Ok, here's the backstory: I have a 2004 Disco II with 109k miles. 2000 miles ago or so I completely blew a head gasket towards the external side. Made a horrible noise. Heads were warped so had them skimmed and had the shop repair my HG.

About 1,000 miles later I got a misfire code on cold starts, Check engine light would flash 4 or 5 times then go solid. At about 1,500 miles after my HG job I noticed my coolant reservoir was pressurizing. Coolant reservoir would appear almost empty then once I cracked the cap would bubble back up.

I feared the worst (Cracked block, slipped sleeve or maybe a botched HG job).

Performed pressure test on the cooling system. All checks out fine. Did a chemical block test....passed with flying colors. Just yesterday I did a compression test and the results were pretty ugly:

Odd bank:
1 - 150
3 - 153
5 - 122
7 - 140

Even bank:
2 - 170
4 - 178
6 - 135
8 - 152

I'm assuming that new valves could take care of my compression, but would like a second opinion on that.

Also, the threads of my spark plugs were covered in oil. Thinking maybe the oil retaining rings on my pistons are shot. Who knows?

Anyway, I'm completely stumped on my cooling problem. Anyone have any idea at all WTF is going on?

Thanks!

 

Almost forgot, I also put in a new factory thermostat and bled the system several times. Waterfall noise in the glove box always comes back and reservoir repressurizes.

 

Take it back to the shop and have them double check their work, you are getting combustion gases into the cooling system.
Who knows why, but it should be under warranty.

 

How can I be getting combustion gases in the cooling system if the chemical test comes back ok?

 

What Spike said.... go back to the shop. If your problems started 1,000 miles after the HG job, then I doubt you have a bad block. I bet they didn't do the torque procedure right. Where did they get the HG kit from? Did they use new bolts?

Eric

 

Because the test is wrong (old, expired, stored incorrectly), or you did it wrong.

There is simply no other way to pressurize your cooling system other than compression/combustion gasses, and it's either coming through/around the head gasket, a crack in the head, or a crack in the block. Passing a pressure test just means it's not doing it cold. I have a motor on the stand that passes a compression test with flying colors. You can let it go all night and it's still holding pressure.

Put it in a truck and drive it for 15 minutes and it pukes all of its coolant out.

Pressure/block tests are presumptive. If they show a failure you can be positive it fails. If they don't show a failure it doesn't necessarily mean that there isn't one.

 

Your coolant test is wrong.
All the symptoms you are describing are classic blown head gasket/cracked head/block/slipped liner signs.

 

Well, then chemical tests are stupid and useless. The fluid was brand new and it doesn't take a rocket scientist to perform it. I checked about 5 different times starting when it was stone cold and then several times while leaving the engine running for about 30 minutes. I even put the reservoir cap back on and waited until it was good and pressurized, then popped the cap and quickly ran the chemical test again....still blue as the sky.

Another thing to mention...I checked the spark plugs and found them to all be black, not "steam cleaned" as if there were coolant leaking into the cylinder.

Feel like I'm living in the Twilight Zone.

 

Black with soot or carbon?
Or black with some other substance?

 

"Almost forgot, I also put in a new factory thermostat and bled the system several times. Waterfall noise in the glove box always comes back and reservoir repressurizes."

I believe the Waterfall Noise is a classic description of the coolant not being bled correctly. Did you try all the typical tricks- lifting front end, raising the exp. tank, etc? Is it loosing any coolant? If it is not loosing any, why is the tank empty and not showing signs of combustion gas?