05 Suburban, intermittent heat

[dan filipi]

Ideas guys?

It has intermittent heat which oddly comes on more heat when turning a corner (?) but still not full hot.

We had front end repair which lost all coolant from the accident, I assumed they filled the system completely and appeared so after the repair in the reservoir but this reservoir is kinda funky, it has "cells" inside which have coolant in them.. After looking closely inside I can see the "main" part of the reservoir is empty. Doh!

The heater hoses feel barely warm.
I'm going to fill up the system, hopefully it stays that way.

My question is with no external leaks are we looking at a possible blown head gasket?
It has rear heat so I've instructed the wifey to keep a close look out for any coolant showing up anywhere inside or out and underneath.

Is there a way to test for coolant in the exhaust gas?

 

[slabghost]

Probably air in the system. Newer cooling systems are closed up tight and need "burped" to fill completely.

 

[dan filipi]

Good point, maybe repair guys never burped it.
Crossing our fingers its that simple.

It took almost a gallon and heat is working good.
Noticed too the coolant temp is lower than its been normally for a long time.

BTW, happy birthday Vince!

 

[slabghost]

Dealer should know better but everyone makes mistakes.
Thanks!

 

[scdmarx]

Assuming it was full to begin with, if the coolant is low there has to be a leak somewhere. It could be losing steam under pressure. Maybe a little at a time over a long period. This could be happening at the radiator cap, any of several hose clamps, water pump seal or weep hole, intake or thermostat gasket, the seams at the radiator tanks, etc. Look for stains or corrosion around these areas. This can also be the result of too much pressure. The system is designed to operate within a desired pressure range. So if the fan clutch is kaput, or blockage of air flow through the radiator core, or something like that, the pressure will rise with added heat and start seeping out at whatever weak point it can find. Heater core leaks will piss on the carpet and blow steam on the windshield. As for the head gaskets....sometimes it's obvious, sometimes not so obvious until it gets worse. The sooner you can catch it, the better. This may be difficult without the use of a pump to pressurize the cooling system. For the tricky ones, I have in the past had to leave it pressured up overnight to prove it the next morning. You can look for little tell-tale signs like coolant bottle likes to overflow often, or if you can tell there is a misfire or roughness in running when you first start the cold motor in the morning and then it smooths out and runs fine. As for the temp gauge not going high enough, I'd tend to think this may be due to the low coolant level. The sensor only works when it touches water. Low coolant level will increase air cavitation. If you can't see anything obvious, then $7-$10 for a new radiator cap won't break you. (or have the one you got tested?)

 

[dan filipi]

Thanks, I'll get a new cap.

I don't see anything at any of the points you mentioned, I've had a heater core leak in the past so I know how strange that presents itself but wifey doesn't.
I thought for an instant I could smell antifreeze inside when I ran out for a haircut but could be my imagination.

When I got home it had completely warmed up from the run. The reservoir is down a tiny bit so I'm going to let it cool a few hours then mark the level on it with a sharpie for a cold level reference.

I instructed my wife to keep a close eye on the ground where she parks like at the grocery store and other places and look for any spots before pulling in then look again when she pulls out.
Sure hoping for an external leak, I'll take the heater core as an option. Not easy but a lot cheaper than blown head seal or worse.

 

[toytender01]

A couple things you can check : Look for air bubbles in radiator, Put your hand over the exhoust and if it shows moisture no your hand. You may be able to go to the "ZONE" and rent a radiator tester which will presurize the radiator or the cap. I have 2 of those testers here, 1 mine and 1 belongs to a Mech who has his tools stored with me, so I am gifted. I also have a unit you fill with water and stick it in the top of the radiator and it helps detect bubbles. :Egyptian: :Egyptian:
:mrgreen: Now if I just knew what it all means. :smilie_happy: :smilie_happy: :smilie_happy:

 

[Tory]

Dan,you didnt say what year burb it is.
The older 5,7 variations from 96 up untell the 5.3 came out have a notorious problem with intake gaskets.I feed my family with this type engineering flaw.
Either way,seeing it has just had service I would not stress it untell it is low again.The burbs have a large cooling capacity especially if it has rear heat and its not unusual to have to top it off after a few heat cycles.Remember the heater core is the highest part of the system.

What are you using heat in california anyway.

********EDIT****************
Sorry,I see you have the year in the heading.
I still sell a few intake sets for the 5.3 but not quit as common.Just remember car parts are not like our bike parts,aftermarket supliers have found problem spots in parts such as GMs plastic intake gaskets and improved them like felpros steel laminate design.
If you get the testere be shore to get the adapter to test the cap also.

 

[dan filipi]

Hmm, question,

The reservoir level has dropped about an inch while cooling.
I understand this can be normal as coolant gets drawn back into the engine?

