Out of ideas on overheating ready to quit

[Greg2347]

Bought a 1993 3VZ-FE V-6, body/interior in good shape for a work car, but was blowing white smoke from exhaust, clouds and clouds. Paid little for it knowing it needed head gaskets, etc. Had heads checked and pressure tested [all good] put back together with new gaskets, etc including a timing belt kit/ water pump, thermostat, etc. Got back together and would idle OK but would overheat within a mile or so of driving.

Checked and replaced both radiator caps, took thermostat back out and verified it was opening as designed, hydraulic fan working, new radiator, timing set to 10 degrees, careful to get all air from system before capping off.
And still overheating as evidenced by superhot air from the heater and water 'spitting' into overflow container. [The dash temp gauge is apparently bad as neither removing it from the sensor or grounding the wire will get the gauge to move. The fuse is good.]

So, what are we missing? Found evidence of stop leak in lower radiator hose, which was removed....it is not collapsing-remaining cold even when the top is hot and spitting into overflow container.

I am undecided as to which direction to go now......different engine......different car altogether.......

How about some suggestions. ~$750 into car at this point.

[Stillrunning]

Have you verified no exhaust gas in coolant or coolant in oil? Did you remove rad cap from cold engine and observe if there is flow as engine warms? You could also remove stat temporarily to observe coolant flow. Was stat replaced in proper position with bleed hole/jiggle valve at top to allow air venting?

[haux]

This may be a totally different overheating issue, but let me give you my check list for diagnosing an overheating problem.

First off, as long as there's no sign of a bad headgasket. You said you replaced it, but oil in coolant or coolant in oil would be a sign. I'm going to assume this is not the issue.

Second, are the radiator fans working.

Third, is the cooling system holding pressure. Both hoses should be hard to squeeze, and should not collapse. If not, this may be a problem with the radiator cap. You mentioned it was replaced. Check to make sure it hasn't fallen apart since then.

Fourth, is coolant being circulated. You already know this would either be a thermostat problem or the water pump. You said both are new. Hopefully neither of them have problems. Is the thermostat OEM or a cheap aftermarket?

I'm going to assume there are no coolant leaks.

Also, I only have experience with my 2000 i4 Camry. I'm also going to assume things are at least slightly similar between mine and your '93 v6. In my camry, there is a engine coolant temp sensor. I presume if this thing goes bad, it could cause overheating. I'm unsure how to check if it's working, but have you looked into that at all?

My Camry also has a coolant temp switch that goes to the bottom of the radiator and controls the fans. This would go to step number two.

[Frodo65]

Originally Posted by Greg2347

Bought a 1993 3VZ-FE V-6, body/interior in good shape for a work car, but was blowing white smoke from exhaust, clouds and clouds. Paid little for it knowing it needed head gaskets, etc. Had heads checked and pressure tested [all good] put back together with new gaskets, etc including a timing belt kit/ water pump, thermostat, etc. Got back together and would idle OK but would overheat within a mile or so of driving.

Checked and replaced both radiator caps, took thermostat back out and verified it was opening as designed, hydraulic fan working, new radiator, timing set to 10 degrees, careful to get all air from system before capping off.
And still overheating as evidenced by superhot air from the heater and water 'spitting' into overflow container. [The dash temp gauge is apparently bad as neither removing it from the sensor or grounding the wire will get the gauge to move. The fuse is good.]

So, what are we missing? Found evidence of stop leak in lower radiator hose, which was removed....it is not collapsing-remaining cold even when the top is hot and spitting into overflow container.

I am undecided as to which direction to go now......different engine......different car altogether.......

How about some suggestions. ~$750 into car at this point.

Well, with evidence of 'stop leak', are you sure the radiator isn't 'plugged' from corrosion and its (in-vain) attempt to 'fix' it? Is the radiator 'hot' evenly? One of the $40 Harbor Freight IR thermometers can get you that info - it can also tell you the temps on the rad hoses (how much heat is the radiator actually removing).

[Greg2347]

All good ideas, but have already combed the files and found all those diagnosis. Let me answer them pretty much step-by-step.

No oil in water, nor water in oil. No bubbles in coolant after bleeding. Not 100% sure of position of jiggle hole in aftermarker thermostat but have removed it and verified in hot water it is opening pretty much as per spec.
New radiator. Coolant is circulating after thermostat opens-hoses get hard.

The hydraulic radiator fan is working, although at the minute still has some air in the system from installing new radiator. New sensor installed in block-NO sensor in radiator, for fan or anything else.-The old one did not have one, neither does the new one. Fan operational. No evidence of coolant leaks, includes visual on ground, on motor, out tailpipe [using straight water at this time until this problem is solved] although some smoke is visable out of the tailpipe it is 'burn-off' from the prior head gasket issues and is decreasing with each run of the engine.
We [my nephew and I] are careful not to let it overheat to the point of blowing another gasket. BTW, my nephew is the resident expert on this project, having build/help build several import motors in the Jacksonville Fl. area and was a regular at the strip with his 350 powered Blazer. He is more qualified than I on this project.

