Hey all, the thread title kind of speaks for itself. Let me try to explain the problem with my car in a very detailed and easy to understand manner. I got the car about 5 months ago. The car runs great. Temperatures stay at about 180-170 while driving and tend to heat up in traffic or standstill. The problem with the car is that it's using coolant somehow. My coolant loss tank gets lower.. and lower. I usually overfill the reservoir so I make sure I have enough coolant for my trip because it uses some as I've stated. The previous owner of the car that I contacted (I bought the car from the dealer though) he stated that had the same problem with it and said that when he removed the valve cover that it contained a mix of coolant. He said that he had the head gasket changed along with the head resurfaced. He said he pulled the valve cover after the head gasket replacement and the valve cover still have coolant in it, according to him. He told me that he used some method of a torch on the oil and the coolant would do something?? He referred to it as a "old time mechanic trick". I'm pretty mechanically inclined, but I need this car for college now and I can't afford to take the time to do the work myself. However I don't know anything really on these cars (I'm more of a old school V8 muscle car mechanic). I have had the car at the local Chevy dealer (not the one I bought it from) and had it pressure tested. The mechanic said it only lost 4 pounds of pressure over a almost 2 hour period and stated that was a small leak and said that could be the gauge not making a great connection even. They looked for leaks underneath the car. They pulled the spark plugs and looked in there too see if they could see it leak, and they did not. I got the dye test from O Reily's and performed the dye test with the fluid that changes color when combustion gases are present. I performed the test with the beaker over the overflow reservoir with the car running and used the ball pump to pump the gases up to the fluid. The Chevy dealer really didn't know what to tell me they are stumped. The previous owner was stumped. And now I'm stumped. I pulled the oil cap off today and it "looked" like possibly there was a little coolant mixed with the oil that was present on the cap, but I'm not sure. (I will post a picture of the caps oil and see if someone can confirm). So all in all, does anyone have any ideas?? Help would be greatly appreciated.

Thanks,

CW

 

What year is your car? Sounds like the famous porous block problem

 

Sorry I guess my so called "detailed" post forgot to include some basic info lol. It's a 2006. "From what I've heard" the porous block was not an issue with 2006, but again that's just "what I've heard". Do you have any comment on the picture of the oil cap as to whether that looks like coolant mixed in with it or not? Thanks for your reply.

 

Sounds like porous block or turbo buring the coolant.

 

oh lol. I thought you had an LNF

 

When you say they looked for leaks under the car, do you mean they checked all the coolant connections including the main coolant tube from the water pump and the bleeder screw on the water pump?

 

ECaulk, I'm not exactly sure. "I think" they meant that they just lifted the car up on the lift and looked visually at things they could see and looked for leaks. If I'm not mistaken, on these cars you have to remove that little inspection plate on the passenger side of the motor to view the water pump? Again, I do not know much about these cars and I am not exactly sure where the tube you are referring to is located. Any comment on the pic I posted as to whether you think it looks like coolant mixed or not? Thanks for your reply

 

There is a coolant tube that runs behind the motor, right below the exhaust manifold. there is a screw that allows you to drain your water pump. it might be leaking from that. I know mine had a small leak there after I put my ZFR on and I had to go tighten it back down.

 

Lol reason why I asked for the year just to make sure

 

No need to remove the inspection plate. If you can get under the car and look up towards the exhaust manifold you'll see a larger tube bent down below the header, check both ends for evidence of coolant leaks.

 

Have you checked your oil level? From what i can see in the pic, it does look a bit milky. I believe there is a company that you can send an oil sample to that will test to see if there is coolant in it. Do the simple things that ECaulk suggested first tho.

 

All right I'll see if I can give that a look. But question if that was leaking then how would coolant be present in the valve cover due to that? Again I haven't confirmed the coolant in the valve cover, that's just what the previous owner said. I have attached a picture of the oil cap with some oil on it to see what others think as to whether it's mixed with coolant or not.

 

Oil level is good and the oil on the dipstick looks new ( the previous owner said that the dipstick wasn't showing coolant in it, only what was in the valve cover "again just what he said").

 

I wouldn't get to worried about the little bit on the oil cap. The previous owner could of been looking at condensation that had occurred in the valve cover and just directly assumed it was a coolant leak.

 

ECaulk, that is true, and he did mention that it wasn't condensation, again "what he said". What irritates me is that he already had the head gasket replaced, but the problem is still ongoing. A shop will charge me a thousand dollars, I'd say, to replace the head gasket and if the previous owner has already done that (whether it was done correctly or sufficiently or not is up in the air) then I feel like I'm taking a gamble on it and potentially fixing something that may or may not be the culprit. I'm loosing coolant we do know that. I do not see any signs of dripping. The car had a ZZP heat exchanger/radiator. I just don't know where to start? Maybe get a oil sample test done to verify that there is indeed oil present?

 

*has a ZZP heat exchanger not had*

 

The heat exchanger system is seperate from the engine coolant so i wouldnt focus on that. Though it isnt common for your year it could be possible that you have a cracked sleeve.

 

Wait a min, what side is the coolant res on that you're having to add coolant to?

 

Coolant reservoir tank on the driver side

 

The one you can see in the far right top of this picture. I know it's the correct one. I also know the supercharger coolant system is a separate system.

 

Top right of this picture

 

Just want to make sure everyone was on the same page.

 

ECaulk, it's all good. Where would you start on trying to figure out this problem?

 

Given there was a pressure loss, I'd look for leaks. One quick dirty method to find out if it's a head gasket or cylinder wall, with a completely cold engine pop the hood, start it, let it idle for about 30seconds, then rev it to 2k to 2.5k for 30seconds to 1 min. Shut it off then remove the cap. If you have a pressure release there is a leak in the head or cylinder walls, no pressure release your issue is most likely not engine internals related.

 

Here's a picture of the dye after the test.