Blown Head??? HEELLPP!!!
 

Hey Guys,

I've been having overheating problems for a long while now. Blowing coolent out of the overflow tank each trip I take. Replaced the thermostat first. I ended up replacing the radiator too just in case it was clogged or something (I had put some stop leak crap in there early on thinking that there was a leak somewhere), the water pump seemed to be working fine... hot water at both hoses leading in and out of engine, and could see coolent flow when the thermostat opened. I feel like I've done everything I can but it is still overheating badly. The overflow tank bubbling and sputtering out fluid even after relativly short trips... having to refill radiator to make it from A to B.

I got my hands on a cylinder pressure tester which I screwed into the spark plug sockets and each one filled to good pressure after turning the engine over a couple times and held the pressure without leaking. I checked my oil and it did not look milky or wierd in anyway. Coolent is green and doesnt seem to have oil in it but hard to tell.

Anyway... after about a month of this I went out there to check the water pump again seamingly the one thing i'm not sure is working right. So opened the hood took off the cap and filled it to the top. Started the car and the coolent erupted like a volcano when it started up (normal?). Needing to watch the fluid I topped it off again bubbled down, filled bubbled down, filled again till it stayed full... but It kept bubbling pretty big bubbles every few seconds but fluid did not go down. After watching this for a while waiting for the thermostat to open... i got pretty suspicious of the bubbles coming out of the radiator cap, so I got my nose down there to sniff the popping bubbles and low and behold it smelled like exhaust :(.
:wtf:
Which gets me thinking about the head gaskets again... but how can this be happening if the cylindars are keeping pressure and not leaking? It seams like the hot exhaust in the cooling system is causeing the coolent temp to rise as well as causeing there to be far too much pressure in the coolent system forcing the fluid out into the overflow tank and out even before the engine has begun to overheat. Is there a way exhaust could be getting into the coolent system other than from a cracked head or gasket?? :violin: :crying:

Just looking for some confirmation before I go tear into that project. This has been the first time I have ever worked on my own car and I'm learning a lot... but working on my heads scares me. Its not something I want to try unless I'm sure its the cause. I've already replaced so many parts that arent the problem that I feel like a total :knob:

Thanks a mill for any help you give!

wow, i have never heard of that problem.... did you check if your coolant circulating within the engine? Putting on new or used head is not that bad should take you about 5 or 6 hous by yourself if you slightly mecanically inclined... let me know how it goes.

Yeah, I would say that the fluid is circulating fine. When I have it in my garage with the cap off watching the fluid (and the bubbles) eventually when the engine heats up the thermostat opens and I see it start to gurgle and flow... the fluid level usually drops when this happens as fresh coolent is taken from the radiator into the engine. After a drive, both the top coolent hose (the one taking hot coolent from the engine into the radiator) and the bottom hose (the hose taking the cooled down fluid into the engine) are hot... meaning to me that the water pump is pumping fluid propperly in full cycles around the cooling system.

The car runs completely normally other than the overheating. Usually takes about 15 min on the freeway to overheat... and usually overheats after I exit the freeway to and from work... becuase the high speed wind is no longer helping cool what is left in the radiator by that time. I have found that the overflow tank is filling and overflowing long before the temperature guage shows signs of overheating. Uggg :barf:

Thanks for your imput Alex.

how about your fans, are they working properly?

Yes... sorry I forgot to include that info. Both fans work fine... when its hot they are on. I think one of the 2 fans is mainly or only for the air conditioner though.

I'm hoping some resident guru's here will see the post to give their 3 cents too. :wewant:

Hope to find out what exactly is wrong and then how to get it done. I'm pretty afraid of fing something up here :chicken:

whoa, ive never herd of exoust going into a radiator. are the hoses in correctly?

i would follow the hoses up to the engine and go from there. youve got a 99 protege also?
im tearing (well not tearing) out my motor, and replacing the engine intirely, maybe i could use my motor with the info you've got, and i could find the problem.. it almost sounds like something in the engine is cracked, letting exoust leak into the coolent system... im no professional at all, but thats about my best guess..

hope you can get this problem solved

Yeah the hoses are all tight... there is no coolent leak or any other leak in the engine. Its all working properly and runs great. Which is why i dont want to shoot it to hell :mach: :)

I'm just tired of fixing/replacing things that are not broken and hope to get some expert guidence on what I should do next.

First off, changing the radiator sounds like a bit of overkill for the "throw parts at it until it's fixed" method.

Since your cylinder pressures aren't leaking rapidly, I doubt it's the head gasket.

What mix of antifreeze and water do you have? Ethelene-glycol does not conduct heat as well as water. If the concentration is too high, this may contribute to the problem.

