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I appear to have a condensation issue with my ls1. It doesn't appear to be antifreeze, but whenever I pull the oil filler cap It's dripping wet and I'm getting a ton of white milky gunk in the pcv system (and probably other areas).
Assuming it's not a coolant leak, what could be causing it, and what are my fixes?
The coolant level appears to be fine. I flushed and changed it back in april and its still (roughly) in the same spot? Its tough to read the dipstick
I did however see a bunch of brown gunk on the coolant dipstick, not sure if its old dex-cool left over but here's a pic after I wiped it on a paper towel:
As for driving, my commute to work is roughly 30 minutes, so plenty of time for the car to reach operating temp.
i had something similar happen to me a few years ago on my truck. it would take a few weeks to a month before i noticed any discernible drop in coolant level, so it was a slow leak. i thought it was an intake gasket (from my sbc days - this was my first ls) and once i figured out i had a dry intake, i thought it was a water pump. as it turned out, it was neither.
Since its been 7 months and 0 coolant drop I think you're fine. Have you tried to look at the coolant in the radiator (don't do it when the engine is hot)? Does your car have a factory power steering cooler?
I still don't know exactly where it was coming from. the gaskets looked like they may have been leaking. i swapped heads and never had the originals pressure tested to see if they had cracked.
jb, i don't see how you can say that he's probably fine.
by his own description: 'oil filler cap It's dripping wet and I'm getting a ton of white milky gunk in the pcv system.' What is the pcv system? positive crankcase ventilation. that means that the 'white milky gunk' is in the crankcase & thereby mixing with the oil. therfore, i'd say he should probably stop driving it until he gets it fixed.
at the very least, go pull the valve covers off to see how bad it is. have you changed the oil since you've noticed it? how did it look?
I meant it's probably not coolant. If it was a head gasket I would think after almost 6k miles (40 miles/day, 5 days a week for 7 months) there would be a loss of coolant. That's why I asked if it has the stock power steering cooler, as those can leak into the coolant.
I meant it's probably not coolant. If it was a head gasket I would think after almost 6k miles (40 miles/day, 5 days a week for 7 months) there would be a loss of coolant. That's why I asked if it has the stock power steering cooler, as those can leak into the coolant.
True about the power steering cooler... that would explain the cruddy coolant, but that still doesn't explain the moisture in the pcv system.
When I said i had the white substance in my PCV system, it was seen when I first bought the car. I pulled the valve covers and the TB, and the upper left corner of where the TB meets the intake (as you're looking at the intake, I think it's the PCV connection) was gummed up with the white crap. I cleaned it out, but haven't had a chance to pull the TB to see if it's come back. I am seeing some (but not a lot) on my oil filler tube. Did an oil change on wednesday, oil came out black and clear of any white bits or sludge.
I have looked at the coolant in the radiator, it's orange and clear (thinking it was just old dexcool on the dipstick). I do have a factory steering cooler.
I did the oil change at my gfs dads place, I may go back and run the old oil through a filter (like coffee filter or something) and see if anything stays on the filter.
As for where the coolant is on the dipstick, surprisingly enough it appears that when cold it's reading full hot. I can confirm that it's roughly in the same area as back in july or so when I last checked.
I'll see about the valve covers this weekend if time allows. When I pulled them back in April, they appeared to be fine, PCV runners were a bit gunked but not with white sludge if i remember correctly.
And unfortunately I can't really afford to stop driving the car, it's my only vehicle.
Edit: For someone with intermediate mechanical experience, is pulling the heads do-able in a weekend?
Last edited by HappySalesman; 11-15-2014 at 03:58 PM.
I'll see about the valve covers this weekend if time allows.
And unfortunately I can't really afford to stop driving the car, it's my only vehicle.
Edit: For someone with intermediate mechanical experience, is pulling the heads do-able in a weekend?
If it were me, i'd make time to check it out. if you can't afford to stop driving the car, you sure as hell don't have time to swap an engine.
i wouldn't bother straining the oil. mine never showed signs of clumps nor any milkshake discoloration - nothing. the only thing that i could see was the dye under the light (other than the white gunk on the valve cover).
as long as you don't run into broken bolts & have all your parts, you can probably r&r the heads in a day. i did a heads/cam swap in a weekend 1st time through on a 5.3 ls a few years ago.
