Engine long warm up/half way warm up

[BaMaDuDe87]

Water pump - new
Thermostat - new (Didn't do the put in water trick to test it though. Came from stealership. Third one so far)
Fan clutch - new (actually off for the past few days too see if it seemed to make a difference. Nope.)

What am I missing? I'm thinking an overheating engine would be easier to diagnose at this point. "Burped" the system about 5 times now. Got a cooling system pressure tester coming, block tester to check for combustion leak and a compression tester. Guess drop another $35 for a new thermostat again and test it before putting it in this time? Can it really be hard to make and test thermostats before selling them?

Sent from my SM-N910V using Tapatalk

 

[bottomline2000]

From a cold start the lower radiator hose should be cold. If it gets hot immediately you have a bad thermostat. If it works correctly it will take awhile for it to open and let hot coolant thru.

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[bottomline2000]

If you are just letting the truck idle in cool weather it will take a while to warm up. We got almost 3ft of radiator!

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[BaMaDuDe87]

If you are just letting the truck idle in cool weather it will take a while to warm up. We got almost 3ft of radiator!

Sent from my SAMSUNG-SM-G900A using Tapatalk

I'm in Alabama, it doesn't get that cold down here. For example though, I let the Tahoe warm up for about 5 min this morning (is was around 55 outside), then drove to work about 15 min and it was just creeping past 185'ish. I guess 86°C (whats on the thermostat) actually comes out to 186.8°F though.

From a cold start the lower radiator hose should be cold. If it gets hot immediately you have a bad thermostat. If it works correctly it will take awhile for it to open and let hot coolant thru.

Sent from my SAMSUNG-SM-G900A using Tapatalk

For some reason I was thinking it was the top hose. Will check in the morning.

Sent from my SM-N910V using Tapatalk

 

[bottomline2000]

I think what u are experiencing is normal but check it out and see if the thermostat is working.

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[BaMaDuDe87]

Well seems the thermostat is doing its job. Drove it today and stopped when the temp got around 185 (about 10 min from start, 5 not driving and 5 driving) and the lower hose was still cold. Just seems weird it's taking soon long to warm up. New rad and new thermostat cause this damn thing to be too efficient. Still waiting on the new toys to test the rest of the engine.

Sent from my SM-N910V using Tapatalk

 

[BaMaDuDe87]

Well it's been acting kind of fine....until today. Still wouldn't get past 185 on the way to work in the mornings, but afternoon commutes home went fine.

Drove hard for 30 min home from work. Dash temp stays a touch below 185, lower hose still cool to touch (basically same as outside air). Fan/fan clutch still off engine. Will check coolant level again in the morning. Super lost.

Sent from my SM-N910V using Tapatalk

 

[BaMaDuDe87]

Test #1 - Negative for blown head gaskets. Used an OEMTOOLS block tester and lisle test fluid.

Also got it to over heat tonight. Odd that I'm happy about that, but this is the first time in about a month I've managed to make that happen.

Sent from my SM-N910V using Tapatalk

 

[BaMaDuDe87]

Static pressure test with Mityvac MV4560 - 20+min - Pass (No drop at all that I could tell)

Cap pressure test - Pass

Dynamic pressure test @ 60°F outside temp - Ongoing - Took 16 min to reach "operating temp" High 190s. Coolant system pressure is about 5 psi at this point. Is she having trouble making pressure on her own? I would think the "operating" pressure would be around 15psi?

@30 min - Temp is 204.8 and pressure is 8 psi.

Sent from my SM-N910V using Tapatalk

 

[06 Yukon XL]

Why are you idling your engine before driving. Even when it is -15C I get turn on the engine drive off. Modern engine just don't need to warm up before driving. Also this way you warm your engine and transmission at the same time.