Rent/borrow the pump and attachements to pressure test the system and cap. If the system does not pressurize properly, the boiling point of the coolant mixture lowers. It sounds to me more like a pressure problem.

I replaced the radiator because it had a leak in it a longish time ago... I used stop leak on it a few months ago and was afraid that it lead to a clog in the radiator blocking free flow of coolent through it. I used some "heavy duty" flush stuff to clean out the cooling system a week ago which caused the leak to reappear :drool: (eating away the stop leak i guess). So I took the radiator out to have it repaired/rebuild... but they said it could not be repaired because of where the leak was.

I did replace the radiator cap too with one of those handy lever types. And after I drive there seams to be a lot of pressure in there. When I pull up on the leaver it bubbles and sprays coolent out of the overflowing overflow tank. My biggest concern is how fast the overflow tank begins to fill up... it begins to fill and overflow long before the car overheats... and it think that its overheating because all the coolent is getting forced out of the overflow tank by exhaust or some other gases... but I really am clueless :confused: The engine temp guage looks completely normal for 90% of the drive all while the overflow tank is spraying coolent out like mad. Only after the coolent is substantially reduced in the system (either sprayed out or in the overflowing tank) does the needle rise up to indicate the overheating engine.

Thanks GNO, I'll see if I can get my hands on a pressure tester kit. I dont think its the coolent mixture, I've been using premixed 50/50 antifreeze. What do you think about the exhaust fumes bubling out of the radiator?

Hey I don't know much about these things either, I'm here to learn from others.

I'm supposed to take it to my mechanic to hear what he has to say about my car, but so far everyone's tellin' me that I should change the thermostat.

all i can really suggest is a good mechanic.

I'm hear to learn too. I'm tired of having to depend on a mechanic every time someting goes wrong. I've never been inside a car the way I have since I've decided to do things myself and it really is a lot of fun... I never thought I would ever say that. Changed my own oil for the first couple times this months, breaks, sensors and other stuff. Love this site and the things that I learn from it. This problem has had me stumped though... but cant bring myself to give in to a mechanic unless I find out that it is a job that I can't do.

I know that there are some guru's here that haven't yet had a chance to read my problem and chime in. Just hope it gets seen.

I understand what you mean about the mechanic and it's really a nice feeling to know that you've done something on your car that you never thought you could do.

Is there no other way to get exhust in the coolent system besides a head problem?

I think it would be pretty easy for a shop to determine your problem.

1. They'll have a coolent pressure tester (attaches to radiator cap). It will detirmine if you've got a link in your coolent system.

2. They'll have a gizmo that can test your oil to see if it has coolent in it (not good).

3. They can check if your coolent is flowing. (it might be plugged up from from the stop leak)

My guess is that your engine block is plugged with stop leak. But it's just a guess.

sounds to me like air in the system. When you get pockets of air in the cooling system it'll overheat and stop circulating properly.

on the upper rad hose neck (on the engine block) is a plug that is screwed into the neck, (with the car running) CAREFULLY start to unscrew this bleeder to vent of the air pockets.once you get a steady stream of coolant coming out you'll know the air is out of the system. Try this and let me know.

I've thought about that a lot mitch. Here is why I believe that its not a plugged engine block.

1. The whole stop leak, leaky radiator problem was several months before the car had this current overheat problem. I had flushed out the coolent since then... long before this issue began.

2. When coolant isn't flowing it usually overheats much more quickly than this car is. The car doesn't overheat until enough coolant has forced its way out of the overflow tank. The overflow tank when filling and sprewing... the fluid is not that hot... it eventually gets really hot if driven long enough... but it overflows even while still cold.

3. If it is a coolent flow problem... it would overheat on the freeways just as fast as it would on the street. It wouldnt matter how cool the radiator fluid was if it was not getting into the engine properly. It is the moment I get off the freeway that it begins to overheat... because the radiator is no longer being aided by the wind to cool what is left in the radiator by that time.

It is because it is overflowing and spewing before the engine even warms up that I believe that the coolant system is being overpressurized by some outside influence... which is forcing cool fluid out of the overflow tank.

I feel like I want to recheck the head pressure again more closely... but I had just changed the oil on the car with mobil 1 just a few days before I did the pressure check. When doing the pressure check you dump unburnt fuel into the oil (you have the plugs pulled) which ruins the oil. So I had to change the oil again after the pressure test I did. I think I'll barf :barf: If I have to pressure test again and ruin the brand new mobile 1 extended I just put in. 3 changes in a couple weeks I can't afford that :(

This sucks.

