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#1
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Hi all,
I was recently gifted an ‘88 924S that hasn’t been driven in a good 8 years. After replacing most of the ignition system (plugs, wires, distributor cap, battery), I got it running, but it spews lots of oil smoke from the exhaust and runs terribly. Compression test results seem pretty good best I can tell (167, 175, 170, 160) and leak down test was all at 9% or better even when tested completely cold. Heard some blow by through the intake in cylinder 3. With this, I’m suspecting my valve seals as the source of the oil in the combustion chamber. Does that stand to reason? If that is indeed the culprit, do you all recommend a valve seal replacement with the head still in the engine bay? Or should I do a full head rebuild just to be safe? Any suggestions how to further determine whether a valve seal replacement is likely to solve my smoke issue? Thanks!
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Jeff -------------------- Garage: 2015 Competizione Rosso Alfa Romeo 4C Coupe (track-prepared) 1993 Vintage Red R-Spec RX7 FD (heavily modded) 2016 Cayenne Turbo 1987 Porsche 924S Cars in Heaven: 1996 Opel Frost Mustang GT (heavily modded) Sold Vehicles: 2012 Cayenne S 2007 Cobalt Blue Cayman S (suspension mods) 2004 Suzuki Blue SV650S (bone stock) |
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#2
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With those compression numbers and leakdown a bit out of range and with air noise past valves, it's time for a head rebuild. Last one I had done was only about $300 for just the head work. I'm sure its more expensive now. I did the disassembly and reassembly myself. If it smokes all the time it may be time for rings as well as valve seals typically only cause smoke at startup. But since this thing sat for so long it may be a case of the seals stuck to the stem and have dislodged allowing oil to get past the guides. Good luck...
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Steve Potomac PCA Co-CI(retired) 89 944 Turbo Race car 85.5 944 NA son's 2015/2019/2020 944Cup and PCA Nat'l Champ racecar 94 968 1 of 11 Iris blue coupes 92 968 1 of 2 Tahoe Blue Cabriolets 98 993 C2S w/Aerokit II 77 911S Vintage race car project 70 Boss 302 86 Mustang SVO 24 F250 SD Godzilla "Noel spun! Noel spun! Don't do anything stupid, Dad." -the boy on the radio on the last lap of NASA race as the second place car spins behind me in T5 at Summit Point. |
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#3
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Quote:
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78 SC, the 'Red Car' |
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#4
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Quote:
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Jeff -------------------- Garage: 2015 Competizione Rosso Alfa Romeo 4C Coupe (track-prepared) 1993 Vintage Red R-Spec RX7 FD (heavily modded) 2016 Cayenne Turbo 1987 Porsche 924S Cars in Heaven: 1996 Opel Frost Mustang GT (heavily modded) Sold Vehicles: 2012 Cayenne S 2007 Cobalt Blue Cayman S (suspension mods) 2004 Suzuki Blue SV650S (bone stock) |
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#5
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I had a VW VR6 head rebuilt by Tysons Machine, seems like fine work and they do stuff for Chapman. Farther out I had a Volvo redblock head done by Billy at Performance Machine in WV. Also fine work, more performance oriented if that's desires.
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Ed Devinney ::: phase 1: collect the underpants. |
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#6
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Thanks! Hadn't heard of either of these companies before - I'll check them out.
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Jeff -------------------- Garage: 2015 Competizione Rosso Alfa Romeo 4C Coupe (track-prepared) 1993 Vintage Red R-Spec RX7 FD (heavily modded) 2016 Cayenne Turbo 1987 Porsche 924S Cars in Heaven: 1996 Opel Frost Mustang GT (heavily modded) Sold Vehicles: 2012 Cayenne S 2007 Cobalt Blue Cayman S (suspension mods) 2004 Suzuki Blue SV650S (bone stock) |
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#7
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I assume Ed meant Billy Ring at Performance Autoworks (8063 Leetown Rd, Middleway, WV 25430 -- (304) 728-8222). Billy is a master, especially with air-cooled--he learned at the knee of Dave Coleman.
Is Allied still in business? They're in Falls Church. I last used them in 1978 so can't vouch for their current work...
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Peter (not "Pete") K. 2026 Lucid Gravity Grand Touring (EV Tow Vehicle) 1997 Spec Boxster #671 2016 Cayman S 2016 Toyota Highlander--wife's DD 2017 VW GTI SE (DD) Gone and missed: 2003 Miata ("SM") race car 1992 Miata ("SSM") race car 2009 911 C2S Coupe 2004 Toyota Prius - sold to son's girlfriend 2006 Dodge Durango 2003 Acura MDX 86 Black 911 Coupe race car 86 Gold 911 Targa 82 WineRedMetallic 911 Targa Last edited by Dr K; 10-31-2024 at 08:01 PM. Reason: Damn spell correction! |
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#8
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Thanks Dr K!
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Jeff -------------------- Garage: 2015 Competizione Rosso Alfa Romeo 4C Coupe (track-prepared) 1993 Vintage Red R-Spec RX7 FD (heavily modded) 2016 Cayenne Turbo 1987 Porsche 924S Cars in Heaven: 1996 Opel Frost Mustang GT (heavily modded) Sold Vehicles: 2012 Cayenne S 2007 Cobalt Blue Cayman S (suspension mods) 2004 Suzuki Blue SV650S (bone stock) |
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#9
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Burtonsville machine shop did my 968, a 944 turbo and 2.2L heads.
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#10
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Billy Ring at Performance Auto Works in Kearneyville WV
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Jim ------ "2014 & 2017 Central PA SCCA Witch's Rallye - Best Team Costume Award" White/Green '91 SSM Miata #01 Silver '00 Miata Green '96 911 (993) Carrera #409 Blue '09 911 (997.2) Carrera S Cab Black '15 Yukon XL w/ '98 Trailex (Tow Vehicle) Burnt Orange '75 FJ40 Yellow '19 718 Boxster (wife regretfully sold it to fit the grandkids) Black '83 911SC Targa (regrettably sold when the second car seat didn't fit and 2nd daughter came along) |
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