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Discussion Starter #1
Hi All - this is mostly directed at UrdnotWrexSTi because I followed his write-up, but feel free to chime in with thoughts.

In the process of cleaning out the AVCS gears, I discovered some nice brass colored specs in the plastic brackets that hold the metal springs within both of the intake gears (I haven't started tackling the exhaust yet). Despite my best efforts scrubbing with a toothbrush, it won't come out; the metal is embedded.

My concern here is I'm not sure if any amount of foreign metal is allowable, since it may be stuck in the plastic, never to dislodge. Should I get new gears, should I try some fine grit sandpaper, or what?

I'll post a link to a pic shortly...
 

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Pic link not working. Without it, it's hard for me to understand that embedded brass is not supposed to be there, IE how does brass get there, and then get permanently "attached" on its own . . .
 

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Discussion Starter #5
I updated the link, sorry about that. Financially, I'd greatly prefer to fix the little plastic clips than spend $750 on a new set of four.
 

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Discussion Starter #7
pics working now

thats quite a bit of brass in the plastic.

can you try to dig it out with a dentist pick and tweezers?
Hm..Maybe, but the picture is blown up to about 50x actual size; the metal bits are smaller than glitter or sand. I'll try the dentist pick idea when I get home, thanks for the idea!
 

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Discussion Starter #8
Update - I took the two intake ones apart again, and was able to use a knife at a 90 degree angle to gently scrape a small layer off. It took the metal with it, and they're looking good as new. Unfortunately, I started on the exhaust side tonight. First off, that spring is ON THERE. Second...I'm afraid I snapped the pin that's in there when removing the bolts, and they're going to have to be replaced. I cannot get the plastic shims out of the exhaust side, and I'm sure they have the same metal problem, so even if the pin wasn't broken I'd still have to replace those two. I'll take a picture of why I think it's broken later tonight.
 

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I personally think you should just bite the bullet and replace the gears. Its not worth the hassle of cleaning. Also peace of mind is priceless in my opinion.
 

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Discussion Starter #11
Why are you cleaning them in the first place? Did you spin a bearing or just wanted to be thorough in your build?
Yup, car was...guzzling oil I guess, and long story short, spun bearing, rod knock. I did manage to get the shims out of the exhaust avcs gears, and I cleaned it all as best as I could. The small pin that aligns the lobed part to the housing I've heard can get sheared off if you use the belt method to remove, or if you use a company 23 tool, and mine both look a little bit bent...but intact. That's what I was going to take a picture of. Since I was able to get the springs and clips out and clean everything, I decided I'll just reuse all four gears. If I'm mistaken in this next bit, please correct me, but I don't think an avcs seizing up or being misaligned will cause a catastrophic failure, so I can hold off on replacing those.

One more note....those exhaust springs are really tough to get back on. I used a set of vice grips about 2/3 the way back around the spring to twist it back into place and used my other hand to fight the bent part of the spring into the center hole. The method worked extremely well on the second one....learning curve, I guess.
 

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I was able to get the springs and clips out and clean everything, I decided I'll just reuse all four gears. If I'm mistaken in this next bit, please correct me, but I don't think an avcs seizing up or being misaligned will cause a catastrophic failure, so I can hold off on replacing those
Although functionality is important, isn't the risk is that a piece of metal gets to a bearing and provides you with the pleasure of redoing the whole experience.

You know how well you cleaned em . . . sounded thorough here :) I'd still like to know where the brass came from and why it was so embedded. The solenoids are brass?
 

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Honestly, these gears are very important to the timing of our engines, so anything seizing inside these gears could eventually lead to failure somewhere. I didn't post on the forum, but I actually underwent a second rebuild due to a burnt valve. Which I attributed to my AVCS exhaust gear being damaged. This made the AFRs lean out under boost and I think is what burnt that valve. Anyway, this time I dropped in an IAG closed deck block and got the heads on a mild build. Now it's making 505hp :D


Okay, so as far buying new gears, if you're worried something is damaged inside, then learn from me and just replace the whole gear. Like I said they do a lot for the timing of the engine.



Looking at that retainer you took a picture of, it actually doesn't look like brass to me, technically there shouldn't be any. To me it looks like it's copper or some other metal that's in bedded itself in the plastic, and since metal should NOT be anywhere near those gears, I'd say you've probably been burning up a bearing for a little while and it contaminated your whole oiling system. Check your heads for the same metal particles as well, and make sure to check the camshaft journals and the surface where the camshafts ride on. Turbo could also be compromised.
 

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Looking at that retainer you took a picture of, it actually doesn't look like brass to me, technically there shouldn't be any. To me it looks like it's copper or some other metal that's in bedded itself in the plastic, and since metal should NOT be anywhere near those gears, I'd say you've probably been burning up a bearing for a little while and it contaminated your whole oiling system. Check your heads for the same metal particles as well, and make sure to check the camshaft journals and the surface where the camshafts ride on. Turbo could also be compromised.
I could not tell from the pic, but copper makes far more sense than brass - far more since you spun a bearing. Seeing this though it Makes me feel feel much better about IAGs insistence on replacing my cam gears. In fact it was about thew only thing they insisted on, and at the time I thought it might have been over-kill. My car did not spin a bearing, but copper was visible on the bearings themselves. Paying them to clean em would not have been cost effective. They did not push anything else on me.
 
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