I think head gasket but symptoms don't support theory

[akafriday]

98 Subaru 2.5L Outback 284k KM

 

Now I know everyone will say head gasket but please keep this in mind before reading on:

- Mechanic tested head gasket using chemical that tests for combustion gases in coolant and test was ok.

- There is no coolant in the oil - checked via dipstick

- There is no oil in the coolant - checked in resovoir

- There are no visible coolant leaks

- There is no indication of coolant being burned and steam coming out the tail pipe.

- The heat in the vehicle is perfect.

- There are no strange smells.

 

Initially the temperature spiked I immediately pulled over let it cool off and returned home which luckily was less than 3 minutes away.

 

The thermostat, and hoses were replaced with a non-OEM and temperature spiked again. The thermostat was then replaced with OEM and I drove for almost 2 weeks without trouble until today.

 

The temperature spiked again - I pulled over and waited, checked coolant in rad - topped it up (very little) and continued on and had no trouble.

 

I have noticed bubbles in my coolant resovoir and a hissing like air either being pushed out or sucked in not sure which. The hissing is coming from the vicinity of the rad cap. In an attempt to address this I replaced the rad cap but the hissing and bubbles persist. The bubbles appear immediately after driving and gradually disappear suggesting coolant system is sucking air from somewhere.

 

Not sure where to go from here - based on the absence of symptoms supporting head gasket failure I am not sure what else it could be. I would appreciate any advice people could offer.

 

Thanks in advance.

[akafriday]

Thanks Nipper. Is it worth it to fix it? I seen quotes for almost 2k... http://www.ultimatesubaru.org/forum/images/smilies/frown.gif

 

Is there any magic additive worth trying????

 

This sucks.

 

Thanks for the reply.

[Quidam]

Hi,

 

Without reading the replies, put a vacume gage on the motor. Report what it reads.

 

Doug

 

Edit. I would take a very close look at the radiator as well. Pull it out, strip it down, flush it out.

 

I'd want that vacume number.

 

Edit: If it has good vacume, it has good compression. If it has good compression, it has good vacume.

Edited November 13, 2008 by Quidam

[Rooster2]

The Gen 1, 2.5 motor blows head gaskets by allowing exhaust gas to enter the cooling system. So, you won't see any fluid leaks anywhere, or coolant in the oil. The bubbles in the over flow is a dead give away of HG trouble. The bubbles you are seeing is exhaust gas.

 

Unfortunately, there is no magic additive to stop the force of the exhaust gas. Replacing the head gaskets is the only way to repair the problem. As mentioned, a new radiator cap may help some, but I don't know the logic behind doing this. Keep us posted on your course of action.

[Quidam]

Hi,

 

Without reading the replies, put a vacume gage on the motor. Report what it reads.

 

Doug

 

Edit. I would take a very close look at the radiator as well. Pull it out, strip it down, flush it out.

 

I'd want that vacume number.

 

Edit: If it has good vacume, it has good compression. If it has good compression, it has good vacume.

 

Bump.

[msmithmmx]

1

[msmithmmx]

If you could not find any hydo-carbins in the coolant, I would say that your compression test is going to show normal. I would try the blue bottle (coolant conditioner) from the dealer. With your miles you have lucked out for this long. Hard call about fixing, if you could do yourself I would say go for it. You have a slow HG leak.

[GeneralDisorder]

Do it yourself for a couple hundred. Learn something. Be self sufficient. Etc.

 

Or drop in a used 2.2L instead. They didn't suffer from these problems.

 

GD

[akafriday]

Thanks all for the replies.

 

I already replaced the rad cap - damn bubbles are still there.

 

Going to try a cooling system additive that stops leaks. I know, I know there is no reason to think this is going to work but what the hell.

 

As far as doing it myself.... well it is our only car and my wife would kill me if I had it apart for a number of days.

 

I tinker but I have no illusions regarding the complexity of this job. I am 100% positive, being a first timer, I would miss something be it not torquing something to spec etc. that would leave me doing it all over again.

 

Out of curiosity - is it possible to replace head gaskets without removing the engine?

Edited November 14, 2008 by akafriday

[davebugs]

It's your car - and I understand your thinking.

 

But a stop leak product is gonna do more to stuff up your heater core and radiator than solve your problem. It's likely to add things to your 'issues' list and the original problem will still be there.

