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Join Date: Feb 2006
Location: Ontario Canada
Posts: 2,947
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3.2 Valve guide work
I have a friend who rebuilds a fair number of 911 engines , he usually does pre 3.0 litre stuff and has a fair bit of experience at it ... a mutual friend of ours talked him into doing his 3.2 which has excessive smoking.
He found leaking of oil actually between the valve guides and the head, so is sending them off to machine shop for repair ( also oil scraper rings are totally clogged on the ones where he spotted evidence of oil seepage at the guides. ). I hear a lot of issues with 3.2 valve guides, is this the normal failure mode on the exhaust guides ?? Also he told me it has lower black Dilivar head studs. I did my engine because of broken studs (3.0) but i was wondering with all the valve guide work done on 3.2s for valve guide work is it standard practice to replace these ? refresh with Dilivar , or just leave them alone if they are fine ? Thanks Guys
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1976 Yamaha XS360 ( Beats Walkin') 1978 911 SC Targa ( Yamaha Support Vehicle ) 2006 Audi A4 2.0T (Porsche Support Vehicle ) 2014 Audi A4 2.0T Technik (Audi Support Vehicle) |
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06-22-2021, 05:57 AM
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Easily Confused
Join Date: Feb 2005
Location: Republic of Texas
Posts: 429
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I'm in the process of doing this now due to valve guide issues at 85k miles. My dilivars were in good shape but I replaced them with steel studs as a precaution.
As far as failure mode, I think most develop wear between the guide and valve. Also, not to add to his repair tab, he may want to consider Titanium retainers.
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Scott C. '08 Cayenne GTS 6MT : '89 Targa GP White/Black - "Oliver's Car" : '11 Mitsu Evo X : '08 Lexus IS350 F-Sport : '01 Toyota Sequoia : 1998 Yamaha V-max : 1979 BMW R65 |
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06-22-2021, 06:07 AM
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Join Date: Oct 2008
Location: Nash County, NC.
Posts: 8,480
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Black or silver, dilivar will break with the retorque.
In 1989 or 90 I torques a set of heads then went to bed. Next morning, broken studs everywhere Replace them with steel and cut the down time… Bruce |
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06-22-2021, 08:29 AM
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Join Date: Mar 2019
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That failure isn't common. The guide to head is an interference fit, so if something leaks, it's because the guide hole in the head wasn't round or was galled or damaged. The guides wear out at the valve stem.
Replace the head studs while you have it apart. |
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06-22-2021, 08:51 AM
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Join Date: Feb 2006
Location: Ontario Canada
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great info , thanks guys ...
i have passed the advice on. i thought so too about the dilivar , but wasnt sure about the valve guide stuff.. either way guides are getting replaced so machine shop should resolve any issues i would imagine.
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1976 Yamaha XS360 ( Beats Walkin') 1978 911 SC Targa ( Yamaha Support Vehicle ) 2006 Audi A4 2.0T (Porsche Support Vehicle ) 2014 Audi A4 2.0T Technik (Audi Support Vehicle) Last edited by theiceman; 06-22-2021 at 10:31 AM.. |
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06-22-2021, 10:26 AM
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Passed along the advice and he is adding new studs to the order.. didnt bother with the retainers though.
Not my build so ..
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1976 Yamaha XS360 ( Beats Walkin') 1978 911 SC Targa ( Yamaha Support Vehicle ) 2006 Audi A4 2.0T (Porsche Support Vehicle ) 2014 Audi A4 2.0T Technik (Audi Support Vehicle) |
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06-22-2021, 01:05 PM
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The 9 Store
Join Date: Dec 2009
Location: Wilmington, DE
Posts: 5,340
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Quote:
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All used parts sold as is. |
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06-22-2021, 07:29 PM
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Join Date: Jul 2001
Location: mt. vernon Wa. USA
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Dilivar bad...steel good.
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[B]Current projects: 69-911.5, Previous:73 911X (off to SanFrancisco/racing in Germany).77 911S (NY), 71E (France/Corsica), 66-912 ( France), 1970 914X (Wisconsin) 76 911S roller..off to Florida/Germany RGruppe #669 http://www.x-faktory.com/ |
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06-25-2021, 08:21 AM
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