HELP Car Overheated Today

[Felix_29]

Hi, I was on my way to meet my ODOC club today when I noticed about 10 minutes from home my engine temperature gauge was running hotter than usual. I usually check this often while driving. I ended up turning around to get home and I noticed the guage kept getting hotter and hotter. When I was almost home I lost the A/C and I got it back into the garage where smoke was coming from the general area of the stainless tank area. I am also noticing some green droppings of fluid on the floor as well from that area. What do I do now? It smelled awful. The engine temperature guage was going above 126. I hope I didn't damage anything permanetely while driving this this only a short while.

[Ozzie]

You may have a small leak that has been depleting your coolant. Once it goes low enough, it can start introducing air into the system, and an overheating situation is not too far then. That's one way it could have happened. Others may be the cooling fans never turned on (either electrical issue or fan issue), bad thermostat, sensors, belt related (tension/slip), etc.

The smoke you saw was coolant boiling. The The coolant you saw on the floor was the overflow.

After the car has cooled off, you can refill coolant, run the car at idle, and bleed off the air. Keep a watch on the temperature gauge, and it should stabilize, as well as the fans should kick in. It the temps keep going up, shut the engine down.

You should also get a coolant pressure tester ($70 at Harbor Freight) or rent one for free at Autozone. Your system should be able to hold 15psi for at least 30 minutes, if it doesn't you have a leak somewhere. Best case is loose clamps, worst case is ..well, correctable but could add up.

[sdg3205]

Where did you see coolant dripping from?

I had the same experience once, though I caught it early (before the 220 F mark which is obviously too much for spring in vancouver).

I had a clamp work its way loose off the water pump on the driver's side.

Do as Ozzie suggested. If it ever happens again, pull over, let it cool and check your fluid level. Worst case is you buy some bottled water, fill it back up which should buy you time to get somewhere proper at normal operating temperature.

[Felix_29]

The coolant was dripping from around the rear axle, not very much. I put a bucket under to catch it but there isn't really anything leaking. By the time I got home the engine temp guage was off the charts. I was only in the car roughly half hour. Hopefully i'm not gonna need a new engine now.

[sdg3205]

Pull off your oil cap and see if the plastic screen is still in tact - not that it'll tell you much but I've heard it's used as an indication of overheating vs BADLY overheating.

Once you use a pressure tester that leak will show up quickly.

[jmettee]

By the time I got home the engine temp guage was off the charts. I was only in the car roughly half hour. Hopefully i'm not gonna need a new engine now.

UGH, I'm sorry, but why do we see posts like this pop up every 6 months? I thought everyone knew that driving on an engine that is overheating is not good. The thing to do is pull over IMMEDIATELY, not get home & hope for the best.

I hope the best for you, but it sounds like you lost coolant & cooked the engine if your temperature gauge was pegged past the highest mark. If your gauge didn't actually get all they way up, you have some hope that you didn't damage it too bad.

As the others said, rent a coolant pressure tester & find the leak(s). Also, check the oil to see what i looks like. If it's milky/foamy brown looking, you're likely looking at an engine rebuild.

[DeLorean03]

Hey bud. Wow, that is a scary thing to go through. I've been in my car a good 4-5 times and had the car overheat or begin to overheat too. If you didn't "peg the temperature gauge out," then you are all right. What sdg said is VERY good advice, pull the black oil cap where you refill your oil. There should be a little plastic sieve-like screen in there. If it is intact, you should be (I'd say 9 out of 10 chances) good. If that thing is a mess or is just a mound of melted plastic, eek ): ...

As others have stated, snag one of these coolant system pressure checkers at your local AutoZone:

http://www.nhproequip.com/i/uploads/1553.jpg

You can rent them for free. What happens is you give them $85 and take the tool home. You can then choose to keep the tool and be basically have paid for it, or you take it back and they give you a full refund.

