Oil in coolant, coolant in oil..
Thread Starter
Newbie
Joined: Aug 2019
Posts: 12
Likes: 2
2004 C230 Sedan
Oil in coolant, coolant in oil..
Suggests head gasket but I’m not so sure. Both the coolant reservoir and the oil cap are white-ish yellow and there’s small little bubbles in the fluid mixture on the oil cap. ATF or just coolant??? Or a mix of all 3??? Transmission started acting wonky a couple days before I noticed the cross contamination. Runs okayish, doesn’t smoke on cold start or overheat, even on the highway and in traffic it didn’t get hot I don’t think. I just bought it SUPER CHEAP with suspicions of a head problem or something, idle was poor, although drove pretty decent. Checked the fluids and they looked dirty but okay. Now this, I’m confused. I’ve seen plenty of head problems in my short time on this earth. None of them quite like this. For a head leak of the size it’d need to cause this much contamination in such a short time if I’m not mistaken it should smoke or overheat at the least. It does neither. I’m not freaking out over a possibly having to pull the head, but I’ve read threads on an oil cooler leak that could possibly cause this. Just wanted to see what some Vets have to contribute on this before it gets torn down. TIA! - Collin
EDIT: Poor idle and performance was mostly caused by a vacuum leak which was fixed within a couple of days. Now it’s only half as bad. Which points me more towards a head gasket as well. Thanks again!
EDIT: Poor idle and performance was mostly caused by a vacuum leak which was fixed within a couple of days. Now it’s only half as bad. Which points me more towards a head gasket as well. Thanks again!
Last edited by Collin Minor; Sep 14, 2019 at 09:55 PM.
Out Of Control!!
Joined: Sep 2018
Posts: 14,663
Likes: 4,567
From: unbegrenzt
2017 GLE350 4MATIC
Get some data. You already have visual data on the reservoir caps, and the wonky transmission performance.
Does the exhaust smell like burning oil, or have a sweet smell?
Do a compression test, and a leak down test.
Do a coolant pressure decay test.
Drain and replace the coolant, engine oil and transmission fluid. Note the color, smell and consistency of each one.
Pull the spark plugs and look at them, note differences in appearance.
Look into the cylinder through the spark plug hole with a bright light, to see if the tops of the pistons are "washed", or shiny from coolant.
Does the exhaust smell like burning oil, or have a sweet smell?
Do a compression test, and a leak down test.
Do a coolant pressure decay test.
Drain and replace the coolant, engine oil and transmission fluid. Note the color, smell and consistency of each one.
Pull the spark plugs and look at them, note differences in appearance.
Look into the cylinder through the spark plug hole with a bright light, to see if the tops of the pistons are "washed", or shiny from coolant.
Thread Starter
Newbie
Joined: Aug 2019
Posts: 12
Likes: 2
2004 C230 Sedan
Get some data. You already have visual data on the reservoir caps, and the wonky transmission performance.
Does the exhaust smell like burning oil, or have a sweet smell?
Do a compression test, and a leak down test.
Do a coolant pressure decay test.
Drain and replace the coolant, engine oil and transmission fluid. Note the color, smell and consistency of each one.
Pull the spark plugs and look at them, note differences in appearance.
Look into the cylinder through the spark plug hole with a bright light, to see if the tops of the pistons are "washed", or shiny from coolant.
Does the exhaust smell like burning oil, or have a sweet smell?
Do a compression test, and a leak down test.
Do a coolant pressure decay test.
Drain and replace the coolant, engine oil and transmission fluid. Note the color, smell and consistency of each one.
Pull the spark plugs and look at them, note differences in appearance.
Look into the cylinder through the spark plug hole with a bright light, to see if the tops of the pistons are "washed", or shiny from coolant.
Thread Starter
Newbie
Joined: Aug 2019
Posts: 12
Likes: 2
2004 C230 Sedan
It doesn’t have a sweet smell from exhaust nor does it smell like oil. All I smell is a strong odor of gasoline but past that nothing else. I wish I had all the tools available to me to do such. At the moment I do not. I’m pretty sure you need an E-socket to get the coils out anyways and I do not have a set. Will be picking one up Friday. But for now, any guesses? It’s a C230K. Around 190,000 miles. Bought it to see if I could make something cool out of it. Don’t see many of these on tracks and at meets and such. Figured I’d try my hand.
