Head gasket or turbo charger?

mgjonesin · Post by **mgjonesin** » 13 Oct 2010, 09:52

I'm loosing about one cup of anti-freeze a month. There dosen't seem to be any leaks. There is a small amount of white smoke starting the car after it has sat overnight. It only lasts a second. I'm going to check the plugs. I'm not sure I wan't to do a pressure check for fear of making it worse. Where can I test the anti-freeze for exhuast gasses? Any other suggestions?

Thanks,

Jon

Post by **JDS60R** » 13 Oct 2010, 10:05

Test the coolant when cold. It is a chemical test you can but online or at Napa. Sounds like a pinhole in the ehad gasket. Get it fixed now. They let go suddenly and cost many a new block. If its fixed while only a pinhole its only the cost of gaskets and machining if needed.

mgjonesin · Post by **mgjonesin** » 16 Oct 2010, 12:10

I removed the sparkplugs and none of the pistons or plugs showed signs of coolant in the cylinder and none were "bright" or "clean". However, I did notice that the tubes to the pax side turbo were super clean and the drivers side were oily. I think that the missing coolant is leaking through the coolant jacket in the driver side turbocharger and steam cleaning the intercooler tube. What do you think? Anyone know about turbos with cracked water jackets?

Post by **JDS60R** » 19 Oct 2010, 22:49

If the turbo center housing had cracked (rare) then the coolant would have entered the cylinders after the inter-cooler and cleaned the pistons. If a pinhole leak in the head gasket does occur it usually cleans the edges of the piston and can not be seen without a boroscope or the head removed.

When will you test for exhaust gases?

You might also want to get some leak dye for the coolant and a light.
The oil cooler and rad drain will commonly leak . The oil cooler needs better clamps and the the rad drain is not always manufactured smooth as to allow its o ring to seal.

mgjonesin · Post by **mgjonesin** » 23 Oct 2010, 20:01

I just got back from being out of the country. Before I left I called NAPA and the dipsticks there had no idea what kind of coolant test I was asking for! Their online cataloge is completely worthless! I am waiting for a weekday so the I can contact NAPA corporate so they can tell me what part number to order for testing the coolant.

Can the coolant leak into the exhaust side of the turbo?

Post by **JDS60R** » 23 Oct 2010, 20:27

It can leak into the exhaust side but would be vaporized.

BK 700-1006 "Combustion Leak Block Tester" - Cost ~$49.00

http://www.napaonline.com/Search/Detail ... 0006398563

Cost effective
https://www.amazon.com/Lisle-Combustion- ... sim_auto_6

Really nice one you can use over and over - use Matt's amazon link to buy it !!!!
https://www.amazon.com/UVIEW-560000-Comb ... B000NPDL76

Always start with a pressure test -its the cheapest and easiest.
Can you upload pics of the plugs and tell us what color the piston tops were. I am really second guessing here with limited info. A few pics could really help.

mgjonesin · Post by **mgjonesin** » 27 Oct 2010, 19:42

Got the exhaust gasses test. The fluid didn't change colors, so no exhaust gasses in the coolant. Next I'll check the intercooler lower hose, just in case it's an intercooler leak. After that I guess I'll pull the turbos.

Jon

Post by **JDS60R** » 27 Oct 2010, 20:15

Glad the head gasket is ok - now its time to pressure test and then dye test the coolant.

These small leaks tend to occur at the oil cooler or the rad drain

Keith19851985 · Post by **Keith19851985** » 22 May 2018, 08:39

Hey I have new hg on turbo 850 Volvo I have 125 compression on all cylinders pistons don’t look clean there’s tons of white smoke reservoir fills up could my turbo be mixing fluids and putting exhaust gas on reservoir?

Post by **SuperHerman** » 22 May 2018, 14:22

Easy items first. You can rent the Combustion block tester (for free) at Autozone. Caveat is you need to buy it and return it (normal Autozone policy) and then you buy the test fluid which you have to buy regardless.

First how many miles on your car? Your white smoke issue may be your valve stem seals showing their age. The symptoms regarding start up smoke is consistent with this condition. Oil seeps down past the seals and accumulates in the piston combustion area as the car sits. As the amount is minimal because the system is not pressurized and their are easier paths to the oil pan it is just a slight puff at start up.

As to your coolant leak - put dye in the system and use a black light to find the leak - pressure test would also be great. Pressure testing should not make matters worse as one pressurizes at the same level that the system is designed for - so under load you are subjecting the system to what the combustion cycle does. The coolant cap should release excess pressure by design if it gets too high.

Regarding the turbos, having just rebuilt these on my 2004 2.9t I doubt they are cracked or the source of your problem. No moving parts and the seal is threaded (the oil lines have a gasket). The turbo is cast iron and from my observations a very unlikely source of a leak under normal conditions on an older car - casting irregularities would have manifested themselves many years ago. If they have recently been worked on maybe but looking at the turbo cartridge in my hands - I just do not see it.

Let us step back - the two Mitsubishi TD03 used in the XC90 are oil lubricated and coolant cooled. If one or both of the turbos were leaking coolant due to an internal crack it would have three places to go. 1) Into the oil - you would see this in your oil and it would always smoke and most likely throw a misfire code if severe enough; 2) outside the turbo - you would see signs of cooked coolant dust or the actual coolant dripping on the ground based on the amount of coolant you are losing or the dye/black light will catch it; or 3) into the inlet or outlet pipe and you would see it smoking all the time. Under combustion everything expands so the condition should be most pronounced after the car warms up.

One other possibility regarding coolant loss - I am not sure on this though - maybe your oil cooler is failing as I think it is coolant cooled and it is possible (at least on other cars I own) that the coolant is mixing with the oil at that location. Again - the oil should show some signs of this and it would smoke all the time.

I would say you have three issues 1) A coolant system leak; 2) aging valve stem seals (smoke caused by intake valve stem seals) and/or possible PCV issues (positive system pressure could cause this - but mainly under combustion); and 3) aging turbos. (I rebuilt mine because the driver side tubes were showing signs of failure reflected in oil in the runner.) When the turbos get bad enough the car will smoke all the time as more and more oil pass through the bearing/bushing/seal and enter into the combustion process. I have a write up on the removal/install process on this forum - just look under my posts.

As to the valve stem seals being the source of the start up smoke - how oily were your spark plugs and how did bank 1 plugs (pass side 1-3) compare to the bank 2 plugs (driver side 4-6)?

Poster regarding his 850 - sounds possible but I don't understand exactly what you are saying. What do you mean "reservoir fills up"? You need to provide more detail. I will state though many times after a HG job the engine will smoke for sometime as the coolant and oil in the exhaust burn off. It should be getting better the longer the car runs. A failing turbo will cause smoke, as stated above, as oil is getting into the combustion process. If you are asking if coolant is entering into the combustion process via the turbo - your car uses a single larger Mitsubishi TD04 which is design wise just a larger version of the TD03 - so as I said above and for the same reasons doubtful. If you are saying that you did a block test and you are getting signs of coolant in your combustion gas I would say you still have a head gasket problem or possibly the engine oil cooler as mentioned above. Are you loosing any coolant or oil or is either showing signs of mixing? Is the car overheating - coolant reservoir bubbling?