Something somewhere went awry in your cooling system - either loss of coolant (doubtful since you said you saw some dripping out of the car) or something electrical malfunctioned (more probable). Refill the car with coolant, check your oil sieve-screen or your oil to make sure "coolant and oil haven't mixed" and then start your car. Wait for the temperature gauge to hit 220 degrees. Your cooling fans should come on. If not, we need to start diagnosing what is not behaving in your system.

Another possibility is your have air in the system - this little kit will fix that:

http://specialtauto.com/delorean-parts/images/air-bleeder.jpg

Snag that at specialtauto.com under the "DeLorean Updates" page for $25. It's called the "air bleeder kit", and you won't have to really ever worry about air bubbles getting caught in the system ever again (99% of the time - there's always some wild exception). Once you have that to auto-bleed your system and your engine is running fine, we can figure out if it's a coolant leak causing loss of coolant and your engine to overheat, or if your fans are not coming on allowing the engine to overheat.

Either way, we can help you. We're here for ya :thumbup:!

[DeLorean03]

UGH, I'm sorry, but why do we see posts like this pop up every 6 months? I thought everyone knew that driving on an engine that is overheating is not good.

Maybe the fact that his join date was today and he has a grand total of 2 posts - both on this thread - have something to do with it. Poor guy was probably freaked out that his stainless baby was overheating and didn't know what to do. What is obvious to you or me may not have been obvious to him. I understand that seeing the same ol' "rookie mistakes" can get a bit irritating, but also remember we all started somewhere, and this guy is just trying to learn what to do.

He came for help - let's help him.

[Michael]

My wife lost a lower coolant hose on our old Honda and the thing ran dry in a matter of seconds, the engine got so hot it started detonating but she kept driving it and called me. She reported the temp gauge was normal, and it was making a wierd "clanking sound"...which was the engine detonating from the heat. Happy ending though, the engine and head gasket was fine but then again,... it was a Honda.

One thing to remember in the future is the temp gauge shows the coolant temp, not the engine temp. If you lost a lot of coolant very quickly, you can show a normal temp reading, and it wont start climbing until the remaining coolant starts to steam and finally raises the gauge...of course by the time that happens, it's too late.
Rule of thumb, if you see the temp climb past the 220 mark(especially if you are moving, mine hardly ever climbs much above the first mark except when I am stopped in traffic), don't wait and don't chance it... shut it off, because the engine temp. may be much higher than what the gauge is showing.

[Felix_29]

Hi guys, thanks for your help. I did check the engine oil filler cap and the plastic sieve is fully intact. Also I checked my dipstick and my engine oil is still golden, no milk or foam. I think that is a good sign. I have some friends coming over to help me with the car tomorrow. I will keep you updated.

[Bitsyncmaster]

I had started a what to do if ???? in the old forum and engine overheat was the number one instruction.

So you new guys need to know this.

If your temp gauge suddenly shoots up, IMMEDIATELY PULL OFF THE ROAD AND SHUT OFF THE ENGINE. Find the problem (often just a broken belt) and do not drive the car until you have it fixed. A tow home is much less costly than an engine rebuild.

Also in any car you suspect to be overheating, turn off your AC. Your AC heats up the the air passing over the engine radiator so even with a dead cooling fan turning off the AC will help cool the engine.

[Patrick C]

Also in any car you suspect to be overheating, turn off your AC. Your AC heats up the the air passing over the engine radiator so even with a dead cooling fan turning off the AC will help cool the engine.

I disagree with this one. Turning on the A/C kicks on the cooling fans and drops my temp gauge very quickly (especially when the engine is getting really hot in a parade type of setting.)

[mluder]

This extact same thing just happened to too. I topped of my coolant to get home - need to do a propper bleed and re-fill next.

In my case, I think it may have gotten so hot it blew out my clutch slave cylinder too as I am now leaking clutch fluid. Anyone ever heard of on overheat casuing that before?

I also think the engin bay got so hot it changed the shape of the louver because it was binding on the t-panel and wouldn't open. After it cooled down it opened just fine.

Weird stuff. Nedless to say I am currently very angry at my car.

