What Fluid is This - Green (Maybe Yellow)
#1
What Fluid is This - Green (Maybe Yellow)
Cayenne V6 with liquid cooled alternator.
I have what appears to be a green fluid on various parts of the engine (been sitting for several days and its still liquid so not its not evaporating). Its probably finding its way to the belt and throwing it around? There is a green fluid on the alternator and the compressor has some green fluid on the inner cavity of the pulley. There is some other fluid substance on other parts, but not enough to identify a color (and the driver side beauty covers are slick). On the bottom, its dripping just a little bit...but whats weird is that appears to be more yellow than green.
A/C Refrigerant? - I have had a lot of problems with the AC, but thought I finally had it working. It still seems to be blow cold air (but could still be leaking). I wouldn't have normally thought this, but on a postmortem of my last compressor, I saw a green fluid in one of the cavities. Not sure if that is the oil (normally yellow), mixed with refrigerant or something. But maybe the new compressor (a cheap rebuild) is leaking at the seal...which could explain why the inside of the pulley has the most prominent green fluid. Seems like it would be quite hard to get fluid in the inner rim of that pulley unless that is the source.
Power steering fluid - There is a leak somewhere and its throwing it around. I had the rack replaced a few years back and not sure what they use, but it was a bit low when I checked it. I use CHF-11S, which is green. But its just weird that its made its what into the compressor pulley but not the power steering pump pulley...or maybe not that weird.
Coolant? - I always use Porsche (pink) but I know there is a green version that is equivalent and maybe when it was serviced last they used that (local shop). So perhaps is coolant leaking from the alternator (its a rebuild I got from eBay) and its the water cooled version (sort of odd - most are air cooled). But I thought coolant would dry up after a few days and not still be liquid?
Brake Fluid - This is yellow and I didn't notice the level had dropped. But this is the only yellow fluid consistent with what I found at the bottom.
----
So any advice? I was hesitant to clean it and just have the shop look at it, but now I am thinking maybe I can clean it up and then do a couple tests.
Test 1: Run the A/C hard for a while and see if anything new comes out.
Test 2: Continually move the wheel (while parked) and see if anything new comes out.
I think its most like the PS fluid or A/C refrig/oil so maybe one of those tests can help shed light. Or perhaps its even multiple failures.
Does there happen to be a way to test a fluid directly because of its make-up? Like a litmus test or something?
I have what appears to be a green fluid on various parts of the engine (been sitting for several days and its still liquid so not its not evaporating). Its probably finding its way to the belt and throwing it around? There is a green fluid on the alternator and the compressor has some green fluid on the inner cavity of the pulley. There is some other fluid substance on other parts, but not enough to identify a color (and the driver side beauty covers are slick). On the bottom, its dripping just a little bit...but whats weird is that appears to be more yellow than green.
A/C Refrigerant? - I have had a lot of problems with the AC, but thought I finally had it working. It still seems to be blow cold air (but could still be leaking). I wouldn't have normally thought this, but on a postmortem of my last compressor, I saw a green fluid in one of the cavities. Not sure if that is the oil (normally yellow), mixed with refrigerant or something. But maybe the new compressor (a cheap rebuild) is leaking at the seal...which could explain why the inside of the pulley has the most prominent green fluid. Seems like it would be quite hard to get fluid in the inner rim of that pulley unless that is the source.
Power steering fluid - There is a leak somewhere and its throwing it around. I had the rack replaced a few years back and not sure what they use, but it was a bit low when I checked it. I use CHF-11S, which is green. But its just weird that its made its what into the compressor pulley but not the power steering pump pulley...or maybe not that weird.
Coolant? - I always use Porsche (pink) but I know there is a green version that is equivalent and maybe when it was serviced last they used that (local shop). So perhaps is coolant leaking from the alternator (its a rebuild I got from eBay) and its the water cooled version (sort of odd - most are air cooled). But I thought coolant would dry up after a few days and not still be liquid?
Brake Fluid - This is yellow and I didn't notice the level had dropped. But this is the only yellow fluid consistent with what I found at the bottom.
----
So any advice? I was hesitant to clean it and just have the shop look at it, but now I am thinking maybe I can clean it up and then do a couple tests.
Test 1: Run the A/C hard for a while and see if anything new comes out.
Test 2: Continually move the wheel (while parked) and see if anything new comes out.
I think its most like the PS fluid or A/C refrig/oil so maybe one of those tests can help shed light. Or perhaps its even multiple failures.
Does there happen to be a way to test a fluid directly because of its make-up? Like a litmus test or something?
Last edited by AeroStress; 03-20-2024 at 01:14 AM.
#2
Race Car
The PAG oil used in R134 A/C systems is miscable with water, CHF11S is not.
#3
Three Wheelin'
Power Steering fluid is green but usually looks fairly dark after some use. A common forgotten item to have flushed. You can use CHF11S or CHF202. 202 is the newer fluid but has backwards compatibility.
