What are the definitive tests for detecting blown headgasket?

[EricV]

I'm the guy who was having the leaking aux pump that ended up bypassed. That, BTW, seems to be holding it's own. I can run/idle as long as I want and the temp needle doesn't go beyond the half mark...steady on. Oh yeah- 116K on this '93 525 5-spd.

Well, since that incident (blowing the leak on the road) I'm seeing what I'd feared- consistent white smoke, looks like steam. The temp needle that day did get up to the start of the red zone- as far as I know not into it (and it didn't blow all it's coolant...the expansion tank still had about half of what it normally does when I popped the hood and discovered the aux pump leak amidst the classic roadside under hood steaming. :) )

Now I'm used to some steam in the cool weather, but this went on and on, well after engine is fully up to temp and it's consistent. That's not my car's usual. Great...thinking the head gasket is toast. This is reinforced in reading through the threads in my search. I don't have signs of oil in coolant or coolant in oil, but as we know it can be a passage from the cooling capillary to the combustion chamber and you wouldn't have these tell tale signs. Oh, and 3-4 hours after I parked it this evening it barely had the slightest hint of pressure in it when I opened up the exp tank, so that much is good...I guess.

As mentioned I really trust my mechanic of 7 years and an hour away (a european specialty shop I've had great experiences with) so I'm thinking "just deal with it...let them definitively diagnose this and remove the guesswork."

So, what are the definitive tests for diagnosing this? I would of course defer to their expertise, but I still want to know if the tests they recommend are the best. I know of pressurizing the cylinders/looking for bubbling (and pressurization tests starting on the cooling end); leakdown test; testing the exhaust gasses/output...anything else and what's the most definitive?

Can't believe a day ago I was freaking on the inflated estimate I'd gotten for the aux pump job...that's snot compared to what this will be if it is what it seems to be. Good times... :)

Thanks in advance for any input!

Eric

[bad_manners_god]

Leakdown test will tell you for sure....if they know how to do it properly

[ryan roopnarine]

if steam is coming out, some liquid somewhere has to be fueling it. get it hot (since it sounds like you have to drive it around anyway), park it up for 2-3 hours, and pinch the top radiator hose. compare the amount of pressure it takes to pinch it with the hardness of pinching a unopened 2 litre bottle of pop and relate the experience to us.

[ss2115]

I'm the guy who was having the leaking aux pump that ended up bypassed. That, BTW, seems to be holding it's own. I can run/idle as long as I want and the temp needle doesn't go beyond the half mark...steady on. Oh yeah- 116K on this '93 525 5-spd.

Well, since that incident (blowing the leak on the road) I'm seeing what I'd feared- consistent white smoke, looks like steam. The temp needle that day did get up to the start of the red zone- as far as I know not into it (and it didn't blow all it's coolant...the expansion tank still had about half of what it normally does when I popped the hood and discovered the aux pump leak amidst the classic roadside under hood steaming. :) )

Now I'm used to some steam in the cool weather, but this went on and on, well after engine is fully up to temp and it's consistent. That's not my car's usual. Great...thinking the head gasket is toast. This is reinforced in reading through the threads in my search. I don't have signs of oil in coolant or coolant in oil, but as we know it can be a passage from the cooling capillary to the combustion chamber and you wouldn't have these tell tale signs. Oh, and 3-4 hours after I parked it this evening it barely had the slightest hint of pressure in it when I opened up the exp tank, so that much is good...I guess.

As mentioned I really trust my mechanic of 7 years and an hour away (a european specialty shop I've had great experiences with) so I'm thinking "just deal with it...let them definitively diagnose this and remove the guesswork."

So, what are the definitive tests for diagnosing this? I would of course defer to their expertise, but I still want to know if the tests they recommend are the best. I know of pressurizing the cylinders/looking for bubbling (and pressurization tests starting on the cooling end); leakdown test; testing the exhaust gasses/output...anything else and what's the most definitive?

Can't believe a day ago I was freaking on the inflated estimate I'd gotten for the aux pump job...that's snot compared to what this will be if it is what it seems to be. Good times... :)

Thanks in advance for any input!

Eric

Hi.
The first two things to look at is if there is any water in the engine oil, and then if there is any oil in the cooling system.
Oil in the cooling system will be immediately obvious by the oil slick.
Water in the oil may take a little longer to show but the oil will go milky coloured.