Super Member
Joined: Sep 2016
Posts: 571
Likes: 92
From: New England! :-)
2005 C230K Sport Coupe
If you're in the USA, at least put what general part of the Country that you are in.
Fwiw, the M271 American-version is unique.
Check the oil-cooler for a leak. Search.
Do a dry and wet compression test.
As for the oil/coolant in the spark plug holes, likely some incompetent person yanked the valve cover, and put it back on wrong, or re-used a bad gasket.
Your timing chain is a massive POS! It should be REPLACED every ~70K miles. The M271 is an interference engine.
You don't have to change the timing chain. You also don't have to ever ever change the oil.
What type of "track" - NASCAR, Circle, Auto-x, 1/4 mile?
For a GOOD AMOUNT OF MONEY (~$5K+++), there's ~~~20-30 real life HP that can be gained.
Is that "worth it"? Imho, that's a depends on the person and the reasons.
Imho, everything (HP wise) else is BS snake oil - buy an ebay battery-powered supercharger, put on a 12-foot wing on the back, put neon lights under the car, and you're well on your way.
There are some stiffer sway bars. Wider tires likely won't fit. Get/use REAL (DOT-legal) race tires for the track.
Good Luck!
Fwiw, the M271 American-version is unique.
Check the oil-cooler for a leak. Search.
Do a dry and wet compression test.
As for the oil/coolant in the spark plug holes, likely some incompetent person yanked the valve cover, and put it back on wrong, or re-used a bad gasket.
Your timing chain is a massive POS! It should be REPLACED every ~70K miles. The M271 is an interference engine.
You don't have to change the timing chain. You also don't have to ever ever change the oil.
What type of "track" - NASCAR, Circle, Auto-x, 1/4 mile?
For a GOOD AMOUNT OF MONEY (~$5K+++), there's ~~~20-30 real life HP that can be gained.
Is that "worth it"? Imho, that's a depends on the person and the reasons.
Imho, everything (HP wise) else is BS snake oil - buy an ebay battery-powered supercharger, put on a 12-foot wing on the back, put neon lights under the car, and you're well on your way.
There are some stiffer sway bars. Wider tires likely won't fit. Get/use REAL (DOT-legal) race tires for the track.
Good Luck!
Last edited by RedGray; Sep 16, 2019 at 01:53 AM.
Super Member
Joined: Sep 2016
Posts: 571
Likes: 92
From: New England! :-)
2005 C230K Sport Coupe
Btw, as for NASCAR-type of tracks, a person here posted his C230K on a real track (?Talladega?). His normal track car was down for the week. He also has extensive track time and knowledge.
Imho, a C230K, properly done, can be a "respectable" track car. The Vettes, Stangs, and BMWs are still going to blow by. I said respectable, not top competitor worthy.
Oh yea, you should also upgrade the brakes. Again, search.
Good luck.
Imho, a C230K, properly done, can be a "respectable" track car. The Vettes, Stangs, and BMWs are still going to blow by. I said respectable, not top competitor worthy.
Oh yea, you should also upgrade the brakes. Again, search.
Good luck.
Out Of Control!!
Joined: Sep 2018
Posts: 14,663
Likes: 4,567
From: unbegrenzt
2017 GLE350 4MATIC
Good job on collecting more information. You bought the car cheap, you are now getting an idea why it was so cheap. If it were mine, would go through the engine thoroughly, using the diagnostic tests listed above. Depending on your goals for the vehicle, there are options. Repair or replace the engine are the two basic avenues to consider.
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Super Member
Joined: Sep 2016
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From: New England! :-)
2005 C230K Sport Coupe
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Thread Starter
Newbie
Joined: Aug 2019
Posts: 12
Likes: 2
2004 C230 Sedan
Good job on collecting more information. You bought the car cheap, you are now getting an idea why it was so cheap. If it were mine, would go through the engine thoroughly, using the diagnostic tests listed above. Depending on your goals for the vehicle, there are options. Repair or replace the engine are the two basic avenues to consider.
Last edited by Collin Minor; Sep 17, 2019 at 11:27 PM.
Thread Starter
Newbie
Joined: Aug 2019
Posts: 12
Likes: 2
2004 C230 Sedan
If you're in the USA, at least put what general part of the Country that you are in.
Fwiw, the M271 American-version is unique.