 

If you like the car and think it's worth hanging on to just bite the bullet and get it done correctly the first time. Along with timing belt, spark plugs, reseal baffle plate, check cam/crank seals, idlers, perhaps water pump, etc. then you're probably good for the next 100k (except perhaps for the plugs).

 

Dave

[akafriday]

Thanks - dave,

 

I was considering that - but I know that the transmission was slipping as well after a fluid change. It was drained and filled with synthetic and I added a Lucas stop slip additive and it has been fine so far, however, I know that there are trany problems there as well so in addition to the possible HG failure - at this point I am not sure it is worth the investment.

[davebugs]

I'd probably get another one then. Now you know what to look for, take a long test drive, etc.

 

Bummer.

[subsince77]

Take it from someone who has been there, you are almost certainly experiencing the beginning of the 2.5 HG problem. It comes and goes. I found that I could run my car locally with no problems because I live in a small town where I don't have to get up to highway speeds to get back and forth to work etc. But the car would start to overheat as soon as I took it above 50 or 55 mph. Once the overheating began, I would have to shut her down until it cooled completely. I was able to limp along like this for several months as I did the thermostat, rad. cap, new radiator dance. You always hope.

 

I opted to get a rebuilt engine, but my car and transmission were in great shape. Let me emphasize that I NEVER let the temp get near the top of the gauge. You will just have to assess the cost of repairs verses life left in the car and make a choice. If you have severely overheated the car already, that's a big problem. One good thing is that, given a good engine that has not overheated, problems with the updated HG that would replace your old one are said to be rare or non-existent.

 

Best of luck

[screwbaru2]

I've had good luck with Alumseal. I've got a 96 OBW w/ 90k 2.5 known bad HG was starting to over heat. Put a dose of alumseal in 2 months ago no problem since then. Worked for a year in my 97 OBW w/180K drove that car 100 miles a day. I'd try alumseal and use the time to find a good 2.2 to replace it.

[Dickensheets]

I had this problem in June. Same symptoms. I replaced the the gaskets with OEM and had the heads checked/cleaned by a machine shop. Yes the engine has to come out but I have 2 cars so......

 

I spent a total of about $500 with parts and shop time. It's November now and 7500 miles later. I figure even if it blows tomorrow it was cheaper than a car payment. The rest of my car is solid so that played into my decision to fix it.

 

97 OBW 135,000 miles to date.

[simbey1982]

I would vote for headgasket failure...or worse than that a cracked head but thats pretty rare...if you have the tools and some subaru familiarity its not that hard to do

 

Good luck

[McDave]

Thanks all for the replies.

 

I already replaced the rad cap - damn bubbles are still there.

 

Going to try a cooling system additive that stops leaks. I know, I know there is no reason to think this is going to work but what the hell.

 

As far as doing it myself.... well it is our only car and my wife would kill me if I had it apart for a number of days.

 

I tinker but I have no illusions regarding the complexity of this job. I am 100% positive, being a first timer, I would miss something be it not torquing something to spec etc. that would leave me doing it all over again.

 

Out of curiosity - is it possible to replace head gaskets without removing the engine?

 

I'm going to take you at your word as a first timer and tinker-er and recommend you not attempt to do this job yourself, unless you buy a second car first so you can take the time to do the job right the first time. Even if everything goes like clockwork the car will likely be down for a minimum of 2 weeks, particularly if a machine shop reworks the heads (you should have that done too with that many miles).

 

It would probably be easier and cheaper for you to drop a 2.2 in it like GD suggested. It still might take you a week or so though, unless you have vacation time coming.

 

Bottom line - Since you have to keep your family rolling, start looking for a cheap second car now and fix this one later. It's either that or rent a car while a shop fixes this one, imo.

 

In the meantime, there is nothing wrong with modern stop leaks like Alumaseal or Subaru's sealant. They won't stop up your system when used as directed, but they may not be much help with a head gasket already leaking either, though Bars-Leak now makes one for head gaskets that looks interesting.

Edited November 19, 2008 by McDave

[idosubaru]

don't keep this engine. if it's your only ride and you've been driving it like this, then it's almost certainly been overheated and cycled too many times for me to want to keep it for any length of time. the Phase I EJ25's just plain overheat, so if you're continuing to drive it it's probably not in great shape.

 

that being said it's usually not hard to get a couple hundred dollars for a used EJ25, so if you do replace the engine keep in mind this one is worth something. since they have issues they are worth something even in poor shape. half the time if it's at least running and just needs gaskets you can get enough out of it to pay for a new EJ22 to swap in.