Let me pick your brain! Haha

[C.bowles2]

So my lly slowly started spiting a bit of coolant out of the over flow hose on the reservoir. Then i had it parked yesterday and it was really coming out the overflow. So naturally i try to release the cap very slowly to release some pressure haha then boom coolant everywhere. Engine wasn't too hot. Like 130-150 degrees. Coolant wasn't hot on my hand. So i thought oh great time for head studs and gaskets and a lot of money. Well i started diagnosing it and first i pressurized the system and pulled the glow plugs. Nothing came out while pressurized for an hour, then i cranked the engine over and still no coolant came out. So i reinstalled glow plugs and drained the coolant system then i brought the system down to a vacuum. 25 inches to be exact i think. I cranked the engine over again and the vacuum held while cranking. And held for about an hour after. What do you guys think? Thermostat? Also while driving hime last night the temp read 87 for like 8 minutes of driving then shot uo to 130. Any ideas? This is where its at now tore down cause i thought id be doing head gaskets.

05 Chevy LLY
-Extended cab short bed 4x4
-Sinister EGR delete kit
-S&B turbo mouth piece
-Sinister intake tube
-AEM CAI
-PVC reroute
-4inch straight pipe
-Edge CTS juice with attitude plus hot tuning
-PPE race plug and ported FR fitting
-33's

Sent from my iPhone using Tapatalk

 

[Yngdmax92]

that is extremely weird, just to make sure why dont you do a bottle test to make sure that your gaskets arent leaking. Its alot easier to tell from what i have learned in my past experiences

 

[Yngdmax92]

while your at it, prove or disprove that the thermaostats are working. Take a heat gun and put it some where on the engine block and keep jumping back and forth between the engine and the radiator. You should be able to see if the thermostats open or not from seeing the temperature suddenly rise on the radiator

 

[C.bowles2]

Whats a bottle test?


05 Chevy LLY
-Extended cab short bed 4x4
-Sinister EGR delete kit
-S&B turbo mouth piece
-Sinister intake tube
-AEM CAI
-PVC reroute
-4inch straight pipe
-Edge CTS juice with attitude plus hot tuning
-PPE race plug and ported FR fitting
-33's

Sent from my iPhone using Tapatalk

 

[darkone98]

Yours is doing exactly what mine did with bad head gaskets, both the temperature and the leaking. My leak was minor enough that it wouldn't show on a leak-down test, but with the engine running it had enough compression to push combustion gasses into the cooling system and cause it to puke out of the overflow. LLY's are famous for it.

 

[C.bowles2]

Hmmm, but i mean with the cooling system being pulled to vacuum and the engine being cranked over you would think it should show. All cylinders are 300 psi


05 Chevy LLY
-Extended cab short bed 4x4
-Sinister EGR delete kit
-S&B turbo mouth piece
-Sinister intake tube
-AEM CAI
-PVC reroute
-4inch straight pipe
-Edge CTS juice with attitude plus hot tuning
-PPE race plug and ported FR fitting
-33's

Sent from my iPhone using Tapatalk

 

[onebaddmaxxx]

Easy. put it back together to start it, leave the cap off the thermostat cover. fill it back with water and start it. look for air bubbles come up. Will likely be small bubbles at idle. Which ever side the bubbles come up from, is your bad headgasket. Its fail proof

 

[C.bowles2]

Easy. put it back together to start it, leave the cap off the thermostat cover. fill it back with water and start it. look for air bubbles come up. Will likely be small bubbles at idle. Which ever side the bubbles come up from, is your bad headgasket. Its fail proof

So if im catching your drift, start it without the while thermostat cover? Im not sure what you meant by cap.




Sent from my iPhone using Tapatalk

 

[C.bowles2]

Any other ideas guys? At a stand still with this




Sent from my iPhone using Tapatalk

 

[Big Block 88]

Your thermostat cover has a bleed screw on it. Put it back together without the thermostats and start it pull the bleed screw with a full cooling system. It may bubble in the beginning for air that got trapped but then it should stop. If it is blowing coolant mist out while running its really blown. If it is just bubbling then its still bad. Typically if you have bubbles in your overflow ur screwed man

 

[chevyman98]

Use a combustion tester auto parts stores rent them just buy the fluid if it turns green then you have head/head gasket problems

 

[C.bowles2]

Ok thanks guys, a diesel will change the tester green? I did that test and it stayed blue..




Sent from my iPhone using Tapatalk

 

[darkone98]

It should turn green then yellow if it detects combustion gasses. Did you pull vacuum through the top of the tester and do it at operating temperature? Also is your overflow tank darkening?

 

[onebaddmaxxx]

Yes start it WITHOUT the thermostat cover on it.

At idle i doubt it would bubble enough to push thru the bleeder screw at your not making any boost, hence while i take the thermostat cover off to see the little bubbles

 

[chevyman98]

Diesels combustion normally turns green depending on who makes it. Truck should be up to operating temperature to test it. With or without tstats should work.