Check the oil-cooler for a leak. Search.
Do a dry and wet compression test.
As for the oil/coolant in the spark plug holes, likely some incompetent person yanked the valve cover, and put it back on wrong, or re-used a bad gasket.
Your timing chain is a massive POS! It should be REPLACED every ~70K miles. The M271 is an interference engine.
You don't have to change the timing chain. You also don't have to ever ever change the oil.
What type of "track" - NASCAR, Circle, Auto-x, 1/4 mile?
For a GOOD AMOUNT OF MONEY (~$5K+++), there's ~~~20-30 real life HP that can be gained.
Is that "worth it"? Imho, that's a depends on the person and the reasons.
Imho, everything (HP wise) else is BS snake oil - buy an ebay battery-powered supercharger, put on a 12-foot wing on the back, put neon lights under the car, and you're well on your way.
There are some stiffer sway bars. Wider tires likely won't fit. Get/use REAL (DOT-legal) race tires for the track.
Good Luck!
Fwiw, the M271 American-version is unique.
Check the oil-cooler for a leak. Search.
Do a dry and wet compression test.
As for the oil/coolant in the spark plug holes, likely some incompetent person yanked the valve cover, and put it back on wrong, or re-used a bad gasket.
Your timing chain is a massive POS! It should be REPLACED every ~70K miles. The M271 is an interference engine.
You don't have to change the timing chain. You also don't have to ever ever change the oil.
What type of "track" - NASCAR, Circle, Auto-x, 1/4 mile?
For a GOOD AMOUNT OF MONEY (~$5K+++), there's ~~~20-30 real life HP that can be gained.
Is that "worth it"? Imho, that's a depends on the person and the reasons.
Imho, everything (HP wise) else is BS snake oil - buy an ebay battery-powered supercharger, put on a 12-foot wing on the back, put neon lights under the car, and you're well on your way.
There are some stiffer sway bars. Wider tires likely won't fit. Get/use REAL (DOT-legal) race tires for the track.
Good Luck!
Super Member
Joined: Sep 2016
Posts: 571
Likes: 92
From: New England! :-)
2005 C230K Sport Coupe
For a MB, search by the engine name (M271) and/or the chassis name (W203).
Google:
M271 oil cooler replacement.
As for why it leaks, it's a cheap/poor design.
Here's an article about replacing the gasket on another engine. Note that it's a PITA on an M271.
https://www.pelicanparts.com/techart...eplacement.htm
The following picture should give you an idea why the oil and coolant may mix:
Note that, all coolant is very corrosive to all bearings and bearing surfaces. The longer that there is coolant in the oil, the more damage that is done to the bearings and the bearing surfaces.
Knowing the needed maintenance areas, and being able to do the work oneself, can make an older MB a good purchase.
Otherwise, imho, the purchase is a waste of money.
Good Luck.
Google:
M271 oil cooler replacement.
As for why it leaks, it's a cheap/poor design.
Here's an article about replacing the gasket on another engine. Note that it's a PITA on an M271.
https://www.pelicanparts.com/techart...eplacement.htm
The following picture should give you an idea why the oil and coolant may mix:
Note that, all coolant is very corrosive to all bearings and bearing surfaces. The longer that there is coolant in the oil, the more damage that is done to the bearings and the bearing surfaces.
Knowing the needed maintenance areas, and being able to do the work oneself, can make an older MB a good purchase.
Otherwise, imho, the purchase is a waste of money.
Good Luck.
MBWorld Fanatic!
Joined: Jun 2002
Posts: 7,263
Likes: 169
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Ah OK, so sounds like 2 issues,
1. this oil cooler (assuming you have M271)
2. Valve cover gasket and orings around the spark plug holes (go on the vavle cover)
thats how oil (and since coolant is getting in the oil)
gets into the area where the coil is.
1. this oil cooler (assuming you have M271)
2. Valve cover gasket and orings around the spark plug holes (go on the vavle cover)
thats how oil (and since coolant is getting in the oil)
gets into the area where the coil is.
Junior Member
Joined: Aug 2007
Posts: 60
Likes: 9
94 e320s
i had a friends 271 4 cylinder with oil in coolant , looked like milk shake , was the oil cooler small box looking one, and tested it by closing the oil port and installing in a bucket of water and putting air into the oil section , bubbles leaked
