In theory, if my head gaskets were damaged... I should be seeing or smelling coolant in the exhaust correct?

That depends on which area of the Head Gasket is Damaged.

 

One of the two headgaskets on my "BumbleBeast" failed in December 1994, and the only symptom was that it was Blowing all the coolant out of the engine, after reaching normal operating temperatures, the coolant blew from an area nearby the exhaust on one of the Heads, to the open air under the car, but never smelled nor found mixed coolant with oil; I wrote the full story regarding that ~► Here, on my build tread.

 

So, there are some different ways that a Head Gasket could fail; also, I've seen in other cars, that the cooling system gets excessive pressure and blows the coolant to the reservoir bottle, and usually ends blowing one of the radiator tanks; the cause is exhaust gases that gets onto the coolant passages...

 

Kind Regards.

► Edited to add the web link to the word "Here".

Edited September 22, 201510 yr by Loyale 2.7 Turbo

Sapper 157, on 22 Sept 2015 - 11:03, said:

In theory, if my head gaskets were damaged... I should be seeing or smelling coolant in the exhaust correct?

yes, correct.

 

if the leak is from coolant side into combustion side, but think about min 160 psi combustion pressure V's 13 psi coolant pressure - be more likely to be blowing combustion pressure into coolant.

 

Can also get oil in coolant coz oil pressure greater than coolant pressure most of the running time. and the common reverse, coolant in the oil coz when you shut down engine, coolant still has pressure, oil does not, takes easy path to the bottom of your sump. Next start up unknowingly mixes coolant and oil under heat and pressure

 

Then, can also get leaks from one pot to its next door neighbour - showing up in comp tests esp if next doors plug is out

 

other leaks can be

Edited September 22, 201510 yr by jono

As the heavy hitters above me have posted, HGs can fail in a number of ways. In my experiance most issues Ive run accross left me debating if there was actually an issue. Your not always lucky enough to have mixing of fluids or billows of white smoke that scream "failure".

The most common complaints are occasionally running a little hotter than normal and bubbles or foam in the coolant. This usually comes with a slow loss of coolant. The tail pipe may smell acridly sweet even after sitting over night. Pulling the dipstick or oil fill cap with the engine running may reveal odd ticking wissing sounds. Its all just evidence tho, and means little. One thing has served me well in prossecuting such a case is test strips.

Do you have an issue or are we just chatting?

Headgasket failures I have experienced:

 

Cylinder/s to coolant - the most common.  Anything from a very small slow little bubbles in the coolant recovery bottle, to pushing the coolant out fast enough to overheat in a handful of miles.  Once it starts with the small leak, it grows until unusable.  It may be a few days, weeks or months.

 

These leaks invariably began after a mild overheat due to low coolant, usually caused by an intake gasket failure, coolant system hose failure, radiator leak, water pump seal failure.

 

Checking coolant level 1 time per week is not frequent enough to catch many of the leaks that I have had cause failures.  I check coolant in the morning.  Both by looking at the level in the bottle, and by squeezing the upper hose.  [Do I hear air, water, etc going through the jiggle pin?]

 

Water jacket to exterior.  A few  times.

 

Water jacket to oil sump.  Once, with a bad overheat with very low coolant.

I have not had a headgsket failure that caused coolant to be burned and cause detectable evidence in the exhaust.  I have had an intake gasket fail and cause the smell & smoke.

As the heavy hitters above me have posted, HGs can fail in a number of ways. In my experiance most issues Ive run accross left me debating if there was actually an issue. Your not always lucky enough to have mixing of fluids or billows of white smoke that scream "failure".

The most common complaints are occasionally running a little hotter than normal and bubbles or foam in the coolant. This usually comes with a slow loss of coolant. The tail pipe may smell acridly sweet even after sitting over night. Pulling the dipstick or oil fill cap with the engine running may reveal odd ticking wissing sounds. Its all just evidence tho, and means little. One thing has served me well in prossecuting such a case is test strips.

Do you have an issue or are we just chatting?

Explain to us all how the test strip helped diagnose please

As the heavy hitters above me have posted, HGs can fail in a number of ways. In my experiance most issues Ive run accross left me debating if there was actually an issue. Your not always lucky enough to have mixing of fluids or billows of white smoke that scream "failure".

The most common complaints are occasionally running a little hotter than normal and bubbles or foam in the coolant. This usually comes with a slow loss of coolant. The tail pipe may smell acridly sweet even after sitting over night. Pulling the dipstick or oil fill cap with the engine running may reveal odd ticking wissing sounds. Its all just evidence tho, and means little. One thing has served me well in prossecuting such a case is test strips.

Do you have an issue or are we just chatting?

i might have an issue. It keeps getting warm on me and I have replaced the stat and flushed the system but it still seems to be getting warm. Today I took the rad cap off and let it run up to temp to get any air bubbles out. There were quite a few bubbles and then it kinda got better the longer it ran. My worry is that what I saw was not air bubbles but warning signs of a blown HG. If I run it again tomorrow and get the same results, then I guess I got a blow HG huh?

The longer it is ran the worse the bubbles will get if it has a blown head gasket. I had a bad block in my ej'd hatch that was putting so much exhaust gasses into the coolant it was boiling in the upper radiator hose and shooting out the radiator about 3ft even if you rev it from idle to 1500. That was running at a little above half way on the gauge.

