Coolant vanishing
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
Coolant vanishing
I drove my car about a couple of weeks ago for a short while. I always pop the hood and give it a once over before shutting it down. A few days later, I noticed coolant puddling on the floor on the passenger side. i removed my blower so that I could get a better look at the thermostat housing. It seemed dry. I found that on the driver's side, the coolant had vanished from the reservoir and was empty. I found traces of old coolant (white) streaks near the overflow tube as if it had dripped down from there and on the front of my black Mezeire water pump. I remove the cap, and hear the whooshing sound of air rushing in to the reservoir. I filled it back up and ran the electric pump to prime the system. I found no leaks after doing this. 4 days later, I find a puddle under the driver side. I pop the hood and see coolant slowly dripping out of the overflow tube coming from the reservoir. I begin to remove the cap, and coolant forcefully shoots out of the overflow tube as if it is under immense vacuum. I close the cap and it stopped. I am capable of my own repairs, but I am not sure what is causing this and would like some guidance here.
Safety Car
Joined: May 2006
Posts: 3,696
Likes: 492
From: Potomac MD
So basically is it totally cold when you are popping the radiator cap and hissing coming out of over flow? If totally cold I could see it being a head gasket as it is only suppose to hiss when it is hot when it is cold then it should open with no pressure. The head gasket is creating additional pressure even when cold.
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
So basically is it totally cold when you are popping the radiator cap and hissing coming out of over flow? If totally cold I could see it being a head gasket as it is only suppose to hiss when it is hot when it is cold then it should open with no pressure. The head gasket is creating additional pressure even when cold.
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
Coming from somewhere on the front of the water pump. I cant remember if I used thread sealant last time. Do these bolts go into a water jacket?
Safety Car
Joined: May 2006
Posts: 3,696
Likes: 492
From: Potomac MD
I think they might go into the water jacket, if not maybe one does. Do a paper clip test and see where it goes of if you have a mirror. Though this would not explain the big hissing sound out of tank on a cold motor. For simple leaks also check your front steam crossover tube and the temp sensor tightness on the passenger side in front of the number 1 plug.
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
I think they might go into the water jacket, if not maybe one does. Do a paper clip test and see where it goes of if you have a mirror. Though this would not explain the big hissing sound out of tank on a cold motor. For simple leaks also check your front steam crossover tube and the temp sensor tightness on the passenger side in front of the number 1 plug.
I have a steam vent w AN fittings and confirmed they were all good. And the ECT is on the driver side and is in there nice and tight.
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Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
Pulled the passenger head and found the culprit..
Found some light rusting on one of the cylinder walls. I also found that all but one of the header ports are white from coolant. The ls9 gasket had no signs compromise, perhaps the head warped...
Found some light rusting on one of the cylinder walls. I also found that all but one of the header ports are white from coolant. The ls9 gasket had no signs compromise, perhaps the head warped...
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
I couldn't find any cracks in the sleeve. Those are steel and I'd probably be more likely to find some crack between the valves. Ill take the heads in to get resurfaced, checked and cleaned.
Safety Car
Joined: May 2006
Posts: 3,696
Likes: 492
From: Potomac MD
Good at least you check the sleeves its still an OEM sleeve but not as thin as the LS7 sleeve which is prone to split in forced induction scenarios. Were any head bolts/studs looser than normal when you took apart. Hope you find the leak.
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
I found that the studs on the intake side of the head weren't very tight. All of the other studs were very tight. I have to check ARPs specs for all the studs as this may be by design.
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
I removed the other head today and everything looked normal on the driver's side. I'm thinking of switching to trickflow genx 255 heads. I'd like a head that can support 1000whp. I'm at 890 now on pump gas. Anyone have experience with these heads?
Thread Starter
Burning Brakes
Joined: Feb 2013
Posts: 1,021
Likes: 52
From: Coral Springs, FL
I had the heads checked. No issues there. I went ahead and purchased the TF 255 GenX heads. Unfortunately, my Yella Terra rockers won't work with these heads. So, I will need new rockers as well.
I will post more pics this weekend during the install.
I will post more pics this weekend during the install.
Last edited by slow goat; May 7, 2020 at 11:05 AM.