Good point. I'll pull the covers this weekend (my weekends are tue-wed) and see what I see, if I see a lot of white milky gunk... guess it's time to check the head gaskets.
When I said i had the white substance in my PCV system, it was seen when I first bought the car. I pulled the valve covers and the TB, and the upper left corner of where the TB meets the intake (as you're looking at the intake, I think it's the PCV connection) was gummed up with the white crap. I cleaned it out, but haven't had a chance to pull the TB to see if it's come back. I am seeing some (but not a lot) on my oil filler tube. Did an oil change on wednesday, oil came out black and clear of any white bits or sludge.
I have looked at the coolant in the radiator, it's orange and clear (thinking it was just old dexcool on the dipstick). I do have a factory steering cooler.
I did the oil change at my gfs dads place, I may go back and run the old oil through a filter (like coffee filter or something) and see if anything stays on the filter.
As for where the coolant is on the dipstick, surprisingly enough it appears that when cold it's reading full hot. I can confirm that it's roughly in the same area as back in july or so when I last checked.
I'll see about the valve covers this weekend if time allows. When I pulled them back in April, they appeared to be fine, PCV runners were a bit gunked but not with white sludge if i remember correctly.
And unfortunately I can't really afford to stop driving the car, it's my only vehicle.
Edit: For someone with intermediate mechanical experience, is pulling the heads do-able in a weekend?
I would doubt its the head gasket if your not loosing coolant, how cold is it where your at right now are you sure its not condensation from the cold weather?
Good point. I'll pull the covers this weekend (my weekends are tue-wed) and see what I see, if I see a lot of white milky gunk... guess it's time to check the head gaskets.
Ensure you've got new gaskets and head bolts on hand, then start tearing things apart as soon as you can Monday night with the goal removing the throttle body, intake, and coils. You can then hit the ground running Tuesday morning with the goal of having everything done Tuesday night. This way you have Wednesday should you hit any snags on Tuesday.
Doing it during the week also gives you the ability to run to a parts store later than on the weekend. It would also guarantee the ability to receive a part overnight if you needed something unavailable locally.
Lastly, I'd ditch that stock power steering cooler while you've got all that stuff apart.
I agree that a head gasket is unlikely if there has been zero loss of coolant in the last 7 months/6k miles, and if the coolant and oil both look fine.
I've seen a ton of that milky crap on the oil fill cap before on some of my own cars when they had been used for lots of short trips in cold weather.
Do you have a colder-than-stock t-stat and/or fan settings? If so, even over a long drive the engine may not be getting as warmed up as it needs to be.
I also agree about ditching the PS cooler. This is a problem waiting to happen.
Based on what is known so far, I certainly wouldn't be pulling the engine apart for a head gasket swap when the oil and coolant both appear clean with no change in level after so many months. You could pressure test the cooling system as another check, but the first step in this case shouldn't be ripping things apart IMO. I'd also suggest sending in an oil sample for a UOA before any thought of pulling the heads for a problem that may not exist.
I pulled the valve covers, aside from a small amount of contamination on the passenger side valve cover I didnt see anything anywhere else. My only other guess is perhaps a bad oil filler cap allowing moisture in. Otherwise im going to keep an eye on the coolant level and see if I ever see it drop.
what little water you are seeing under the oil fill cap is normal. 30 minutes is not long enough, while coolant temp can reach 190° in about 15-20 minutes depending on outside temperature your oil temperature greatly lags. i have an oil temp sender in my oil pan on mine, and after my 30 minute drive to work this time of year where it's between 32°-50°F in the morning by the time i get to work which is 17 miles, my oil temp is just getting to around 140°F. and oil temperature will stay colder longer if it's highway miles you are doing.
Its either normal or both of my Z28's have the same issue as you do. I have noticed it with my green Z for all 15 yrs that I have had it. As soon as the weather turns to rain or snow I start seeing some condensate on inside of cap. I am not going to sweat it.
Its either normal or both of my Z28's have the same issue as you do. I have noticed it with my green Z for all 15 yrs that I have had it. As soon as the weather turns to rain or snow I start seeing some condensate on inside of cap. I am not going to sweat it.
Makes sense to me, there will be some moisture in the oil crankcase no matter what you do. If the outside of the cap is significantly colder than the crankcase, you'll see condensation. It's like a cold beer in summer.
11-11-2014, 05:55 PM
Condensation?? 