Steve

[Bitsyncmaster]

I disagree with this one. Turning on the A/C kicks on the cooling fans and drops my temp gauge very quickly (especially when the engine is getting really hot in a parade type of setting.)

Only if the failure was caused by a bad otterstat or it's wiring.

Running the AC in my car will also drop the temp a little sitting at a stop light but I'm no where near any overheat condition.

[dvonk]

if i notice an engine is running hot, i crank the thermostat to 'heat' and turn the blower motor on full. the heater core helps pull some excess heat out of the cooling system. not sure if it is super-effective, but i think every little bit helps as you are pulling over.

[Bitsyncmaster]

if i notice an engine is running hot, i crank the thermostat to 'heat' and turn the blower motor on full. the heater core helps pull some excess heat out of the cooling system. not sure if it is super-effective, but i think every little bit helps as you are pulling over.

Yes, that would also help as long as you still have coolant.

[Canon20DFan]

I have never heard or thought of that - loss of coolant would leave the temperature gauge at normal. Geez. Am buying external/internal engine block temperature sensors and wiring them to the car. Expect to see a product on DPI's website soon, I'll be working out a deal...

One thing to remember in the future is the temp gauge shows the coolant temp, not the engine temp. If you lost a lot of coolant very quickly, you can show a normal temp reading, and it wont start climbing until the remaining coolant starts to steam and finally raises the gauge...of course by the time that happens, it's too late.

[go_leafs_go]

Hi Felix29,

I just went through this nightmare myself...I feel your pain.

Get the car up on a hoist and check the condition of all of the hose clamps and hoses. If any of the hoses are bulging, they need to be replaced.

Do the pressure test...It will tell you where the leaks are in no time.

Check if you have the original radiator...If so, it may be crusted with debris/deposits as mine was. Do not assume that it is ok because the previous owner said it was.

Check your thermostat...Put it in a pot of boiling water and see if it opens up.


Good luck,
Dean

[John U]

Glad to see it sounds like no permanent damage....

Where are you located in Ontario...(This wouldn't be Kerry would it??)


John

[DMC5180]

Felix29,

You mentioned 126 Is your car Canadian Spec w/ metric gauges. If it went that high it is likely you have been loosing coolant slowly. You mentioned smoke near the stainless tank. This is another sore spot with me personally. You cannot easily check to see IF your loosing coolant, I refuse to use the Metal tank for that very reason and am glad that DMCH/EU has reproduced the Plastic tank w/ modern Materials. I am always looking to see if AFTER a drive and Cool down, that the level is the same as the last time I checked it. Btw your dripping near the axle could be from coolant running forward on the frame from the Overboard hose after it got so hot it started blowing off pressure or coolant running down the coolant pipe on that side from a loose hose connection.

[Jimmyvonviggle]

The first thing I would do is to fill up the cooling system (when car is cool) and trace to see if any fluid leaks from any hoses. Once you are sure there are no ruptures or pinhole leaks, than I would run the car again and see if it starts to get hot again. Of course do not wait till the temp goes into the danger area. You will know being your car what is an abnormal temp reading. If it goes hot agin shut it off.


You now have the choice of a bad radiator, bad fans, or bad thermostat (most likely) as the most likely culprits.


Good luck.


#3028

[Felix_29]

Yes it is Kerry. The car is from the U.S. but the car had metric instrumentation installed afterwards.

[DMC5180]

[QUOTE=Jimmyvonviggle;8577

You now have the choice of a bad radiator, bad fans, or bad thermostat (most likely) as the most likely culprits.

[/QUOTE]


Bad radiator- Not Likely, unless it were somehow plugging up. That would show up as a trend of increased running temps (loss of efficiency). A leak would show up as green puddles on the ground.

Bad Fans- One fan will cool the car. for both to fail themselves would be unlikely. A bad connection upstream as a Single point failure in the Relay compartment or a failed Otterstat (open) would cause the fans not to run. That is not Bad Fans.

Thermostat- Most fail in the OPEN position which doesn't allow the engine to warm. Although I did experience a case where a thermostat was slow to open. It did Open but at a higher than normal temp when compared to a new replacement.