Also the owners manual says if having to add coolant more than 4 times a year to maintain a "cold" level then consult a mechanic.
I added about 3 quarts and haven't added any since we had the front end repair about 1-1/2 years ago.
Could this be a "normal" loss in coolant?

Seems odd from my experience, any loss is bad but these newer systems are a whole new breed to me.

 

[slabghost]

could be normal to get an air bubble too if the reservoir is allowed to empty. it would draw air in.

 

[dan filipi]

Found the leak. It's where the pump bolts to the block.
I gave the bolts a crank, got a 1/2 turn on them all hopefully that'll stop it. If not I'll be doing car mechanical stuff this weekend.

 

[scdmarx]

Found the leak. It's where the pump bolts to the block.
I gave the bolts a crank, got a 1/2 turn on them all hopefully that'll stop it. If not I'll be doing car mechanical stuff this weekend.

Good deal! I'll keep my fingers crossed for ya. :yahoo:

 

[dan filipi]

Well it looks like giving the 6 bolts a crank down did the trick! :yahoo:
Not a drop there in a few days and the wife and kids sure appreciate the heater working now.

In celebration I bought her (the burb) both new belts.
My luck those won't be easy but easier and $100 less than replacing the pump!

The parts store said he sold 2 of these pumps yesterday.
We were joking maybe this is all that's wrong with them :smilie_happy:

 

[slabghost]

good deal!

 

[scdmarx]

That's great news.

The parts store said he sold 2 of these pumps yesterday.
We were joking maybe this is all that's wrong with them :smilie_happy:

You gotta understand the scenerio here. If you took it to a shop and they discovered that those bolts just needed some retightening, and you left all happy and jazzed, then your wife drove the car, and it overheated, (for any reason, but let's say it was the water pump just for luck) but not in a safe or convenient place to stop, and the motor scorched before she stopped....or the fan went through the radiator - take your pick.

"who ya gonna get mad at?" You just paid money to have it checked out, and it was discovered the water pump was leaking, some goofball cranked the bolts down and called it good, but now your motor is burned up from coolant loss. Now you'll demand something be done about it. In your mind somebody owes you a new motor, a rental car, and a motel room. This is what the plaintiff will sue for. Warranty for a part the defendant never sold him. This is not far fetched. It happens. No good deed goes unpunished. Intelligent mechanics know, if there's a leak @ that water pump, it gets a new one that can be warrantied or they ain't touch'n it. Does anybody know how many miles are on that water pump? The parts store guy may have sold 2 of them due to the gaskets leaking, but they'll come with a warranty because who ever put a wrench on it last owns it.

Your wife doesn't want a new water pump. She may not even be interested in what a water pump does. What she wants is a car that will start at 2 am in a dark parking lot and transport her dependably and safely to where she wants to be. Oh, and with heat. :yes:

PS: I understand it was a joke, and I got it. :smilie_happy: :salute:
I didn't sleep last night and unexpectedly started a new job today and I'm kinda burnt. :lazy:

 

[mcgovern61]

That's great news. - PS: I understand it was a joke, and I got it. :smilie_happy: :salute:
I didn't sleep last night and unexpectedly started a new job today and I'm kinda burnt. :lazy:

Hey Ron...Good luck on the new job!!! :clapping: :clapping:

 

[scdmarx]

Hey Ron...Good luck on the new job!!! :clapping: :clapping:

Thursday I was out of work by 10am. With the schedule looking similar for Friday, we mutually agreed that I should just take off. I had already given them notice on Monday. I was all set up to have help and a trailer available to move my tools to the new job on Saturday. So Thursday at 10am I left and took my smog license over to the new job to have my I.D. put into their machine so I'd be ready to roll come Monday. The lady makes a phone call to the state office, performed a DATA refresh on the smog machine, and asked me if I wanted to work. So Thursday about 11am I started working and by 5pm I had made $138 (take home) commission with no tools, and not knowing any shop procedures or where anything is. Friday I showed up at 8am and made way over $200 by 5pm under the same conditions. No tools, very disoriented and very busy.
This shop runs the way we used to do things back in the dark ages. It used to be a 2 bay gas station way back when and is very cramped with 2 mechanics with massive tool boxes, but hey, they're busy and I'm working. :whip:

I've been kinda spoiled driving 5 miles to work in 7 minutes for the past 6 + years. This new job is 23 miles and takes a good 35 minutes to get there. I hope I can adjust to having work to do and keep up with their pace.

 

[dan filipi]

Good to hear!
Imagine when you have your own tools and settled in.

 

[scdmarx]

If it keeps getting better, I'll have a new front tire in no time! :yahoo:

 

[dan filipi]

I been thinkin ( dangerous thing to do sometimes) Ive read these engines develop a intake leak.
Wise to give those bolts a maintenance crank or wiser to leave well enough alone?