If there's nothing obvious there, then a cooling system check will be the next easiest to perform.
This involves two tests with a cooling system pressure guage -
1) pump up the pressure in the cooling systm and watch how quickly it drops. It should stay up for quite a long time - a good 10 minutes at least. If it drops away quickly and there's no sign of water dripping on the ground, then its probably filling up one or more of the cylinders through a blown headgasket.
2) with the cooling system pressure tester in place but not pumped up, start the engine. If the pressure immediately starts to rise and especially if its in spurts, then you can say its a blown headgasket.
If its slow to build and reaches the radiator cap pressure, you should release some pressure to the radiator cap pressure and continue to watch it for a while. If it gets to a point where its no longer building pressure, then the headgasket may be okay.

You can inspect the spark plugs for rust.
You can do compression testing and cylinder leakdown tests, but the above described tests are easy to do and revealing pretty well straight away.

The other nice thing is that a radiator repair centre can probably perform the pressure tests for you as not all mechanics carry a cooling system pressure tester.

[632 Regal]

I dont have a conclusive answer for you either, keep a watch on the coolant level but if your over heating thats not a good sign but could possibly be a water pump that took a dump.

Some hava plastic impellers that do a few different things such as slip, break and just desintregrate. I am trying to be positive and say the engine is over heating and burning excessive oil due to the overheating.

Water pumps are maintenance items so if you want to keep the car for more than a week and never performed this maintenance repair I would suggest at least that. you will know it's condition at that time. I have read all horror stories of condition.

Worse comes to worse than its a head gasket ordeal. Some say it's easy some say hard... I think with any capable knowledge of surfing the net and reading skills you can pull this off yourself with the help of the little one (dont know his/her age) with out a lot of time off of the road.

I wish the best to you and what you choose, good luck with it all.

[EricV]

Thanks guys. Ryan- I'll try that and report back.

Regal (and all) thanks as well. BTW- I did do the water pump swap to the metal impellar pump as a preventative thing a while back, and the car does not overheat at all (it's rock steady now that the bypass has been done.) The thing is the constant white smike/steam.

Yesterday it was about 55 degrees, and today we'll get near 60 and I'll be driving it more. I'll see what happens. I will sh*t the proverbial brick if this thing has blown a head gasket...I'll blow a head gasket. :)

If it is the HG...how much is a job like that? I've heard anything from 1500 to 3K. That's a lot of variance.

This place is great. Mark my words, this internet thingy is going to be big one day- big I tell you. I envision millions of people communicating all over the world about all kinds of interests/hobbies. He*l, there may even be porn on it one day. :)

Thanks all!

[whiskychaser]

If it is the HG...how much is a job like that? I've heard anything from 1500 to 3K. That's a lot of variance.


Head skim, HG, bolts, oil & filter, antifreeze, gaskets etc is under £200 if you do the job yourself. But please feel free to pay me 3000. I'd have a very nice holiday with that sort of money - but I dont think you have established the HG is actually gone yet :D

[Ross]

if coolant is getting into the combustion chambers it will always show on the plugs.
One of them very clean and especially two in adjacent cylinders is the sign.
An overpressurised cooling system, oil in water and vise versa or external leaks.
Typically it's a failure of the fire ring between cylinders.

[EricV]

Ryan (and others)- I pinched the hose an hour and 45 minutes after parking it this afternoon...not quite two hours. It's clearly soft/pliable. I can feel some residual pressure in there, but can squeeze it fairly easily. Thoughts?

Before parking it I ran it around town for about 30 minutes to make sure it was very much up to temp. When I parked it, the upper hose was pretty da*ned tight, but all looked normal. Again, after 1 hour and 45 minutes it was/is pliable.

Please let me know your thoughts. Thanks!

Eric

[ss2115]

Ryan (and others)- I pinched the hose an hour and 45 minutes after parking it this afternoon...not quite two hours. It's clearly soft/pliable. I can feel some residual pressure in there, but can squeeze it fairly easily. Thoughts?

Before parking it I ran it around town for about 30 minutes to make sure it was very much up to temp. When I parked it, the upper hose was pretty da*ned tight, but all looked normal. Again, after 1 hour and 45 minutes it was/is pliable.

Please let me know your thoughts. Thanks!

Eric

An hour and 45 minutes is too long a time - most cars will have lost pressure by then anyway due to the water cooling and sucking back water from the expansion tank.

