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Adding Oil to Coolant?

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Flavoade

10+ Year Contributor
64
18
Apr 1, 2012
Baton Rouge, Louisiana
Just as the title says.

Entertain this before shooting it down:
My coolant boiled over. I thought the fan thermo switch died. I drain my coolant and it comes out brown and strong smelling. I check the switch, but it still works. I flush a dozen gallons of water through the cooling system and most of the water was a dark brown color.

I thought it was my headgasket, but I just had my oil changed to some red stuff and I did not find any mayonnaise. I put some fresh coolant in, start it up, and it runs great.

My question is this:
Is it possible that some bros at the shop had too many beers and put oil into the radiator thinking it was coolant? Is there a secret trick to keeping the cooling system from corroding? Is this sabotage?

I have the old coolant in a jug and it appears to contain: Anti-Freeze, Water, Fresh Motor Oil, Gasoline, and some kind of additive.

It stained my driveway when it boiled over.
 
First, do a compression test to confirm your head gasket is still good. Anything is possible, but real numbers from a test you do will be the only true indicator.

To keep scale form building up in the coolant system, you need to use DI (deionized) water or some sort of filtered water - if you make up the 50/50 mix yourself. Tap water typically is very hard (meaning it has calcium), and a variety of other minerals and chemicals. When the coolant mixture heats up, the minerals precipitate out of the mixture and form a build up in the system.

Once again, do a compression test.
 
First, do a compression test to confirm your head gasket is still good. Anything is possible, but real numbers from a test you do will be the only true indicator.

To keep scale form building up in the coolant system, you need to use DI (deionized) water or some sort of filtered water - if you make up the 50/50 mix yourself. Tap water typically is very hard (meaning it has calcium), and a variety of other minerals and chemicals. When the coolant mixture heats up, the minerals precipitate out of the mixture and form a build up in the system.

Once again, do a compression test.

You could also pressurize the cylinder via an air compressor attachment, and see if you get bubbles, but you'd have to take off your thermostat to see. That's also assuming you're able to blow past the gasket at those pressures. It may only lift under boost.
 
I wouldn't be surprised if they did put oil in the coolant by accident. I have seen some strange things when I worked at the dealer. You have to make sure your head gasket is good and your compression is good. If they all check out there is not my places oil and coolant can mix, other than maybe a coolant/oil cooled turbo. I would keep an eye on it.
 
Or the oil cooler plate has been over torqued and pushed oil into the coolant system.


But, with the age of the engine, and if it is still on the factory build, the mud is from rust and scale build up in the block.
 
Or the oil cooler plate has been over torqued and pushed oil into the coolant system.


But, with the age of the engine, and if it is still on the factory build, the mud is from rust and scale build up in the block.
 
I had the latter from so much crud in my system and radiator and did experience overheating from all of this blockage.

I took my radiator out and pressure flushed it out and had so much sediment in the bottom of the radiator.

I then pressure flushed out the block by taking off the "T-stat" and forced the water in from both ends - the inlet and the lower hose - where so much rust was pushed out.

I made sure I had clean water coming from both ends before reassembly.

After a new "t-stat", cap and gasket, my coolant has been "clean and green" and under control since..and this was 4 yrs ago.

This last year, I did a heater core changeout due to the crud that was still in the core that had hardened up from the prior.

-DSM
 
Sorry guys, I should have mentioned this is kind a of continuation from my last thread: Buck and Stall After boost - http://www.dsmtuners.com/forums/newbie-forum/474837-buck-stall-after-boost.html#post153384755.

I will do a compression test to see if everything is still green.

I never knew the turbo DSMs were so sensitive:hmm:. I know its old, but it seems like 2 fixes make 5 problems.

To BogusSVO: I am on a fresh rebuild with about 400 miles on it. Had it built by a guy who worked for the Mitsubishi dealer when the DSMs first came out.

I put some fresh coolant in and got it running, to find out the return off the fuel rail was leaking. After fixing this and another snorkel issue. I took it for a test drive, with fans working correctly, and driving coolant temps around 170(Cold night). When i get back home I pop the hood to inspect and see coolant pouring out through the cap; found out my cap is bad as well.