What seems to have happened here is a slow loss of coolant to the point that it was too lower in the system and overheated or a loss of the fan operation which would cause a rapid temp increase. One of the things this car needs is an "ATTENTION" getting temp light. Even my Daily driver 93 Cougar has a "CHECK GAUGES" light that comes on if any gauge (low fuel, low oil and High engine temp)is out of the normal range.

[mluder]

I have never heard or thought of that - loss of coolant would leave the temperature gauge at normal. Geez. Am buying external/internal engine block temperature sensors and wiring them to the car. Expect to see a product on DPI's website soon, I'll be working out a deal...

That would explain why when I did the temporary refill in the Target parking lot (didn't bleed and fill) my temp stayed pretty low even though when I got out, the engine bay was super hot.

Steve

[Masaes727]

I had the stove pipe come loose where it connects to the header. Not something that was easily noticed. It managed to rub against the cooling pipe that comes from the coolant bottle and put a hole in it. Which resulted in a loss of coolant, with lots of smoke/steam. Anyone tried to find one of these pipes?? Good luck. However, I do now have a spare one. Albeit with a small hole in it, but I am assuming it could be welded and pressure tested to ensure a good seal. As a temporary fix, I applied jbweld, the kind that can be used in marine applications. Then cut a coolant hose and secured it north/south of the hole with clamps. Not a good fix, but it held and worked fine until I was able to acquire a coolant pipe set.

[DMC5180]

It's pretty common for that heat stove pipe to chafe a hole in that rail pipe. It happened to me and couple other people I know. I welded mine but it was a pain because of contamination porosity in the weld area. Aluminum must be clean of all oxides for proper welding. The issue was mainly with build up inside the pipe that could not be cleaned thoroughly. I'm surprised DMCH hasn't reproduced a small quantity (25) to make them available. Since it is very common issue. A Local pipe shop could Fab them up for a reasonable price.

[John U]

Felix,
Is you car under warranty still from dmcfl?
Did you get your axel boot replaced? And find out if the TABS were replaced?

John

[WelmoedJ]

In my case, I think it may have gotten so hot it blew out my clutch slave cylinder too as I am now leaking clutch fluid. Anyone ever heard of on overheat casuing that before?
Steve

When my propellor ran off of the fan motor, the temperature rose to 220F.
Thereafter trying using first and reverse gears from full stop got hard (grinding).
Once rolling no shifting problems.

Some guess this is due to still having an old type clutch line expanding if the fluid gets hot, but it's working properly if the temperature is normal.

I assume heating up the engine causes this kind of problems with the slave clutch cylinder (perhaps due to water in the fluid? Even though the fluid is rather fresh: not older than one year).

[Felix_29]

I got my car back from the mechanic today. He said there was no damage to the engine. I am noticing two things.

1. I can't detect that the fans are coming on intermittently which I use to notice.

2. After a drive and I come home and put my car into park my Idle goes up to about 1500 RPM. When I start the car it is idling in the normal 750 Range. and the car will idle when stopped at intersections.

Felix

[Cory W]

I got my car back from the mechanic today. He said there was no damage to the engine. I am noticing two things.

1. I can't detect that the fans are coming on intermittently which I use to notice.

2. After a drive and I come home and put my car into park my Idle goes up to about 1500 RPM. When I start the car it is idling in the normal 750 Range. and the car will idle when stopped at intersections.

Felix

Good news there was no damage! Hope to see you at Bronte in September! 30 for 30!

1) Can you still HEAR the fans kick in, though? Are they still kicking in at a regular temperature? Do they still kick in when the A/C compressor cycles?

It's possible you had air in the system that kept the fans guessing, so they'd intermittently kick in. This is a complete and total guess on my part.

2) Can you blip the throttle back to 'normal' from 1500 RPM? I'm assuming at intersections "will idle" is its normal idle?

[Farrar]

You might want to also check all of the diodes in that circuit to make sure that they're working properly and you have good continuity.