30 minutes should be enough to test in this crude fashion.
Why don't you just call into a radiator repair shop and ask for a pressure test - it will only take 5 minutes to do and they may do it on the spot for you.

[ryan roopnarine]

Ryan (and others)- I pinched the hose an hour and 45 minutes after parking it this afternoon...not quite two hours. It's clearly soft/pliable. I can feel some residual pressure in there, but can squeeze it fairly easily. Thoughts?

Before parking it I ran it around town for about 30 minutes to make sure it was very much up to temp. When I parked it, the upper hose was pretty da*ned tight, but all looked normal. Again, after 1 hour and 45 minutes it was/is pliable.

Please let me know your thoughts. Thanks!

Eric

well, when my head was warped like a banana and didn't show any external signs of HG failure (no milkshake, nominal coolant loss, no overheating, no steam in exhaust) you'd pinch the hose a couple of hours afterwards and it would still be stiff. yours, however, might not be that bad. how hard is the hose when it is running? it still should be relatively pliable.
also, the cooling system on these cars was bleeding edge for the time, they operate at a pressure that is unforgiveable with respect to boyle's law/ideal gas law when a failure occurs. the "safe" area for you to stop is probably going to be around 3/4, not around the red. i think gale has a gauge to temperature picture somewhere, but the car is pretty damn hot at the point where red starts.

[EricV]

When running it felt pretty darn tight. I could squeeze it and it would give, but I'd have to give it a good squeeze. Now at the risk of sounding like a bavaria-chondriac, this afternoon it was not showing any appreciable steam/white smoke (trace, at best.) Now I must stress- lest I sound nuts- that I monitor the output of the exhaust pretty carefully, so the long time consistent steaming was new.

What you've said about it getting that near the red zone reinforces my thought that the HG (or something along those lines, warping or whatever) is what's up.

ss2115- thanks to you also. I think for peace of mind (to at least know what's up, so I can start planning) I'll go to the shop I trust an hour away and get the full physical.

[ryan roopnarine]

is it losing any water or oil?

[EricV]

It's always lost both since the day I bought it almost 8 years ago and 60K ago. :) The losses, though, have always been very consistent and minimal (both have been investigated at great length and expense, to no avail...e34's are as often as not mystery machines.)

In the 30 miles or so I've driven it since this all began the level on the expansion tank has dropped by about a half of one tick mark. Still no evidence of oil in the water or water in the oil, though I understand these things don't rear their ugly heads this early, for some, if ever.

As mentioned there's no way I'm gonna trust this thing until I get a definitive diagnosis, so I'll try to get it in the shop next week and nail this thing down so I can start strategizing the old fix it/keep it/sell it conundrum. It's a beautiful car, but if it's got something major going down it's as good as totaled (value of the car being what it is.) It's an age old dilemma...fix/keep/sell... I'm not necessarily averse to attempting the work myself, but it's more of a time/space issue (single parent, work, etc., etc. and not having a garage.)

I'll let you guys know what I learn- thanks as always.

Eric

[Tiger]

I don't think you have blown head gasket. When you bypassed the aux pump, you let air into the system. But that air is not enough to cause blown head gasket.

Refill the coolant all the way to max and let it burp.

I think you need to change your ignition cool boots. When they go bad, white smoke all the time. I did this and all smokes are gone. Same for another guy who doesn't believe me and his also gone after changing the boots.

White smokes are also raw fuel being burned by cat converter... perfect burn of gas is water and CO2. Since engine is not perfect... CO, CO2 and NOx. Raw fuel burned in cat converter is water and CO2... hence white steams... and some smell of fuel.

[EricV]

Thanks Tiger. I guess the thing that has me leaning towards it being a blown gasket or a warped head (above all of the other symptoms I'm experiencing) is the fact that it overheated. It made it right up to the red- about one needle width before the red (which, according to another poster, is way too hot.)

Now that's "as far as I know." You see, I was driving in from the country and, out there, I had to inch along (walking pace) a gravel/muddy potholed road in the rain. I don't recall looking at the needle at that time, but did not smell coolant or see steam. It was about ten minutes later- after a 10 minute 60 mph jaunt back into town from that nasty road- that I noticed the faint smell of coolant, looked down and saw the needle near the red, saw trace steam coming out of the back of the hood, and immediately pulled over to let it cool off and investigate. After it cooled (and verified I still had most of the coolant) I ran it a 1/4 mile up the hill and coasted down the other side to the shop. To get up that hill I started w/ the needle below the half mark, and by the time I crested the hill a few minutes later it was starting to approach the red again, but by then I was able to shut it down and coast.

