Wife calls me and says her tahoe has no heat. while on the phone she saysthe temp gauge is on the cool side.
I order a delco thermostat, swap it out tonight, burp the cooling system.
Go for a drive, at a red light notice the heat coming out the vent is lukewarm, take off from the lights, engine above 2000 rpm, heat out the vents is hot, get to cruise speed, convertor locks up, heat out the vents cool off, kick it to passing gear, temp goes up coming out the vent.
Back in my driveway, idling both heater hoses are warm, (not hot), give it rpm, both hoses get hot,
would i be wrong thinking the waterpump is the culprit?
Being rpm related is why i am leaning this way.
Thermostat is an hour old
Radiator is 6 months old
Coolant level is right up
2000 tahoe
5.3
Any thoughts are welcome folks. (i am sleep deprived to much overtime, not trusting my own judgement)
A Friend changed EVERYTHING on his to fix this issue along with other things so the one thing that wasn't changed was the Coolant tank CAP.so I did and it fixed it. it looked ok but would release pressure and water along with not heating up(you'd think otherwise)
Coolant cap is a maintenance item that is regularly forgotten. On 7.3 diesels it can cause serious issues.
A bad cap won't keep it from warming up, it will just make it boil over when it does get hot. I'd guess that the fins are rusted off the pump impeller, or maybe the heater core is plugged up.
Sounds like a circulation issue, id start at water pump.
BrokenYugo wrote:
A bad cap won't keep it from warming up, it will just make it boil over when it does get hot. I'd guess that the fins are rusted off the pump impeller, or maybe the heater core is plugged up.
Bad cap could prevent an air bubble from being purged properly, and that could cause heat issues or other oddities.
Take the heater hoses off the engine, hit the core with the garden hose, then fill it with clr for an hour. Flush the core again. Refill, bleed and enjoy heat. 99 times out of 100, lousy heat at low rpm is a restricted heater core.
Easy to try before you change a water pump on an engine that has a pretty bulletproof pump.
thanks folks,
I'll go back at it tonight, when i get off work
rslifkin wrote:
BrokenYugo wrote:
A bad cap won't keep it from warming up, it will just make it boil over when it does get hot. I'd guess that the fins are rusted off the pump impeller, or maybe the heater core is plugged up.
Bad cap could prevent an air bubble from being purged properly, and that could cause heat issues or other oddities.
Couldn't have expressed that better.
Rear heat? That needs to be bled too...
I think you've got leak somewhere (possibly internal to the engine) and air in the system. I doubt that the t-stat was bad in the first place.
APEowner wrote:
I think you've got leak somewhere (possibly internal to the engine) and air in the system. I doubt that the t-stat was bad in the first place.
If this is the issue a coolant system pressure test will diagnose this.
If you don't have the kit to test the cooling system I think they are a free loaner tool at most parts stores.
yeah, I'm a moron.
Couldnt sleep, ran it up to temp this morning, shut it off, made a coffee, popped the recovery tank cap, there was no pressure.
Facepalm, swapped recovery caps, and had heat.
Thanks folks, I truly appreciate the help!
warpedredneck wrote:
yeah, I'm a moron.
Couldnt sleep, ran it up to temp this morning, shut it off, made a coffee, popped the recovery tank cap, there was no pressure.
Facepalm, swapped recovery caps, and had heat.
Thanks folks, I truly appreciate the help!
Excellent! I'm glad you got it sorted and that it was such an easy fix in the end.