Farrar

[TTait]

I have never heard or thought of that - loss of coolant would leave the temperature gauge at normal.

Oh boy does it ever. I was cruising one day on the 405 freeway, probably 70 mph and a guy pulls up along side and gestures to put my window down. He says I just dumped a couple gallons of gasoline all at once. ???

The gauges all looked fine, but I took him at his word and pulled off immediately for a look see. He thought it was gas because it was at the rear of the car, it wasn't - it was virtually every drop of coolant. The clip that holds the otterstat came off and the otterstat shot out, followed by all my coolant forced out at 15psi. The system emptied so fast I never saw a thing. The really scary thing was that the temp gauge in the dash never even quivered. With no water on it there was nothing to show that the engine was about to melt down.

Fortunately the otterstat and seal were hanging from its wires, I plugged it back in and secured it with a cable tie (everyone PLEASE do this NOW - align the otterstat so one terminal is toward the front of the car, and the other toward the back - put a cable tie around the pipe and between the two terminals, then put the wires back on.)

I walked to a nearby 7-11 and bought two gallons of prestone and two gallons of water, refilled and drove it home no problem - the whole incident lasted 30 minutes including walking, filling and bleeding.

In this case, a coolant pressure gauge, low coolant level sensor, or oil temp warning light might have helped if we had any of those.

As far as bleeders, another thread recently had to get shut down because people were getting way too intense. To summarize - a bleeder can mask other problems in your car like a blown head gasket or a leak - this is NOT why you install a bleeder - bleeders are installed to be used as a tool when refilling a properly maintained system, not to alleviate other problems.

The thermostat bleeder hose is now sold by some vendors with a shutoff valve in the middle so it is only open when intentionally bleeding during refilling. There is also a radiator bleeder kit available from Toby at DMC-NW (he actually sells both kits). This is a very valuable tool to aid in bleeding air out of the radiator. It is not active at all times and is not sold as a treatment or cure for any known disease. Weight loss results are not typical.

Also worthy of consideration are the sight tubes Hervey can install in metal tanks - I have them on both cars for many years. They let you see how much fluid is in the tank without having to open it. You can not open a the metal tank on a hot system or it will spew coolant on you and burn you. Burning hurts. Without this tube installed you must wait for the system to cool before you can see if your level is low. With it you can see at an instant at any time. They do not leak. Its a no-brainer to me.

Also you might consider installing a coolant overflow tank - Again I have them on both cars and they work well. With an overflow tank you need a pressure cap with a secondary rubber seal in it. You also run the car with the metal tank full of coolant, not half full. Photos available if needed.

A note on coolant mix. 50/50 is best right? Even stronger would be even better, right? I mean if some is good more must be better. Whoa! Its actually a balancing act. Pure water is actually better at transferring heat than coolant. An engine running just distilled water will notably cooler than a car with a 50/50 mix - BUT - once the water gets up to near 212(ish) degrees it starts to boil - and your screwed. Antifreeze keeps the water from boiling until say 270 degrees, prevents freezing in cold climates, and has additives that prevent corrosion - but its not as good at transferring the heat around.

If you live in a hot climate you might consider a 30/70 antifreeze to distilled water mix - the car will run cooler. If it does overheat it will boil at a lower temp, but the trade off is that it does run cooler and is still technically less likely to overheat. Do the research and you decide. If your running hot though, don't think that more than 50/50 is helping you.

You can add a products to the coolant as well - I'm testing out DEI Radiator Relief (similar to water wetter). Its an additive that makes the coolant (water, antifreeze - whatever mix you have) transfer heat more efficiently. It makes you coolant get warmer faster after starting up, and then once the thermostat opens it allows the coolant to chill more when going through the radiator. Its magic!

I have changed recently to a 30/70 mix and a bottle of this product and the car seems to be running noticeably cooler. That is, it warms right up to 195 on a hot day, but then it stays at 195 longer than it used to. On a really hot day sitting in bad traffic the temp is slower to come up and it doesn't go as high as it did before. Occasionally I had to shut down the AC and turn on the heat even with a newer and well maintained cooling system. (125 degrees plus on the freeway) It SEEMS to work well - but it's early yet. Lots of good reviews on the net and the manufacturer swears its compatible with all metals in our engine. In theory you can run it with just distilled water and get great results, but I'm not that crazy.