I love my car:D
 
Sorry guys, I should have mentioned this is kind a of continuation from my last thread: Buck and Stall After boost - http://www.dsmtuners.com/forums/newbie-forum/474837-buck-stall-after-boost.html#post153384755.

I will do a compression test to see if everything is still green.

I never knew the turbo DSMs were so sensitive:hmm:. I know its old, but it seems like 2 fixes make 5 problems.

To BogusSVO: I am on a fresh rebuild with about 400 miles on it. Had it built by a guy who worked for the Mitsubishi dealer when the DSMs first came out.

I put some fresh coolant in and got it running, to find out the return off the fuel rail was leaking. After fixing this and another snorkel issue. I took it for a test drive, with fans working correctly, and driving coolant temps around 170(Cold night). When i get back home I pop the hood to inspect and see coolant pouring out through the cap; found out my cap is bad as well.

I love my car:D

who sold you the car, the devil?? ;) your getting a bunch of weird problems. :hmm:
 
Just because the guy who built the engine worked at the dealer back in the day doesn't mean he cleaned the block water jacket well.

I fight with blocks daily to get the crud out, even with the equipment I have.

If you still have the factory freeze plugs, good chance you still have mud in the block.
 
who sold you the car, the devil?? ;) your getting a bunch of weird problems. :hmm:

He was a businessman with an accent :)

Just because the guy who built the engine worked at the dealer back in the day doesn't mean he cleaned the block water jacket well.

I fight with blocks daily to get the crud out, even with the equipment I have.

If you still have the factory freeze plugs, good chance you still have mud in the block.

Maybe he was drunk?? Beer in left hand, wrench in the other?

I did a Compression test while cold if that makes difference. The lowest reading was 129 and the highest 145. It was 129 + 140 +140 + 145 / 4 = 138.5.

I re-torqued the head bolts and one was pretty loose, and 2 were kinda loose. After doing the head bolts I did another compression check and readings were the same.

After all this I went for a test drive and when I got back into the driveway I checked the engine and saw coolant gushing out through the radiator cap. I replaced the cap then I found out the return off the fuel rail was leaking. I fixed that then the lower hose off the back of the thermostat was leaking coolant, and took care of that.

So far no more overheating or coolant issues. I asked my mechanic about it and he said maybe it was gunk leftover in the heating core. My car sat at his shop with no motor in it for more than a year so maybe.

I am almost certain I smelled petroleum solvents when I drained it though.
 
The only time my oil and coolant have mixed was right before my block blew up. I would be careful.
 
Just because the guy who built the engine worked at the dealer back in the day doesn't mean he cleaned the block water jacket well.

I fight with blocks daily to get the crud out, even with the equipment I have.

If you still have the factory freeze plugs, good chance you still have mud in the block.

I kind of trust my Wrench's work. If there is a problem or crack in the water jacket it was most likely done by the machine shop. Its a shame; a person can piece together their engine to perfection, but have to send the block to a machine shop and they ruin it.

Just to point out, compression is low across the board.

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

1G (90-94) T/E/L 2.0L Turbo engine
Compression ratio 7.8:1
Standard compression 164 psi
Service limit 121 psi


Have you done a leak down test?

I was worried when I saw the numbers, but I have noticed that my dipstick no longer pops out, so either the engine is dying or my rings have fully sealed. I will do another compression test tomorrow. If the compression readings are still low I will do a leak down test.

Also my engine is on rebuild #3 according to the paperwork and cylinder walls. It could be #5 for all I know.

The only time my oil and coolant have mixed was right before my block blew up. I would be careful.

I would like to hear the story of what happened.:confused:

An update:
I having been driving the car for about a month now, with no serious cooling issues. I was going to resolve the thread as junk in the heater core, but I came home and it coughed up 3-4 oz of coolant in the driveway. It came from the overflow tube and temperature was normal.

It may have had too much coolant and is just leveling off or could be something else. I would add a little coolant after a run to compensate for trapped air bubbles releasing.

I smelled some of the spillage and detected that petroleum solvent smell. I am not finding any coolant in the oil. It may be some residue of whatever was in the cooling system giving it that smell. It smells like burned gasoline, or exhaust gas.

I will drain some coolant to check.

Is it possible the problem is not the engine but the turbo??
 
I cannot find the option to mark this thread as resolved.