Thanks for your tip...I did see something about that in my searches and will be looking into this also.

I am still keeping my fingers crossed that it's not a HG or something of that order, but you know the old gut feeling.

[Tiger]

If you really want to be sure, you are going to have to find a mechanic who has CO coolant detector... That is a device that detect CO in coolant. Blown head gasket will send exhaust into coolant system.

Other thing is with the radiator cap open and the engine idling... you keep hearing and feeling pressure coming out.

As for the temperature gauge... if it did not touch the red... you are still on safe side... if you are pegged in the red for extended time, then you have to start sweating... which seems like you don't.

[EricV]

Thanks again. I called the shop I use that's an hour away- again, they're the only folks I trust explicitly. They know me well and they've always been honest with me.

Anyway, he told me to bring it in first thing next Friday morning and he'll do the CO coolant detector test while I wait. He also mentioned some kind of dye thing they do. He said if it's got a head leak, they'll know for sure. So, while that's a week off, at least I'll know for sure and won't be wondering. Worth it. In the meantime my round trips are like four miles, and maybe a little more running around over this weekend (all local.) Naturally I'll be keeping a close eye on the needle, fluids, etc. until I can get it to this shop.

I'll be sure to let you guys know what they say, it's the least I can do.

[Tiger]

They got the detector that I was talking about... Just keep checking the coolant level.

[EricV]

Thanks for the confirmation. Again, I'll be sure to let you guys know, one week from today, what the verdict is. For sh*ts and giggles, if there's anything going on in the meantime, I'll let you know as well as we can all learn from what others are going through.

I've said it too many times but I'll say it again- I really appreciate this site and it's members. Great place, great people.

Have a great weekend-

Eric

[EricV]

The least I can do is provide an update for those interested or in similar situations...this is regarding the fear of the blown head gasket, the CO test, etc. after my aux pump hit the sh*tter.

I went to the shop I trust and they did the CO test- no exhaust gasses detected in my cooling system and it held pressure just fine w/ no visible leaks. They also did what they call a block test, as I was pressing on "well, where is this coolant going then?" He said that checked out fine also. So that's all encouraging.

I'm mystified on where this coolant is going though- though obviously less freaked now that it sounds as though I haven't got a blown HG. The mechanic said it could be a slow but steady seepage at some point not immediately visible (i.e. heater core or something like that far out of view) and then burning off or crusting.

I add about an inch to an inch and a half a week to the overflow tank, and only drive it about 5 miles round trip each weekday. If anyone has thoughts on this, it's appreciated.

The good news is that it doesn't sound as though I have a HG leak/warped head or a cracked block. That's a relief and my sincere thanks to you guys for holding my hand and offering sound feedback as I freaked. :)

[Tiger]

Told ya! Now what you need to do is get pressure gauge tester with the right adapter for your car and pressurize your coolant system then find the leak... it is most likely hoses. I can't tell you how many leaky hoses I found on mine.

[EricV]

You're a good man for sure, Tiger- I appreciate your patience. I sure can't see where there are any leaks, but granted I am examining things at top/normal operating pressure (not anything additional, or w/ a gauge.) Also- I am just looking at those spots/areas that I can see- it'll take a little more doing to expose or gain a visual of some other spots (esp those buried, such as heater core and some other well tucked/buried places.) For now I am enjoying the peace of mind of this morning's tests but will be sure to further investigate.

Have a good weekend everyone-

Eric

[whiskychaser]

Great news its not the head gasket! :-) The pump gland went on mine and it dripped coolant down the back of the fan pulley. You couldnt see it drip and it didnt make it to the ground. The only clue was a white deposit on the air filter box. When the penny dropped I put my fingers up the back of the pulley and could feel it damp. Maybe worth a look if only to eliminate it?

[EricV]

Absolutely worth checking, even if only to eliminate. Appreciate the idea. Now at the risk of sounding truly ignorant, what's a pump gland? I did have the pump replaced about 25K ago w/ the metal impellar pump, and metal t-stat housing. No matter I suppose as I do know the fan pulley and will give it a feel.

[Ross]

Gland is the seal.