I'll let you know.

Please note I do not suggest using this product, bleeder kits or a coolant recovery tank as a band aid to try to work around a larger problem - you need a good cooling system first. No hating.

[Bitsyncmaster]

Good idea. Think I will safety-wire my otterstat. Not sure how a cable tie will hold up.

[WelmoedJ]

Good idea. Think I will safety-wire my otterstat. Not sure how a cable tie will hold up.

Over here in Europe cable ties are widely used.
Not the tiny ones, but the large ones (approx. 4-5 mm width / ± .40").

[Farrar]

For the above-mentioned reason and just for curiosity, I have considered using a temperature sensor with a ring terminal with some sort of readout inside the car to use as "engine temp" in addition to the stock "coolant temp" gauge. If I ever figure out how to manage this, I will post the results here.

Farrar

[WelmoedJ]

Because of the vulnerability of the mechanical otterstat I replaced it - as mentioned previously and in another thread - by an electronically version.
The electronic version is part of the pipe and therefore only a defective hose is capable of causing a sudden drain of cooling system.

The piece of pipe in which the original otterstat had been, has been replaced with a piece of pipe with no holes (like the original one).

Ergo: little chance of having a sudden leak due to an otterstat popping out of its fitting.

[TTait]

Good idea. Think I will safety-wire my otterstat. Not sure how a cable tie will hold up.

I cut my cable tie off the other day - its been on there for 2+ years and it was perfect. I wouldn't worry about cable ties at all. If you choose a wire instead, pick an insulated one. Its unlikely that it will contact the terminals n the switch, but it could.

[Bitsyncmaster]

I cut my cable tie off the other day - its been on there for 2+ years and it was perfect. I wouldn't worry about cable ties at all. If you choose a wire instead, pick an insulated one. Its unlikely that it will contact the terminals n the switch, but it could.

Good idea. Could just put a small length of heat shrink over the wire. I have standard aircraft safety wire which is stainless steel.

[DeLorean03]

Had a cable zip tie on mine for 4 years. Replaced it back in 2008 with a new one. I have had zero issues. I have a razor knife in the DeLorean JIC I have to cut it off.

[David T]

There is usually no issue if the clip is properly snapped on. If you don't have one a zip tie (strap tie) is fine. When I first did my otterstadt switch I though a small smear of silicone would help make things go together easier and seal better. BIG MISTAKE. The seal ripped very soon because the silicone reacted with it. I also had an otterstadt crack and leak. Just another area of the car to inspect regularly. 50/50 anti-freeze and water will go to 256 degrees F at 15 psi. Any other ratio will not get you as much on the high side. When you suddenly lose pressure all of the coolant will flash into steam and blow out of the system rather quickly in an impressive cloud. Happened to a Delorean on a FFT in Provincetown when his left radiator tank blew off in traffic! Couldn't see ANYTHING for a moment till the cloud cleared. Also another reason you want to get rid of the plastic header bottle. When it blows up you will again, lose all of your coolant. All of these things and more are just good reasons to properly service and maintain your cooling system.
David Teitelbaum

[sdg3205]

Not sure if I'm the only one, but use the right hose clamps too.

I ended up loosing 1 or two of the hose clamps that came with the DMC kit so I substituted them with the best I could find at our Autozone equivalent. Can you guess which ones leaked on me?

The shitty ones have perforations in the metal as opposed to the ribs the DMC ones seem to have.

[Canon20DFan]

Can someone post a quick photo of the cable-tied otterstat?

Good idea. Think I will safety-wire my otterstat. Not sure how a cable tie will hold up.

[TTait]

here ya go... Note that you can keep the factory clip too.

i wouldn't worry about heat, this cable tie has been on since 2007. A quick google shows that nylon cable ties don't melt until 430 degrees.