Author Topic: 230sl fully re built engine and injection pump causing plugs to be coated in oil  (Read 1779 times)

Raffles84

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Hi, my 230sl engine has been fully rebuilt and also the injection system - now it’s covering the plugs in oil and burning oil when turned on! Any ideas what to check??

Tyler S

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How many miles/km is on the engine?
Remove the oil cap while the engine is idling and check for blow-by.
Also be sure you are NOT using synthetic or synthetic blend oil during break in.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

Raffles84

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The engine has been fully re built and all new pistons etc! Using Castrol Classic oil specially for this pagoda. Thanks

Tyler S

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Check for blow-by as it may help point you in the right direction being valve guides/seals or oil control rings. How many miles on the rebuild?
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

ja17

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If it is an automatic, make sure you are not sucking up transmission fluid into the engine. Are all the spark plugs, getting oil on them?
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Raffles84

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Hi it’s had no miles on the rebuild was trying to get it running a bit before I send it for tuning. Just started and ideled a bit

Cees Klumper

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Could it be the assembly lube burning off?
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

Tyler S

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With zero miles it needs to be broken in. If you can get it started hold the rpm at around 2000 for 10 minutes. Then put some miles on it with differing speeds.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

ja17

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Yes could be sucking in assembly lubes. Did they bore the block along with new oversize pistons?
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Raffles84

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Yes the block was bored and new pistons etc. A complete re build was done.

ja17

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You might have to install a fresh set of plugs and run it a bit more to clear up the problem or determine the issue.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback