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Rusty cam gear sprockets

 
Old 03-18-2012, 05:20 PM
  #1  
Leon Speed
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Default Rusty cam gear sprockets

Are these excessively rusted or is this normal? Reusable or garbage?







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Old 03-18-2012, 06:53 PM
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How well do they fit on the ends of the camshaft? If the are very snug and have to go on straight to fit then i would say they are fine. If there is any noticeable wobble or tilt to the fit as they slide along the cam end I would say change them.

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Old 03-18-2012, 06:55 PM
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Herman K
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UnusuaL to see that kind of pitting but if they still fit snug coat the inside with a Molykote G-n Metal Assembly Paste (Dow Corning) and use them again
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Old 03-18-2012, 07:17 PM
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Originally Posted by Herman K View Post
UnusuaL to see that kind of pitting but if they still fit snug coat the inside with a Molykote G-n Metal Assembly Paste (Dow Corning) and use them again
Maybe there was a leaky water pump sometime in the cars history giving a steamy environment inside the covers, with condensation on cool down?

I would be concerned with the possible lubricating effects of the assembly paste both on the inside and, more critically, on the stepped end of the cam face. The consequences of a lubricating effect might mean premature loosening of that cam sprocket hub, and then hammering of the keyway and everything else that goes with the slight rotational movement. I think I'd just be using them clean and dry if they're still dimensionally OK.
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Old 03-18-2012, 07:25 PM
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They fit very snug. In fact, I had to use a puller to get them off. I guess these haven't been off since new.
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Old 03-18-2012, 07:27 PM
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Not really worth taking the chance. They are only about 30 bucks each. Mine looked alot worse when I had to replace them.
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Old 03-19-2012, 12:00 AM
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I would replace these parts and install them dry,
any lubricant will reduce the clamping effect given by the cam bolt,
and thus cause possibly catastrophic damage.

It is common for these parts to crack along one of their shanks, with the corrosion on the inside of the spider bore it may have a place to happen.

These are critical to cam timing
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Old 03-19-2012, 11:02 AM
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Agree with the above, get new ones and install dry.
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Old 03-19-2012, 05:11 PM
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Hey, not a bad price for a Porsche part. For the price of new it makes sense to replace it. I do have some discoloration on the cam noses as well, but noting to be done about that unfortunately.
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Old 03-19-2012, 08:02 PM
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for the cams dress the surface with some 600 grit and oil ,
clean with acetone when your ready to fit the new parts,
be careful with the front seals so they dont get acetone on them
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Old 03-19-2012, 08:18 PM
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I would NEVER consider using them. When they fail it's big $$$$$$$$
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Old 03-19-2012, 08:20 PM
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REPLACE THEM. Mine were rusty that broke when the end of the cam shaft broke off on the drivers side and am currently replacing all the valves on that side.
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Old 03-20-2012, 05:55 PM
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I'm convinced! I'll replace them.


Originally Posted by Mrmerlin View Post
for the cams dress the surface with some 600 grit and oil ,
clean with acetone when your ready to fit the new parts,
be careful with the front seals so they dont get acetone on them
Mrmerlin any special reason for acetone? Will denatured alcohol work? I have that at hand. Front seals will be replaced.
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Old 03-20-2012, 08:10 PM
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acetone will evaporate the quickest and leave the surface grease free,
alcohol may not cut the oil from the metal as well
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Old 03-21-2012, 03:54 AM
  #15  
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They look normal to me

Glass bead blast them and spray on some black paint.
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