#4
The PS pump and rack were replaced a couple years ago so I guess its flushed out? But I don't know what they used. Is 202 more of a yellow? My CHF11S is bright green.
I decided to clean it out this morning and here is a picture of the bright green color from before I cleaned it out. This was on the airbox...presumably from the fluid getting caught in the belt and being slung around. I just used this since it was the best picture of the bright green.
After I cleaned it out really good (lots of sludge), I drove it 20 miles with the AC off. Not sure if that matters since the pulley is still active (though the compressor shouldn't kick on). Anyway, after that...there was fluid spatter on the bottom plastic panel (fluid getting thrown from the belt probably). The compressor pulley didn't seem to have anymore of the green though. However, the PS pump had some fluid on it as shown here. Perhaps its the fitting? But that fluid is more yellow in color.
And of course its possible its multiple that just coincidentally showed up at the same time. But there isn't enough fluid to collect and see how it reacts with water. It seems to be making its way the belt and then becomes spatter.
I decided to clean it out this morning and here is a picture of the bright green color from before I cleaned it out. This was on the airbox...presumably from the fluid getting caught in the belt and being slung around. I just used this since it was the best picture of the bright green.
After I cleaned it out really good (lots of sludge), I drove it 20 miles with the AC off. Not sure if that matters since the pulley is still active (though the compressor shouldn't kick on). Anyway, after that...there was fluid spatter on the bottom plastic panel (fluid getting thrown from the belt probably). The compressor pulley didn't seem to have anymore of the green though. However, the PS pump had some fluid on it as shown here. Perhaps its the fitting? But that fluid is more yellow in color.
And of course its possible its multiple that just coincidentally showed up at the same time. But there isn't enough fluid to collect and see how it reacts with water. It seems to be making its way the belt and then becomes spatter.
Last edited by AeroStress; 03-20-2024 at 09:44 PM.
#6
Burning Brakes
Basic troubleshooting:
Does the A/C work? If you're losing that much oil, the refrigerant should be long gone.
What's the level in the PS reservoir?
What's the brake fluid level in the master cylinder?
What's the level in the coolant expansion tank?
Not sure what color coolant was used by last shop? -->> What color is the coolant in the expansion tank?
Does the A/C work? If you're losing that much oil, the refrigerant should be long gone.
What's the level in the PS reservoir?
What's the brake fluid level in the master cylinder?
What's the level in the coolant expansion tank?
Not sure what color coolant was used by last shop? -->> What color is the coolant in the expansion tank?
#7
Addict
Rennlist Member
Rennlist Member
Certainly looks like it could be AC oil plus leak detection dye, you could get a UV light and compare how bright that fluid is with your other fluid options.
Trending Topics
#8
Looks like PS fluid to me. Stains are also on the PS pump. Is PS fluid level dropping? That is a sizeable leak. Probably around the shaft seal.
If you were leaking that much PAG oil out of refrigerant (if there is that much in there to begin with), your compressor would've long locked up by now.
Just because the PS pump was replaced doesn't mean the new one is any good. Was it new OEM, or reman?
If you really want to check fluid color, get a paper towel and take swabs at different places to compare against same background color.
If you were leaking that much PAG oil out of refrigerant (if there is that much in there to begin with), your compressor would've long locked up by now.
Just because the PS pump was replaced doesn't mean the new one is any good. Was it new OEM, or reman?
If you really want to check fluid color, get a paper towel and take swabs at different places to compare against same background color.
#9
Some more data and info:
- I was able to collect enough fluid (using a plastic razor blade) from the bottom of the shield and mix it with water. It did not become homogeneous (insoluble).
- I put a small bit of rag (along with a zip tie) around the portion of the pump that I thought was the source. Ran again for a while and this was not the source.
- Next trial is a bit of rag around another section of the PS pump that might be the source and will see again after I run it for a bit.
- Brake fluid is good.
- PS fluid wasn't full before so I topped it off a week ago or so. Since then, I have noticed a significant drop.
- AC is still working.
- There definitely was some dye in the AC system before but the last time I pulled a vacuum on it and added refrig back, I did not add dye. I don't know if there could still be residual though.
- I ordered some dye, a dye injector, and the UV light yesterday actually.
- The color in coolant reservoir is brown/pinkish...I did add a half gallon of water and half gallon of coolant recently. But that somewhat normal to do every year or two.
Should be able to get to the bottom of this eventually. As far as the taste test goes...that might be quite a good test! But, I am hesitant to do that to myself, ha.
- I was able to collect enough fluid (using a plastic razor blade) from the bottom of the shield and mix it with water. It did not become homogeneous (insoluble).
- I put a small bit of rag (along with a zip tie) around the portion of the pump that I thought was the source. Ran again for a while and this was not the source.
- Next trial is a bit of rag around another section of the PS pump that might be the source and will see again after I run it for a bit.
- Brake fluid is good.
