93 camry v6 no heat (again)

[brian long]

Good morning, I know we are all busy, so i'll try not to ramble. just looking for a little direction.

This all happened in the last 3 weeks!

bought it used with 121,000 miles. It had a new radiator and clean green coolant. Had terrible heat.

leaking water pump, paid the local Toyota garage to replaced the thermostat, water pump and timing belt. They used red coolant.

Had terrible heat. (80 degrees discharge even with the engine temp guage needle running just below horizontal) I let it go, as I was dealing with several other things that needed fixed first. It didnt leak anywhere.

Once I noticed when i revved the engine in park that it made a gurgling sound near the heater core. I bled the cooling system thru the upper cap, and I now had 120 degrees discharge temp! Thought I had it.

I had several days of great heat, but last nite when accelerating from a stop with a warm engine, I heard that gurgling sound again, and now i'm back to 80 degrees. tried bleeding again. no luck. (It was 30 degrees outside)

I know some may say plugged heater core, but I really don't think so. Also checked the heater valve, and I absolutely hadn't moved the dash control or valve last nite when I lost the heat.

Both heater core hoses are hot with the fan off, the discharge hose is much cooler with the fan on high speed.

Thank you, any ideas would be GREATLY appreciated.

[chronoti]

collapsed hose, replace the hoses they are prolly worn and are collapsing under the load causing a restriction

[brian long]

Thank you. I'll try that. Any hose in particular that you know is a problem?

I assume it would be the heater hoses going to the valve, not the radiator hoses.

[BlueFusion6851]

Check 'em all, but are you sure your coolant level isn't low?

[brian long]

After the new pump/t-stat i was able to bleed it by 'carefully' cracking the cap loose when it was hot and running. I would get air and coolant. (I was only losing about 1 ounce of coolant) I always topped off the jug. this procedure really helped the poor heat. (or so I thought)

Last nite when I lost heat I tried it again. I actually was able to remove the cap while it was hot and running. for some reason it had very little pressure.

It has no coolant leaks. I park it in a garage and check the floor every morning. nothing. the jug is full.

I would assume since the Toyota garage did the waterpump/t-stat that they used the correct, high quality parts.

With the problem i'm having, i always park it where if it boils over i would see it on the blacktop. nothing

I would think the hot to cold control is the water valve, and the doors are simply air direction, so it's not worth looking at door operation.

PS: after I (thought) had the heat fixed, I purposely did not touch the control knob on the dash. still haven't moved it from full hot.

Thank you in advance for your time

[73sport]

The gurgle sound typically only happens when air is in the system.

Although it may not have a visible leak, I'd replace the radiator cap, as it could be sucking air in every time you turn it off and/or it cools down. When the air gets in, it circulates to the heater core and gets trapped in the core. Hence there it no heat being exchanged.

Also look closely at the sealing surface where the radiator cap fits. There are two lands which must be flat for sealing. Confirm these are in good shape and ARE not cracked anywhere.

Go with the radiator cap. It explains a good deal WHY this happens.

PS - my 95 V6 has an air bleed fairly high up in the cooling system. Perhaps by the thermostat?? This might be helpful if your's has one too.

[brian long]

sounds reasonable. And easier/cheaper than just about every other idea I have!

please tell me if I should also replace the cap on the housing where the top hose connects to the intake. As I recall they look the same?

thank you

[73sport]

Originally Posted by brian long

please tell me if I should also replace the cap on the housing where the top hose connects to the intake. As I recall they look the same?

So your saying it has two caps? But only one connects to the radiator over flow? Replace the one connected to the overflow tank. But doing both would be best.

If it has a purge vent on the intake, you can use it to bleed some of the air after cooling.

In my opinon, I find it less likely that the heater hoses are collapsing, UNLESS the system does not build pressure.

Tell me this: after you drive it for 15min, does the top radiator hose get hard or can you squish it easilly with your fingers? How long can you keep your hand on it? It should be about 170 to 190 degrees and under pressure. You stated it doesn't boil over, are the cooling fans on ALL the time? It should be hot.

Let us know. . .

[brian long]

Sorry, I meant that the caps look the same.

Answers to your questions:
1. I see no purge vent.
2. Seems like sometimes the top hose is firm and other times not. I'll check it again.
3. Top hose is always hot after 15 minutes running. (the temp guage needle comes up quickly and stays steady at just below horizontal)
4. It has the hydraulic fan, runs (slowly) all the time. It's been below freezing since i bought the car, so have no idea what it'll do when the weather warms up.

If the engine heats up quickly and stays hot even tho it throws no heat, I would say the fan operation isn't a problem right now ??

The second cap I mentioned is on the 'water outlet housing' Gates lists both caps, with different p/n's. Local parts store carries both. I may just replace them.


cheap easy guess

Thank you for your time

[brian long]

Good morning, I am responding to what 73sport asked me to check.

-After 15 minutes, top hose is hard and hot.
-I can bleed off a small amount of pressure/fluid, then remove the cap every time.
-Temp guage needle comes up quickly to just below horizontal, and stays there.
-Never boils over.
-Nothing leaking
-The hydraulic cooling fan runs constantly, but I can easily stop the blade by touching it. I just bought the car, so I have no idea what it will do next summer.

I replaced the cap on the radiator and the cap on the water outlet. After bleeding it several times I now have 115 degrees coming out of the dash vent.
I'm satisfied, but will reserve saying it's fixed till i drive if for awhile. (i thought it was fixed the last time i bled it multiple times!)

I have a question. I probably drove it 2 miles and then bled it at least 10 times. each time I seemed to get a hotter dash vent temp. does it sound normal to have to bleed it that many times?

Here's the kicker. I see a constant flow of tiny bubbles looking into the water outlet with the cap off. very tiny bubbles, like what you would see rising to the top of a glass of beer.

Do I have a blown head gasket? Thank you

[BlueFusion6851]

The hydraulic fan will always be running a little bit from what I remember, so that's not a concern.

What concerns me is that last part you say. I remember mine doing the same thing and I ended up having a VERY TINY headgasket leak. My car would only overheat when I would drive from Minneapolis to St. Cloud.

[73sport]

Sorry, you lost me at the beer analogy. . .

The system flows from top to bottom so looking into it with no pressure, it could easly have bubbles. If the system holds pressure, those small bubbles will disapear. Well unless the head gasket is defunct.

Here is the next important question: Does the reservoir volume move up and down through heating & cooling cycles?

In use, the coolant expands as the engine warms. Some of the coolant gets dumped into the resevoir when it expands. When the engine cools off, the coolant contracts, the check valve in the rad cap opens and allows the coolant to be pulled back into the block so the reservoir volume drops when the engine is cold.

Does it do this? If it doesn't, it has a leak somewhere. Do a pressure test of the cooling system. Oh, check the oil and tell us it looks like oil. Open oil fill cap and look for white milk. Thats the sign oil is mixing with water. Soemthing you don't want to see.

[fenixus]

just a quick thought, maybe it was posted already, if yes then sorry (i'm half asleep), but have the OP replaced the radiator cap with new one ? this air must be getting into system from somewhere.

[brian long]

Good morning, responding to the last two posts. Thank you all for your input and help.

Radiator cap and water outlet housing cap are new (Stant brand from NAPA)

Coolant in reservoir rises 3/8" and goes back to original level. This is during/after a 15 minute drive.

Oil on dipstick is not milky.

No crud under the oil fill cap.

I see nothing on the garage floor after the car sits overnight.

I'll drive it for a week and see if I still have heat. Thanks again

[kei_kusanagi]

OMG!!!: LOL :P

http://minneapolis.craigslist.org/ra...613894109.html