LB7: Cooling System Headache

[Dirtymaxx03]

I am about to pull my hair out.

So i thought the truck had blown head gaskets because the low coolant light would always come on and i was always missing coolant.

Well i replaced the thermostats and i think that fixed the missing coolant problem (was spewing out of the overflow i guess) however the light will still come on.

I can be driving for 20 minutes and the truck will not heat up at all, heater wont work, truck sounds like crap. Then all the sudden the temp gauge will shoot up to 180* and the truck sounds better but the heater wont blow hot.

Eventually the heater will start working but almost at the exact same time the heater starts blowing hot, the low coolant sign will come on the DIC.

I can stop the truck and turn it off and check the coolant and it will look real low, as soon as i pop the cap and relieve pressure, the coolant level will rise to where its supposed to be.

Its like the cooling system is over pressurizing itself or something.

HELP

 

[DIESELMAFIAPER.LB7]

I am about to pull my hair out.

So i thought the truck had blown head gaskets because the low coolant light would always come on and i was always missing coolant.

Well i replaced the thermostats and i think that fixed the missing coolant problem (was spewing out of the overflow i guess) however the light will still come on.

I can be driving for 20 minutes and the truck will not heat up at all, heater wont work, truck sounds like crap. Then all the sudden the temp gauge will shoot up to 180* and the truck sounds better but the heater wont blow hot.

Eventually the heater will start working but almost at the exact same time the heater starts blowing hot, the low coolant sign will come on the DIC.

I can stop the truck and turn it off and check the coolant and it will look real low, as soon as i pop the cap and relieve pressure, the coolant level will rise to where its supposed to be.

Its like the cooling system is over pressurizing itself or something.

HELP

gasket...... mine did the same thing when it went

 

[Dirtymaxx03]

gasket...... mine did the same thing when it went

well if the gasket took a shit, i figure i would be using coolant. But im not and thats what has me stumped. Im not keeping this truck much longer so if i tear into it to fix the gaskets and install studs, only to find it didnt need it, i'll be pissed

 

[MACKIN]

Sounds like head gasket

System is pressurizing pushing coolant or not allowing it to flow correctly that's why you're seeing the spike in temperature then all of a sudden heat. You said that it was pushing coolant out of the overflow which means it is pressurizing so you must be loosing coolant.

 

[Dirtymaxx03]

Sounds like head gasket

System is pressurizing pushing coolant or not allowing it to flow correctly that's why you're seeing the spike in temperature then all of a sudden heat. You said that it was pushing coolant out of the overflow which means it is pressurizing so you must be loosing coolant.

It was pushing coolant out before the thermostat change. I could fill my truck up with coolant, dry off the area under the overflow spout, go for a hard drive and see where coolant had shot out of the overflow. Stopped doing that after thermostats changed.

i feel like if the headgaskets were blown, a 3100uS tune at 30* of timing would drain the coolant in a short time under WOT, but it doesnt

 

[DIESELMAFIAPER.LB7]

Mine doesn't puke much with 2700 Pw on 45 overs 66 and dual pumps and lots of 1/4 mile passes just sucks the coolant down till I relieve pressure then it pukes and comes up to a more normal level

 

[DIESELMAFIAPER.LB7]

Sell it and say it needs a gasket if you don't want to do it

 

[Dirtymaxx03]

How long have some of y'all ran around with blown head gaskets?

 

[DIESELMAFIAPER.LB7]

How long have some of y'all ran around with blown head gaskets?

Year and half

 

[2001-GMC-LB7]

My 2001 ended up being injector cups (2) leaking, installed new head gaskets and rebuilt heads to fix it... You Know I also HAD to install ARP studs, rebuilt injectors, injector lines, Glow plugs, new water pump, new turbo (Bigger), bigger down pipe, rebuilt injection pump, all hoses, and pulleys, tensioner, belt, while I was at it...

 

[Dirtymaxx03]

Yeah I'm kinda stuck at a fork in the road here.

I could go drop 15-20k on top of what I sell this truck for and get a nice new stock truck that's quite and reliable.

Or

I drop some money into this truck
Carrilos
Cast ovals
Head and main studs
Key way work, etc
Nothing big. Hell I might just slap a set of rods in it and call it a day.

Who knows. All I know is I have lost feelings for my truck. She's not the same. It might be time we broke up lol

 

[DIESELMAFIAPER.LB7]

Yeah I'm kinda stuck at a fork in the road here.

I could go drop 15-20k on top of what I sell this truck for and get a nice new stock truck that's quite and reliable.

Or

I drop some money into this truck
Carrilos
Cast ovals
Head and main studs
Key way work, etc
Nothing big. Hell I might just slap a set of rods in it and call it a day.

Who knows. All I know is I have lost feelings for my truck. She's not the same. It might be time we broke up lol

Lml time