- PS fluid wasn't full before so I topped it off a week ago or so. Since then, I have noticed a significant drop.
- AC is still working.
- There definitely was some dye in the AC system before but the last time I pulled a vacuum on it and added refrig back, I did not add dye. I don't know if there could still be residual though.
- I ordered some dye, a dye injector, and the UV light yesterday actually.
- The color in coolant reservoir is brown/pinkish...I did add a half gallon of water and half gallon of coolant recently. But that somewhat normal to do every year or two.
Should be able to get to the bottom of this eventually. As far as the taste test goes...that might be quite a good test! But, I am hesitant to do that to myself, ha.
Last edited by AeroStress; 03-21-2024 at 02:57 PM.
#10
Three Wheelin'
#11
At a basic level, isn't the refrigerant a gas when not pressurized? And wouldn't a gas leak out before oil? In other words, if the AC is working, it seems it might be impossible to be leaking AC oil?
#12
Burning Brakes
Also, adding 1 gallon to the cooling system every year or two isn't normal. I did my coolant pipes 9 years ago and haven't needed to top up the coolant since.
I would suspect coolant, but you said it's not green. Spraying coolant also leaves white specks on the black hood insulation.
That leaves your PS pump as the main suspect, especially since you said there's been a significant drop in a week.
#13
That's why I said (up above) the refrigerant would be long gone.
Also, adding 1 gallon to the cooling system every year or two isn't normal. I did my coolant pipes 9 years ago and haven't needed to top up the coolant since.
I would suspect coolant, but you said it's not green. Spraying coolant also leaves white specks on the black hood insulation.
That leaves your PS pump as the main suspect, especially since you said there's been a significant drop in a week.
Also, adding 1 gallon to the cooling system every year or two isn't normal. I did my coolant pipes 9 years ago and haven't needed to top up the coolant since.
I would suspect coolant, but you said it's not green. Spraying coolant also leaves white specks on the black hood insulation.
That leaves your PS pump as the main suspect, especially since you said there's been a significant drop in a week.
- If its coolant...I think it does evaporate and leave those specs like you said. I have had coolant leaks before and it doesn't seem like that is it. However, maybe there is a coolant leak INTO the engine, causing it to be required to be added every year or two..not sure about this.
- When mixing the green fluid with water, it is not homogenous...same as if I mix CHF11S from the container with water. So yeah, I am thinking PS as well. But I have also done 2 tests now where I wrap the fitting in cloth and then run it. Both of the cloths have been dry, yet I still get fluid at the bottom (its spatter so getting kicked off the belt I think). I can only see one other obvious place to do the wrap test...so that is next. After that, not sure where the heck it would be coming from.
- Oh, also...is it safe the assume the coolant from the reservoir gets mixed with the coolant flowing in the systems...or could they be separate? And hence possibly two different colors?
Last edited by AeroStress; 03-21-2024 at 06:34 PM.
#14
Only time I had to add coolant to my vehicle was when the coolant vent line under the intake manifold failed and started leaking slowly over time- was a high speed turn on an offramp that triggered the low coolatn warning at which time I discovered my V-valley was a auxiliary coolant storage.
#15
OK...the plot thickens. The color from the coolant reservoir is pink...so if that does mix with the system, thats not it. The color from the PS reservoir is brown/yellow (and NOT green...even though I added a bit of CHF11S, which is green). I put rags on ports of the PS pump and and its not coming from those connections or lines (they were clean after running it). And those lines run away from the belt and where totally dry the farther they got from the belt.
So that leaves the AC compressor as a probably culprit (though it seemingly doesn't make sense that the AC would still work). However, this is a rebuild from eBay about 6 months hold and who knows if its junk (I was taking a chance since I fried my prior compressor via AC stop leak...thought it DID seem to fix the nasty evaporator leak...which is a nightmare to swap out). The only collection of fluid that I can see is that bright green and the only place I see it is near the compressor now that everything has been cleaned off. On the V6, its right between the alternator and PS pump so its hard to get close to though. Tomorrow I will do the UV and dye test on the AC I guess because its just not making sense that its the PS fluid...its not even close to bright green in the reservoir.
Heck, it could still be multiple leaks too...just that one is showing up more than the other and clouding thing.
So that leaves the AC compressor as a probably culprit (though it seemingly doesn't make sense that the AC would still work). However, this is a rebuild from eBay about 6 months hold and who knows if its junk (I was taking a chance since I fried my prior compressor via AC stop leak...thought it DID seem to fix the nasty evaporator leak...which is a nightmare to swap out). The only collection of fluid that I can see is that bright green and the only place I see it is near the compressor now that everything has been cleaned off. On the V6, its right between the alternator and PS pump so its hard to get close to though. Tomorrow I will do the UV and dye test on the AC I guess because its just not making sense that its the PS fluid...its not even close to bright green in the reservoir.
Heck, it could still be multiple leaks too...just that one is showing up more than the other and clouding thing.