Running out of water as bad as out of oil?

[Cup O Noodles]

I've driven non-Subaru vehicles out of water before and they steam really bad and the engine shuts off. After it has cooled I would fill up the radiator and be off again. Obviously, the engine still worked but this was years ago and now I'm being way more careful with my cars and learning proper maintenance.

 

I just drove from Eugene to Portland and back (200 miles) and everything seemed fine. I even made a stop 10 miles before getting home and nothing was wrong but when I parked in my driveway I heard the hsssss and saw some steam. I popped the hood and the everything on the passenger side was wet.

 

A few days later I filled the radiator with a gallon of water and filled the coolant tank/reservoir. The engine runs fine (thanks GD for fixing the vacuum leak) but I was wondering if I might have damaged the engine? Also, I couldn't find any evidence of a leak in the radiator.

 

Is running out of water as harmful to your engine as running it out of oil?

[EvilDead]

On aluminum block/head engines it's pretty darn bad to overheat. Warpage is the culprit. If ya are losing water, and the rad isn't leaking, I'd check those pesky head gaskets, or possibly a hose has gone to poo. Could be a number of things.

 

Running out of oil can do equal amounts of damage, but in different ways. Spun bearkings etc.

 

Both are really a no no, and should be avoided at all costs. Watch that temp gauge! If it's not working, fix it.

[idosubaru]

steam and adding water isn't important, what's important is did the car overheat or run hot?

 

"running out of" is ambiguous, so I wouldn't compare other experiences. there isn't much to take home from correlating those events.

 

i've seen Subaru's quit running due to trying to run them while overheating (even an EA82 which is what you're probably talking about though you don't mention what vehicle/engine). then a refill and fix whatever caused the coolant loss and they're fine. that's anecdotal though - to expect that all the time is plain silly, it's definitely not the norm.

 

running low (coolant or oil), to the point that the system can not operate as normal - is really bad. running low on coolant is more risky with age too - 20+ year old gaskets are not as good as 1 year old gaskets.

 

if you're paying for maintenance yourself both will easily cause very expensive repairs that pretty much render most old gen subaru's worthless.

 

if you can do the maintenance yourself then overheating is a little bit "better" because it's usually headgaskets that go first and that's much simpler and cheaper than engine replacement/rebuilding that oil loss will cause.

 

sounds like you have a leak or lost enough coolant for it to boil and push out of the overflow tank. find the source of your coolant loss and fix it. 20+ year old gaskets don't hold up well to heat.

 

if you overheated it badly i'd change the engine and transmission oil soon, heat doesn't do good things to metal or oils.

[Twitch de la Brat]

It can be as Gary said.

 

Ironically enough though, I have run my BRAT completely out of coolant/water

and still was able to drive it 10 highway miles back to work without overheating

it

 

Now that is an EA81, not an EA82, but in theory you could get away with

running it out of coolant as long as you could keep it cool.

 

But running out of oil is a whole nother story and will most likely cause massive

internal damage to the engine.

 

Twitch

[Cup O Noodles]

Thanks a lot. It's an '87 GL.

[GeneralDisorder]

Could be a pinhole leak in a hose - there's been quite a bit of cooking going on in your engine bay so it could be one of the hoses under the manifold, etc that carries coolant to the bottom of the carb...

 

If it was still steaming and hissing when you parked it then that's a good sign - means there was still some coolant in the engine .

 

As long as the gauge didn't climb and the engine kept running - you are fine. They will lose power and basically stop running right if they truely run out of coolant and an extreem overheat results.

 

I wouldn't worry about it other than to note that you probably have a coolant leak and you should try and find it and certainly keep it filled and keep extra coolant with you in the car.

 

GD

[idosubaru]

Now that is an EA81, not an EA82, but in theory you could get away withrunning it out of coolant as long as you could keep it cool.

glad you made it safe out of that one, got lucky like i did (the EA82 example above was my first Subaru!). staying cool isn't the entire equation. if the gauge looks okay or are staying cool some way, the lack of circulation or poor flow can cause localized overheating.

 

overheating damage may not show up until later, 10k, 50 k, etc. EJ25's are a great case in point, with their propensity to overheat immediately, they get overheated a lot. and they loose a lot of rod bearings later in life too. i picked up a 57,000 mile GT that had the headgaskets replaced at 20k or 30k. and that kind of scenario is very common, not just anecdotal.

 

but like you, i've seen it as mentioned a couple posts ago, in an EA82 as well. this info is all well and good, just let it inform your current predicament, not future neglect.

[Gloyale]

It worth noting that if you put a weak, watered down mix (or straight water), you will eventually lose it and start overheating. Espescially in a Subaru.

 

Water boils at 212. But we all know from boiling water that it begins to steam and bubble a bit before the actual boiling.

 

Normal engine temps are from 190 to 210 ish. So basically on a hot day, working the engine hard, it doesn't take much to push the water to a boil......where it steams out......and then because it left as vapor and evaporates, never get's sucked back in the rad from the overflow bottle.

 

The cycle repeats day after day, trip after trip, until the coolant is so low that the engien REALLY starts to get hot.....at which point the boiling water thing becomes and exponential problem.

 

The glycol in coolant raises the boiling point to 250+

Run strong mixes.....at least 50/50 coolant/water mix and up to 70/30. (after that point cooling will be diminished from stronger mix)

[idosubaru]

all that boiling of water leaves mad residue inside your system too unless you're using distilled water which many don't do.

[presslab]

Losing water can be bad... But if your temp gauge didn't get in the red you should be ok.

 

Glycol does raise the boiling point, but so does the pressure inside the cooling system. The absolute pressure is about twice that in normal atmosphere. This raises the boiling point further by about 20 C or 36 F, so the boiling point of straight water would be 248 F without any glycol.

 

If you have a leak and pressure is lost, the boiling point will go back down to 212 F. So it's always a good idea to run glycol mix, unless you are on a race track as they don't allow it for safety reasons.

[Cup O Noodles]

Thanks for all the advice. The coolant tank was totally empty so I suspect there was very little in the radiator and that's probably why all the water boiled off, or almost did. I'm going to keep an eye out for a possible leak, though and will probably change the head gaskets anyway.

[GeneralDisorder]

I doubt you need to do HG's. Probably just replace all the coolant hoses (your engine looks really cooked so they are probably all rock hard) and do something about that lifter(s) .

 

The coolant "tank" is for expansion - it being empty is a sign that there's a leak or that it was low when filled and the radiator sucked all that coolant in when it cooled. The fact that you saw steam would seem to indicate a leak. At this stage though I wouldn't suspect HG's if you aren't overheating.

 

GD

Edited September 6, 2010 by GeneralDisorder

[Cup O Noodles]

I found a leak. A worm gear clamp was loose. I think I'll take your suggestion GD and replace all the hoses.

 

Also, I noticed a recess on the passenger side of the radiator right about in the middle. It looks like it should be plugged up but nothing was leaking out. I haven't looked at it with the engine running yet but I'll do that tomorrow unless I hear back that it's just a valve or something.

 

Thanks.

[GeneralDisorder]

Also, I noticed a recess on the passenger side of the radiator right about in the middle. It looks like it should be plugged up but nothing was leaking out.

 

Yeah - check it with the engine running - hard to say what it is but maybe associated with the fan thermoswitch? IDK - there are too many radiator variations and most cars have had the radiator replaced at least once by that age... could be a lot of things.

 

GD