Explain to us all how the test strip helped diagnose please

misprint, sorry (I have kids) not sure why that came thru. No strips that Im aware of can test for gasses in fluid. PH not gas.

Test kits on the other hand... I have something like the unit in the link with a bulb, tube and juice. Drain some coolant warm it up and do the test. Is this test 100%? Does it cost more than the gaskets?

 

http://www.amazon.com/Lisle-75500-Combustion-Leak-Detector/dp/B0007ZDRUI

i might have an issue. It keeps getting warm on me and I have replaced the stat and flushed the system but it still seems to be getting warm. Today I took the rad cap off and let it run up to temp to get any air bubbles out. There were quite a few bubbles and then it kinda got better the longer it ran. My worry is that what I saw was not air bubbles but warning signs of a blown HG. If I run it again tomorrow and get the same results, then I guess I got a blow HG huh?

Have you confirmed that its actually running hot? Forget the gauge on the dash.

Have you confirmed that its actually running hot? Forget the gauge on the dash.

Oh.... well if we are forgetting the gauge on the dash then I honestly have no clue if it is actually getting warmer than normal. 

http://www.ultimatesubaru.org/forum/topic/154693-86-brat-overheats-after-clutch-replacement/

I have noticed that the gauge on the dash, from car to car, is not calibrated. That is, half way up on one is normal, half way up on another is overheating. BUT on any ONE car, if it is normally say, at half, but then something is failing, and it starts reading higher, it is displaying that information correctly, that the engine is hotter than normal. Running hotter than normal is bad for these engines. That's what I have seen since 1988, over 7 EA82 wagons.

When the leak is small, checking the coolant level and air in th hose, before every run tells more than a one time check.

Agreed, any noticeable consistent change in readings is not a good sign. But using the stock ea81 gauges to diagnose an HG would be a poor choice. I posted a link the above thread since its an epic example of what Ive seen with my cars.

Okay so I am almost certain that it is a bad HG. Today I took the cap off and brought the RPMs up to about 3000. The higher the rpm got, the more bubbles came.     

So I dont think im gonna like the answer to this but do I have to pull the engine to change the HGs?

... I took the cap off and brought the RPMs up to about 3000. The higher the rpm got, the more bubbles came ...

 

Bubbles on Radiator also might be due to a stuck open or failing Thermostat as well.

 

This issue needs better diagnosis, in my own humble opinion.

 

How about a Compression Test?

 

Kind Regards.

Bubbles on Radiator also might be due to a stuck open or failing Thermostat as well.

 

This issue needs better diagnosis, in my own humble opinion.

 

How about a Compression Test?

 

Kind Regards.

Your humble opinion is worth a lot to me Jeszek. So i will diagnose it farther. The thermostat should be good.. I replaced it two weeks ago with a super-stant 180 thermostat. I will try to get a compression test done

Your humble opinion is worth a lot to me Jeszek ...

 

Thank you for your kind words.

 

Usually the Aftermarket thermostats are not as good as Genuine Subaru ones, however Stant is a good brand, as far as I know.

 

I kindly suggest you, in order to better diagnose this issue, that you might run your Subie's engine, without thermostat for some days; after all it won't hurt anything; also you might borrow a digital (infrared) thermometer; with those two things, you can check better the amount of coolant usage, also monitor better the temperature fluctuations; but you'll need to drive the car a little Hard, in order to let it develop the issue, either a coolant loss and / or abnormal raised temperatures under load.

 

~► http://www.aa1car.com/library/tstemp.htm

 

Kind Regards.

Got to agree with what DaveT said about the gauges from car-to-car.

It also varies engine to engine I have found.

 

Same car, same temp sender, 3 different engines. All read differently on the temp gauge.

 

Oil pressure readings varied also. Not a lot, but different.

... Same car, same temp sender, 3 different engines. All read differently on the temp gauge ...

 

Yes, that's true, it depends on which kind of Radiator did the factory fitted to the EA82, they used either a two row and a single row radiators; also depends on the Model; certain DL's doesn't have mechanical (pulley driven) Fan, only the electric one...

 

Kind Regards.

The pinhole small bubbles in radiator won't show on a compression check.  When it gets worse, yes.  The easiest  way to tell is how fast does coolant disappear from the recovery bottle over a few drive cycles.  Is there more or less air in the upper hose each time?  When this failure gets toward the bad range, so much "air" get pushed into the coolant system that a short drive will cause the recovery bottle to overflow.  At this point, there is no question.

 

I have always resealed a spare engine, then swapped it.  Yes, it can be done on the car, but it's a lot easier to get at and see everything on a stand.

Yes, that's true, it depends on which kind of Radiator did the factory fitted to the EA82, they used either a two row and a single row radiators; also depends on the Model; certain DL's doesn't have mechanical (pulley driven) Fan, only the electric one...

 

Kind Regards.

For some reason I only have one electric one. It used to be the standard four blade one but I replaced it last year with an $80, 10 blade, Flex-a-Lite fan. I want to get a second electric fan to offset not having a mechanical fan, but lack of funds has diminished by ability to upgrade

This is where I use OEM gaskets also.  Just my opinion.