I had a Chevy Luv pickup with a 327 Covette engine in it (fun ride!). I constantly had over heating probelms with it, very similar to what you describe. I even replaced the radiator with an expensive 4-core radiator. I accidently cracked the crank shaft because I lugged the engine too much going over a small curb. Anyway, I sold it with the engine broken. When the guy tore it down he fixed the crank, but he also found what looked like big pieces of gravel at the input port of the water pump. He flushed them out (they were big!) and the engine never had over heating problems again. I had a mechanic look at the "gravel" and he said it was Stop Leak.

Maybe remove the water pump and have the block flushed? Its not that expensive (you might be able to do it yourself with a garden hose. Although higher pressure would obviously be better.

Also, try having the oil checked (or maybe it's the coolent) to see if one has gotten into the other. That's always a tell tail sign of a blown head gasket.

But you're right....this has got to be VERY frustrating for you.

so that's where the thermostat is!
I have seen this in illustrated diagrams before, but it's much more clearer when you see a pic of it like this.

I agree. if it was the head there would be tan colored floties in the radiator caused by the oil and coolant mixing.

Those pics did not show a very good angle I dont think and I was pretty dirty in there. I just sprayed degreaser all over and power washed the engine and took some more shots. Can someone point out where the bleeder valve is? Am I looking at the right thing?

http://members.cox.net/adder/bleeder.jpg

New clean engine :) Yum!

http://members.cox.net/adder/overview.jpg


I let the car idle for about an hour in the driveway while taking these shots.

As I've said the bubbles start flowing into the overflow tank almost immediatly after starting the car cold and the overflow tank slowly rises, this video clip shoes the bubbles after about a half hour. I started the car with a full radiator and an empty overflow tank... as you can see in the vid that its almost up to the full line buy that time.

Bubbly Overflow Tank Video

Took a flyover video of the whole engine, you can hear the radiator fan kick in seconds after this second video starts.

Engine Overview Video

Let me know what you think!

very clean engine....

my sh** is unbelievebly dirty. and its the same engine!

Thanks :).

Can someone have a look at my last post and let me know where the bleeder is that Rodimus Prime is talking about?

sounds to me like that radiator is plugged up and not flowing properly.Also have you had that system pressure tested???. It can still cool on the highway becasue you still have all that air rushing over the rad AND the engine itself...I just looked to and you used STOP LEAK and coolant instead of water ???? BAD combo...those stop leaks are supposed to be run with water only, not antifreeze

Read some more of the thread Mac, I have a brand new radiator in there. The stopleak thing was a long time ago, and I did not use it with antifreeze, and only used 1/3 of the contents of the bottle. Months after the stop leak was used I had none of these problems I have today. And flushed the cooling system withing the same week that I did the stopleak. I'm hoping to get some feedback about the exhaust fumes I'm smelling bubling out of the radiator/overflow tank. Am also hoping someone can tell me where the bleeder is that Roddimus is talking about... see previous posts in this thread.

Sheesh.... the more I work on this the more I worry about the VERY strong smell that is comming out of the boiling over overflow tank. It smells very strongly of raw fuel or exaust. I had a couple people come smell it and it is DEFINATLY not a normal/good smell. I've smelled boiling over cars many times and this is not the smell. I went ahead and pressure tested all of the heads one more time and again... no leaking pressure. The test I'm talking about involves taking out a spark plug and screwing in a tube hooked to a pressure guage. You then turn the engine over a few times with the starter to pressureize the chamber. Pressure did not drop on any of the cylindars. But exhaust or some other foreign gass is getting into the coolent system somehow, and causing the air bubble symptoms that Roddimus is talking about. I could not find a bleeder valve on this model by the way. Could there be a crack in one of the exhaust ports in the engine that allow exhaust gasses to flow into the coolent system that would cause these issues I've been having? Macdaddy.... I got the coolent system pressure tested and it tested OK. The radiator cap is new... and definatly holds the pressure in there. Its the lever type... and it only lets stuff get into the overflow tank when the pressure goes over its max setting. At any time while running the car if I pull up on the cap lever a huge blast of gasses escapes into the overflow tank. Help!!

picture
 

bleeder is also the stock CTS (coolant temp sensor)

Thanks Roddimus.
Here's how it went down this morning.

I went out to the garage and unplugged the sensor so that I could loosen it when the time came. Got in the car to start it and it wouldnt... just turned over and over (guess the sensor needs to be connected for the car to run). But what I noticed when I was turning it over to start it was that the overflow tank was bubbling... this is on a totally cold engine. So just to test that more I didnt plug the CTS back in for a bit and turned the car over some more just holding the starter on, and HUGE bubbles started to garble up like crazy out of the over flow tank, much more so than when the car is running on its own. So there's a bit of a clue for ya, doesn't sound too good does it. There is defintaly not a blown/cracked head gasket like I first thought... although everything seams to scream thats the problem.

