Same gunk but a darker background. The only reason mine doesn't look like yours is my valve cover is nearly new. I just hope the engine is still in one piece after running partial coolant as oil. Good grief. Not going to bother with any further inspections. 203k miles and I have the 706 Battery heads. It is time to take care of this. Thank you for pics.
2003 Tahoe coolant system leak or head gasket leak?
- Thread starter tomloans
- Start date
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Same gunk but a darker background. The only reason mine doesn't look like yours is my valve cover is nearly new. I just hope the engine is still in one piece after running partial coolant as oil. Good grief. Not going to bother with any further inspections. 203k miles and I have the 706 Battery heads. It is time to take care of this. Thank you for pics.
This is very frustrating to say the least. Any input, insight, anything please. I will glean info. I just put 17 PSI on the pressure tank and it held forever. No loss in pressure. This is very confusing and I don't want to go through replacing the heads for no reason at all! Any input will be appreciated greatly.
What do the heads and rockers look like? Any real clean spots on them? Pics?
Any progress or update on a UV dye test, or combustion gas test on the coolant?
iamdub
Full Access Member
It's common that it only leaks when hot. From my experience, either you're running some really crappy oil or that's the beginning stages of the coolant/oil mix, meaning you caught it early. Honestly, if it runs great, has normal oil pressure and it's not full of black gunk, I'd say you're golden. Replace the heads and keep truckin'.
Can we get a good pic of the springs/rockers/etc.? Have you looked at the areas around head bolts, particularly between #3 and #5?
My brother's truck had 181K when I tore into it. It now has about 220K. Never opened up anything on the bottom end other than removing the oil pan to clean it and the rotating assembly. I did remove the cam to clean it and inspect the lobes and bearings. Slid it right back in. I pretty much did the same to mine at 200K, minus the deep cleaning part cuz it wasn't gunked. It got a mild cam and head upgrade. These things can take a beating!
Pending confirmation of a cracked head(s), I'd be weighing my options between those refurbed NuTech heads or finding a set of 799/243s and having them refurbed (cleaned, milled, etc.). We couldn't find non-Castech 706s but found some low-mileage 799s and slapped 'em on as-is. Better flowing head, but a small loss of compression. He wasn't worried about it considering the price. In my area, I could have a set of heads done for about $300. A set of 799/243 go for $300, so it'd be the same cost invested. But, the bump in power would make it the better deal for me. You gotta reward yourself for your troubles, right?
Do the 799 heads require a different head gasket or anything else different. I can get a pretty good deal on a set of these. Will send pics shortly.
I don't see much here. One thing to note before I took this picture earlier today, there was bunch of gunk built up in between 3 and 5.
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Again I don't see anything obvious. As mentioned, my engine is super clean as you can see in the pictures. Not bragging but very clean for 200k miles. I don't see anything that jumps out at me except the lumpy stuff which I wiped off prior to these pictures. Most were in the valve cover and in between 3 and 5.
mattbta
Full Access Member
I know everyone is saying #3 or 5...but on both of mine, it was passenger side. (I know, the second time was dumb luck because I could have installed that head on DS instead.)
Not positive (and i didn't mark which cylinder on passenger it was) but think this is the crack on my OEM 163k mile set:
Not positive (and i didn't mark which cylinder on passenger it was) but think this is the crack on my OEM 163k mile set:
mattbta
Full Access Member
Yes, as seen in post 40: https://www.tahoeyukonforum.com/thr...-leak-or-head-gasket-leak.132246/post-1652668
Got it. Sorry Matt I didn't realize it was you. Alright well...Hmmm... LOL I am going to wait for Blackstone. If there is coolant found, I am going to pull the trigger on new heads, valley pan gasket, new knock sensors (one knock sensor is either broke or rust has blocked the grounding to the block and currently it is rewired to trick the system to keep going without the warning lights ), oil sensor while I am in there.
Also I was looking at your jelly pictures (LOL). It looks like driver's side had the most jelly even though passenger side had the crack in it. I think what happens is that the Jelly ends up blocking the PCV valve and hence the jelly is worse on the driver's side? Just a thought. Well if Blackstone gives me the thumbs up for coolant in the oil. Once removed, I will carefully examine the old heads and see where the crack(s) are. It will be interesting.
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iamdub
Full Access Member
Nah, stock 5.3 head gasket.
iamdub
Full Access Member
Have you looked under the passenger side cover?
iamdub
Full Access Member
NICE!Not bragging, here, either.
195K miles:
iamdub
Full Access Member
Just let quality synthetic oil do its thing!
Did you check under that passenger side cover?