The coolant leak has been fixed. I went to an AutoX and it started to leak more often through the overflow usually when the car would come to a stop. When I arrived home it was okay, but the next morning coolant was leaking from the Water pipe O-ring. When I would squeeze the radiator hose it would squirt out and if I removed the radiator cap it would start leaking continually.

To clarify it was an intermittent leak. It sat for 2 weeks cause I did not feel like working on it and during that time it would leak a few ounces of coolant and then it would seal again.

I did my very fast timing belt job having to replace the O-ring. The O-ring that was removed was not hard, and had not cracks, rips, or deformations. I did however compare it to the Made in Japan Beck/Arnley O-ring I replaced it with and the B/A ring was slightly thicker.

After I got it back running it did not leak driving around town. I had an AutoX last weekend and drove the car to New Orleans, made 10 runs on the AutoX pad and drove it back home and not a drop came out of the overflow, so I am calling the leak resolved, though the weird brown stuff is still a mystery.

So if you are having random coolant leaks from the overflow it may be your O-ring failing.
 
Man this is getting crazy. Since the last post I have changed the radiator hoses, and even used a bit of BARs Stop leak, but it is still leaking. It seems the problem is the coolant boils over after using moderate boost. It is like the turbo is boiling the coolant and making it come out of the overflow. I have heard these things can get red hot.

I would like Justin to chime at this point. Is it possible that the turbo is producing too much heat and causing this? It is a MHI Big 16g. I noticed that the turbine wheel looks a little damaged, and there is a small amount oil consumption. Is it possible the turbo is damaged and that is where the oil is mixing with the coolant? It is producing good boost, and solid pressure levels; spool seems good as well.

If we can understand this soon I can get an FP Green to replace it.
 
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Man this is getting crazy. Since the last post I have changed the radiator hoses, and even used a bit of BARs Stop leak, but it is still leaking. It seems the problem is the coolant boils over after using moderate boost. It is like the turbo is boiling the coolant and making it come out of the overflow. I have heard these things can get red hot.

I would like Justin to chime at this point. Is it possible that the turbo is producing too much heat and causing this? It is a MHI Big 16g. I noticed that the turbine wheel looks a little damaged, and there is a small amount oil consumption. Is it possible the turbo is damaged and that is where the oil is mixing with the coolant? It is producing good boost, and solid pressure levels; spool seems good as well.

If we can understand this soon I can get an FP Green to replace it.

Have you check the thermostat and water pump working properly?
it more like your coolant circulation is not good.
 
Well, I have been driving the car fo the past two weeks with no issues. For clarity: The coolant and oil are not mixing as is the case with a blown headgasket, but the prestone green coolant turns a high-brown color, as if the coolant is changing or something is being added to it.

There is a new Water Pump, Thermostat, and Mishimoto Radiator. I have driven the car over a 100 miles to an autocross, made around 12 passes, and driven back home with no issues at all. The only difference being I did not push the car hard. When the turbo is used at moderate levels, say, 1/2-3/4 throttle up to 5k-6k that is when coolant comes out of he overflow.

I can make a 2nd and 3rd gear pull up 5k and the car will behave normally, but if the turbo is used at high levels that is when I seem to have issues.

So I am trying to figure why so much heat is being generated that it is causing the coolant to overflow?
 
It sounds like you're lifting the head under boost and high load. The bare minimum I would do is change the head gasket. While under there, check for surface flatness on both block and head. If that checks out, replace gasket,and retorque the head studs in 3 steps in the proper torque pattern.
 
I bought a 19psi Mishimoto radiator cap and it doesn't leak anymore. I don't know what that stuff was in the system but I have one problem down. I guess there was more pressure than the stock cap could handle and it just let the coolant flow out. I did some hard driving and it didn't boil out.
 
I bought a 19psi Mishimoto radiator cap and it doesn't leak anymore. I don't know what that stuff was in the system but I have one problem down. I guess there was more pressure than the stock cap could handle and it just let the coolant flow out. I did some hard driving and it didn't boil out.

How much did that cap cost you?
 
Are you still getting the brown discoloration in your coolant? It could be that some of your system has rusted internally from improper coolant mixtures. Why not try flushing the entire system and refilling with fresh coolant and see if that helps
 
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