFORE you started, but and oil that ran into the cylinder will burn up the first time it's started back up.

So the moral of this story is that if you're using new plugs that still have a silver plating on them, you don't need to apply the anti-seize lube. If it helps you sleep better at night, then a little smear of it won't hurt__at least it hasn't on any of mine, going back since the year 2000.

These plugs are an example of ones that required a shot of oil to come out smoothly. Had I been reusing them, they definitely would've gotten a smear of Kopr-Shield (that's the only type I use).





BTW, I had rebuilt the VANOS on this one too (along with rod bearings, and that doesn't begin to cover the work on the rest of the car)

[diver60]

Just what was your reasoning for removing the anti-seize from the. spark plugs? I too have used it for years and years and not using it does not make a lot of sense.

I too have always use the anti-seize in the past (on my Volkswagen bugs and BMW 2000) and had no problems. I guess since this was my first plug change in the Z3, I did not want to over torque the plugs and I knew that I would still have some residual on the threads. I also read some articles about the anti-seize potentially changing the plugs conductivity and possibly affecting the spark if it ended up on the electrode. Anyway, as was mentioned, the newer plugs are coated to resist seizing. I guess, in the end, I erred on the side of caution.