SL/R230: blue smoke??
#1
blue smoke??
I recently purchased a 2009 SL550 with 35k miles and been driving it for over a month . I now have 36k and in the last two days when I start it for the first time out comes a noticeable amount of blue smoke. I have had this happen on past cars and not a good sign, but my hope is maybe something different and simple with the SL550, I’m thinking valve stem seals, or a bad piston ring is there anything anyone knows about this year and model and were I can start? I have rebuilt engines and cars, and this is a newer car too me I like old cars.
#2
Senior Member
I recently purchased a 2009 SL550 with 35k miles and been driving it for over a month . I now have 36k and in the last two days when I start it for the first time out comes a noticeable amount of blue smoke. I have had this happen on past cars and not a good sign, but my hope is maybe something different and simple with the SL550, I’m thinking valve stem seals, or a bad piston ring is there anything anyone knows about this year and model and were I can start? I have rebuilt engines and cars, and this is a newer car too me I like old cars.
Last edited by imtheking; 01-20-2023 at 02:58 PM.
#3
MBWorld Fanatic!
if only in AM on first crank something is leaking oil into combustion chambers.
So valve stem seals possibly but they tend to smoke even when warm engine sometimes.
Have to remove valve cover and inspect - check if hard and brittle or any broken.
I do remember back when 450 SL engine we would replace valve stem seals due to getting hard.
Boss would notice when we did a valve lash adjustment.
With proper tools not too hard.
Need plugs out and fitting to pump compressed air in cylinder to hold valves up in head.
Then remove valve springs with proper spring removal tool for engine.
Then pick or something to pull up and out old stem seals and install new.
then back together and proper valve lash.
Could be a PCV issue where too much blow back of crankcase oil vapors back into intake and it collects and then slowly drains down into valve area.
Can confirm by removing all the intake stuff and examining inside looking for motor oil near pcv hose - there can be some but lots is bad.
maybe but I doubt it could be crappy oil ring that needs to get warmed up and expand to seal and wipe cylinder walls properly - doubt this one as you would probably smoke all the time when pistons/rings go bad.
Can confirm with compression check.
This car was not driven much what 13-14 years in service and only 36k = under 3K per year.
I would lean towards stem seals got hard from sitting there without getting much oil over the time she sat off.
If it is only on cold startup and not too bad where you look like you are killing bugs in the area... I would live with it.
check plugs for fouling and excessive oil if they look good just drive.
Maybe try high mileage oil to see if they can help stem seals - maybe one of them oil miracles in a can .
Or bite the bullet and have it inspected
good luck
So valve stem seals possibly but they tend to smoke even when warm engine sometimes.
Have to remove valve cover and inspect - check if hard and brittle or any broken.
I do remember back when 450 SL engine we would replace valve stem seals due to getting hard.
Boss would notice when we did a valve lash adjustment.
With proper tools not too hard.
Need plugs out and fitting to pump compressed air in cylinder to hold valves up in head.
Then remove valve springs with proper spring removal tool for engine.
Then pick or something to pull up and out old stem seals and install new.
then back together and proper valve lash.
Could be a PCV issue where too much blow back of crankcase oil vapors back into intake and it collects and then slowly drains down into valve area.
Can confirm by removing all the intake stuff and examining inside looking for motor oil near pcv hose - there can be some but lots is bad.
maybe but I doubt it could be crappy oil ring that needs to get warmed up and expand to seal and wipe cylinder walls properly - doubt this one as you would probably smoke all the time when pistons/rings go bad.
Can confirm with compression check.
This car was not driven much what 13-14 years in service and only 36k = under 3K per year.
I would lean towards stem seals got hard from sitting there without getting much oil over the time she sat off.
If it is only on cold startup and not too bad where you look like you are killing bugs in the area... I would live with it.
check plugs for fouling and excessive oil if they look good just drive.
Maybe try high mileage oil to see if they can help stem seals - maybe one of them oil miracles in a can .
Or bite the bullet and have it inspected
good luck
#4
if only in AM on first crank something is leaking oil into combustion chambers.
So valve stem seals possibly but they tend to smoke even when warm engine sometimes.
Have to remove valve cover and inspect - check if hard and brittle or any broken.
I do remember back when 450 SL engine we would replace valve stem seals due to getting hard.
Boss would notice when we did a valve lash adjustment.
With proper tools not too hard.
Need plugs out and fitting to pump compressed air in cylinder to hold valves up in head.
Then remove valve springs with proper spring removal tool for engine.
Then pick or something to pull up and out old stem seals and install new.
then back together and proper valve lash.
Could be a PCV issue where too much blow back of crankcase oil vapors back into intake and it collects and then slowly drains down into valve area.
Can confirm by removing all the intake stuff and examining inside looking for motor oil near pcv hose - there can be some but lots is bad.
maybe but I doubt it could be crappy oil ring that needs to get warmed up and expand to seal and wipe cylinder walls properly - doubt this one as you would probably smoke all the time when pistons/rings go bad.
Can confirm with compression check.
This car was not driven much what 13-14 years in service and only 36k = under 3K per year.
I would lean towards stem seals got hard from sitting there without getting much oil over the time she sat off.
If it is only on cold startup and not too bad where you look like you are killing bugs in the area... I would live with it.
check plugs for fouling and excessive oil if they look good just drive.
Maybe try high mileage oil to see if they can help stem seals - maybe one of them oil miracles in a can .
Or bite the bullet and have it inspected
good luck
So valve stem seals possibly but they tend to smoke even when warm engine sometimes.
Have to remove valve cover and inspect - check if hard and brittle or any broken.
I do remember back when 450 SL engine we would replace valve stem seals due to getting hard.
Boss would notice when we did a valve lash adjustment.
With proper tools not too hard.
Need plugs out and fitting to pump compressed air in cylinder to hold valves up in head.
Then remove valve springs with proper spring removal tool for engine.
Then pick or something to pull up and out old stem seals and install new.
then back together and proper valve lash.
Could be a PCV issue where too much blow back of crankcase oil vapors back into intake and it collects and then slowly drains down into valve area.
Can confirm by removing all the intake stuff and examining inside looking for motor oil near pcv hose - there can be some but lots is bad.
maybe but I doubt it could be crappy oil ring that needs to get warmed up and expand to seal and wipe cylinder walls properly - doubt this one as you would probably smoke all the time when pistons/rings go bad.
Can confirm with compression check.
This car was not driven much what 13-14 years in service and only 36k = under 3K per year.
I would lean towards stem seals got hard from sitting there without getting much oil over the time she sat off.
If it is only on cold startup and not too bad where you look like you are killing bugs in the area... I would live with it.
check plugs for fouling and excessive oil if they look good just drive.
Maybe try high mileage oil to see if they can help stem seals - maybe one of them oil miracles in a can .
Or bite the bullet and have it inspected
good luck