This has one fan, not two. The defective sensor was replaced and verified it works.

Stop Leak....this is where I think the problem is at. Not the radiator as it is brand spanking new out of the box. I'm leaning towards a HUGE amount in the block, so much it has filled up a major part of the cooling passages. But short of total stripping down to the bare block and hot tanking it block how would you tell? Not much if any was observed behind the water pump.
Water does circulate....the cabin heater blows cold then as the engine warms up goes to hot [then burning hot as it overheats!] so I don't think one of the flush kits will do any good.

Any more ideas? Thanks for those so far.

[Greg2347]

Morning update-just checked the coolant level after sitting all night and cooling off, no water visable in the radiator. I'm sure there is some there, somewhere below the top plate. Coolant tank is sucked dry.
One suggestion was to elevate the front of the car and fill the radiator, will try that maybe today, maybe tomorrow.

Hope for a save is fading fast!!!!!!!

Did I turn a $250 junker into a $750 education?

Am I polishing a turd?

All questions that need to be answered!...and soon.

[Stillrunning]

I doubt the cooling passages are small enough to get blocked by stop leak, if that was happening I think heater core would be blocked. Sucking entire rad of coolant into engine when cool is major lack of coolant in engine and I would look to air lock when filling. Yes raise front of vehicle when filling. I'd also recheck your dipstick now to see if water in oil.

[tacosteelersman]

Confirm your heater hoses are not hooked up backwards..

[drice]

Don't give up, that's a great car and a great buy. As you know the car is sensative to PSI in the system. Even a small problem will boil it off.
You haven't mentioned the heater core, it could be your problem. They're easy to change and a pinprick leak will delflate your whole project. Put a cup of ammonia in the water and see if you can smell it at temp. If you can you know.
New radiator, the front cap needs to be replaced, don't overlook any detail. The heads don't fill completely until it has been driven but that will not cause the engine to overheat, from my experience only. Be sure you can watch the water surge from thermostat opening and closing as it circulates at the fill point on top of the engine. There are no ghosts, you will find the problem.
Good luck

[Greg2347]

Originally Posted by drice

Don't give up, that's a great car and a great buy. As you know the car is sensative to PSI in the system. Even a small problem will boil it off.
You haven't mentioned the heater core, it could be your problem. They're easy to change and a pinprick leak will delflate your whole project. Put a cup of ammonia in the water and see if you can smell it at temp. If you can you know.
New radiator, the front cap needs to be replaced, don't overlook any detail. The heads don't fill completely until it has been driven but that will not cause the engine to overheat, from my experience only. Be sure you can watch the water surge from thermostat opening and closing as it circulates at the fill point on top of the engine. There are no ghosts, you will find the problem.
Good luck

Both caps are new and appear good. Will recheck for water in the oil. Water is circulating. Good idea about the ammonia, will try that in a little while. Heater hoses hooked up backwards should not cause my problem, but they are correct in any event.

Thought....does the upper intake [that that contains the sensors/butterfly, etc.] have water passages thru it? Just wondering if there was a leak into the airstream causing a bleed off of coolant. Just grasping at straws here.

Lacking a good find today, I think the next step is to remove the upper intake and check compression/condition of rear spark plugs..starts, idles and accelerates good however.

[Greg2347]

Well, added a few cups of ammonia, started and ran until water started spitting into overflow but could not detect ammonia odor anywhere, engine, heater or tailpipe.

Last ditch straw, could it be using straight water instead of antifreeze mix cause overheating?

Upper hose hard, it and top of radiator hot, bottom hose and radiator cold.

[drice]

The casting coming out of the intake at the valley is the water bypass outlet. It has a couple of water temp vacuum switches and a coolant exit that enters the upper air intake somewhere under/around the throttle. I can' t remember where it comes back in. The pipe coming out next to it goes into the valley as you know from the rebuild and is the return. You could bypass the heater core at those two pipes and eliminate the HC as the culprit. If it acts the same you've eliminated another expensive part replacement.

[drice]

It sound like your heads are running dry if its spitting and gushing. Be careful of shock cooling them with new water when hot. Don't get scalded, I doubt you would have a problem running just water in a closed system. I hate to say this but It sounds like a head gasket leak. Go through your elimination process and be sure of each individual possible issue. Last get a co2 test done by a reliable independent.

[drice]

maybe thats a monoxide test, whatever it's the test that shows blue with burnt vapors in your coolant or water.

[Luckynumber5]

My vote is a badly clogged block from improper use of stop leak. You will need to do a major cooling system flush.


Im talking colon blow for cars, dont even bother wasting good antifreeze on it at this point, you will need to put a lot of good radiator/cooling system flush in it and take the thermostat out. Drive it a bit with the heat on high to help keep the engine cool and just flush the crap out of it a few times.

Hopefully that stop leak will dislodge and you will be able to enjoy your car, the 3vz is a great engine. Its just that they were only over here for two years so it seems like they always have problems cause the youngest factory engines are going on 18 years at this point!

Best of luck