Anyway Roddimus, I plugged the CTS wires back in and the car started up, pulled the wire and it died. Plugged the wire in and started the car again, and this time used a open wrench to loosten the CTS, till fluid/gases started coming out. The gasses never stopped. It never became a pure coolent stream. Kept adding coolent during the test to keep the engine from overheating. The gas bubbles never stopped after about 8 min of this and coolent runnining down my driveway and down the street gutter. So I tightened the CTS back in.

Couple other notes:

Reading info in other places I did the following.

To test coolant circulation I tested the heater which works perfectly... the heater will not work properly if coolent is not circulating, it will blow cold.

To test if exhaust is in the coolant (if exhaust is in the coolant, coolant will be in the exhaust) so I went to the back of the car and checked the exhaust pipe.... which had a continual light flow of white suds (like soapy water) coming down the pipe non stop for so far a half hour (still running out in the garage). :tear:

Click here to download 3mb exhaust video.

Not lookin good is it.... what advice do you have?

I couldn't look at the video, but the only puzzle piece that doesn't fit is the good compression readings. Check the compression with the the cooling system empty, with caps off and drain cocks open.

Bubbly cold water with enough pressure to get past the pressure cap,
smokey exhaust bubbles in the water,
foamy effluent in the tailpipe... I just can't see anything else it could be but the head.

I'm thinking head too..sounds BAD

What about a crack somewhere outside the cylindar, between an exhaust port and a coolant port? I tested the pressure in the heads pretty extensivly especially the second most recent time. I left the pressure guage on each head for at least 10 min at full pressure and they did not drop in the slightest bit. The cylindar compression was well within the appropriate range for each head... even toward upper range. Had the cap off the radiator during the cylindar pressure tests. Does a crack in an exhaust port make any sense? I have to make damn sure its a head before I do all that work. I think I'll slit my wrists if I do the heads and be in the same boat when I'm done (or worse becuase I screwed up the job). Thanks you guys for the last few posts! I think we are finnally getting pretty close to the problem. I will do the pressure tests again if you really feel I should. I wish I could somehow capture the bubble smell for you guys to have a wiff at. I just cant afford a smell-o-scope right now. ;)

YOU HAVE A CRACKED HEAD. Yup. No doubt about it.

The exhaust smell at the radiator cap confirms it. Under intense pressure when the engine is firing the crack passes exhaust gas. The cylinder pressure testor doesn't reach the gas pressure and temp of an IC engine.

Pull the head and have it Non-Destructive Inpsected (NDI'd) at a machine shop.

-sorry to hear about it.-

if you need more exact details why i believe it is a cracked head - let me know! I have walked this road before.... sigh.

I'm with P-funk , pull the head. I've hed the exact same symptoms on a car and buddies old Toyota mini van does this. An engine will run with a cracked head or bad head gasket drawing water into the cylinder and the only sign being the system lossing coolant and then overheating. On an old accord I had the car started and ran on 3 cylinders for a couple of minutes then was fine....two days later your symptoms showed up.

Pull the head and you will find the source of your water loss. Oh and unless you are stranded miles from nowhere in a clunker car , never use stop leak it causes as many problems as it solves.

Tom

Thanks P-Funk, I would love to hear every detail you have to say... I've been stressing over this for a while now. It would be nice to know what you know about it. It would help a lot to have the same confidence you have in the problem cause, and I'm trying to learn as much about the car/problem as I possibly can.

If I do go ahead with what you are saying. Where can I get detailed information about how to pull the head properly? How much can I expect to have it tested. How is it repaired/replaced. Could you estimate the time and cost to get the job done?

With all the money and time spent to replace/repair the head..It would be cheaper to replace the whole engine...ZM-DE's can be had for like $300-$500

As long as everyone is confident that its a cracked head and that replacing the engine is the way to go... how/where do I go shopping. Spent a few minutes just now looking around and found horrible looking engines sitting in dirt and covered with rust selling for ~ $500... *shrug* :dunno:

That is sickening news though. The car really does runs great... while the coolant lasts that is. Bleh!

here is what to do: you can't keep driving it this way.Get a manual and take the head off. After inspection you will be able to determine your cost. For a shop to do this I would think it would be between $600-1200 depending on the severity of the damage.

The used engine thing is an exceptable alternative....I raced my Miata with a used engine , wasn't a problem and it was sitting in the dirt like the ones you saw.

You really can't make an informed decision until you know the extent of the damage. So get the cyclinder head off and then decide.

Tom

check car-part.com

I have the Haynes Manual... but its a joke. It tries to cover 10 years of models... the 323's and Proteges... its nothing looks really the same, or is too general.

Macdaddy... any of the 1999 1.6L AT engines listed there are good. Will 2000's work... which should I focus on?

im pretty sure the set-ups are basicly the same for 99's and 2000's

but it might be easier for a 99