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Join Date: Nov 2003
Posts: 692
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Premature valve guide wear
Hi All -
What would cause valve-guide wear in a 3.2 w/ 16K miles? When doing a rebuild, what can be done to avoid it? How long should the guides last if done correctly? Thanks. |
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11-15-2003, 09:04 AM
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Join Date: Oct 2001
Location: San Carlos, CA US
Posts: 5,521
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That is pretty premature, even for an engine known for eating valve guides prematurely. Lack of adequate lubrication perhaps? Did you use the right material valve guides in the first place?
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Porsche 2005 GT3, 2006 997S with bore-scoring Exotic: Ferrari F360F1 TDF, Ferrari 328 GTS Disposable Car: BMW 530xiT, 2008 Mini Cooper S Two-wheel art: Ducati 907IE, Ducati 851 |
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11-15-2003, 09:10 AM
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Join Date: Oct 2003
Location: Sacramento, CA
Posts: 666
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What valve seals did you use when you assembled the engine? If they are "too good" they will starve the guide of lubrication
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Paul S "Those who say it cannot be done should not interrupt the people doing it" |
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11-15-2003, 09:18 AM
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Not my car, but...
The factory guides were used. They weren't supposed to be, but they were... Custom bronze-phosphate ones go in next time. I believe the seals were Vinton. So, what should be the longevity if done right |
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11-15-2003, 09:28 AM
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Not unheard of...check this story:
http://www.kindel.com/Porsche/Valves.htm There have been SC engines with over 200K miles (and higher) with no major engine work. The valve guides *should* last hundreds of thousands of miles. Some of the 3.2 cars had issues, and I believe that the newer 3.6 engines also tend to wear valve guides quicker. |
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11-15-2003, 09:39 AM
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Information Junky
Join Date: Mar 2001
Location: an island, upper left coast, USA
Posts: 73,189
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MUHAHAhahaha . . .. .eh.
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Everyone you meet knows something you don't. - - - and a whole bunch of crap that is wrong. Disclaimer: the above was 2¢ worth. More information is available as my professional opinion, which is provided for an exorbitant fee. 
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11-15-2003, 09:44 AM
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Not Quite Banned
Join Date: Dec 1999
Location: Ft. Lauderdale
Posts: 1,222
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16k and the guides are worn? Are you sure about the mileage? My research showed that the original seals did 'too good of a job' in that the guide/valve stem area was not sufficiently lubricated. The new seals solve that problem, and I believe they are white in color. You may want to verify this with John Walker.
Good luck,
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Thomas Owen 1972 911T 1972 911S |
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11-15-2003, 09:48 AM
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Are the old crappy seals still availible? Or has this problem been fixed?
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1987 535is, 1966 GTV, 2015 F-Type R, 2013 991 C2, 2011 E550c, 2007 997 C2S, 1987 911, 1958 356 1600s, 1956 356 1600s |
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11-15-2003, 10:30 AM
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Join Date: Jun 2003
Location: Camarillo, Ca.
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Rumors of inferior valve guide material, and a too lean condition are also suspects in 3.2s but for some reason not all. go figure
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Aaron.  F.S. 1965 Solex engine w carbs/cleanerBurnham Performance https://www.instagram.com/burnhamperformance/ |
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11-15-2003, 10:57 AM
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Driving member
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I just rolled over 75k so I hope I am past the valve guide issue, at least for another 75. My oil consumption is not bad and I don't have a smoking issue.
16k though is awfully low. Hardly seems broken in at that point.
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Jerry '86 coupe gone but not forgotten Unlike women, a race car is an inanimate object. Therefore it must, eventually, respond to reason. |
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11-15-2003, 11:09 AM
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1979 Porsche 911SC 3.0
1986 Porsche carrera coupe 3.2
