Over heating problem, 98' Forester

[tahoecush]

1998 Subaru Forester, problem with cooling system, Vehicle has been serviced by Mincemeat (not the real name) twice for the problem. Original problem was the cooling system would loose its fluid when the car had to climb a mountain. An elevation increase of 1500 feet or so would tax the engine enough to cause the radiator fluid to blow off and the temp gauge to read in the red. This leak would occur in the engine compartment and not into the radiator overflow reservoir. I took the car to Mincemeat and had it serviced. They replaced the thermostat and the radiator cap with one marked “Made in China”. They also flushed the radiator and performed a pressure test. The car did OK until it had to go up hill on its way home, across the summit of Mt Rose it blew off the fluid from the radiator as before. The engine compartment filled with steamy smoke that smelled of radiator fluid, but the source of the leak was not detectable. A week or so later when my daughter returned with the car I added at little over ½ gal of fluid to the radiator and let the engine run for about 10 min or maybe longer to get the temperature up. I noticed some fluid spilling on the ground and traced it back to the radiator cap. I then drove the car back to Mincemeat to have it looked at again. This time I insisted he use a quality radiator cap and he assured me he had installed one “made in the USA”. They also charged me again for servicing the radiator but not for the replacement cap. I drove the car back up the mountain myself and I had no problem whatsoever with the car. About a week later I talk with my daughter and she said the car had overheated again, and she thinks it blew off the radiator fluid. A few days later when she had the car at my house I added about ½ gal of fluid to the system again to top it off. The overflow reservoir was empty so I don’t thing the fluid expanded into the reservoir as it should have.

 

Is a Genuine Subaru radiator cap in order here? Anybody have any experience with a similar problem? Other than this problem the vehicle is very reliable, especially the AWD in the snow and ice.

[tunered]

if the spring in the radiator cap was weak it would let the fluid go into the recovery tank,if it was to stiff it would blow out at the weakest point. there has to be some indication of where it came from,antifreeze is oily,and does not dissapear fast.you will have to locate this leak.i really dought if it is coming out of the rad cap,look for hoses that may be loose,weak,or possibly have a pin hole in it.

[nipper]

1998 Subaru Forester, problem with cooling system, Vehicle has been serviced by Mincemeat (not the real name) twice for the problem. Original problem was the cooling system would loose its fluid when the car had to climb a mountain. An elevation increase of 1500 feet or so would tax the engine enough to cause the radiator fluid to blow off and the temp gauge to read in the red. This leak would occur in the engine compartment and not into the radiator overflow reservoir. I took the car to Mincemeat and had it serviced. They replaced the thermostat and the radiator cap with one marked “Made in China”. They also flushed the radiator and performed a pressure test. The car did OK until it had to go up hill on its way home, across the summit of Mt Rose it blew off the fluid from the radiator as before. The engine compartment filled with steamy smoke that smelled of radiator fluid, but the source of the leak was not detectable. A week or so later when my daughter returned with the car I added at little over ½ gal of fluid to the radiator and let the engine run for about 10 min or maybe longer to get the temperature up. I noticed some fluid spilling on the ground and traced it back to the radiator cap. I then drove the car back to Mincemeat to have it looked at again. This time I insisted he use a quality radiator cap and he assured me he had installed one “made in the USA”. They also charged me again for servicing the radiator but not for the replacement cap. I drove the car back up the mountain myself and I had no problem whatsoever with the car. About a week later I talk with my daughter and she said the car had overheated again, and she thinks it blew off the radiator fluid. A few days later when she had the car at my house I added about ½ gal of fluid to the system again to top it off. The overflow reservoir was empty so I don’t thing the fluid expanded into the reservoir as it should have.

 

Is a Genuine Subaru radiator cap in order here? Anybody have any experience with a similar problem? Other than this problem the vehicle is very reliable, especially the AWD in the snow and ice.

 

Are your electric cooling fans coming on? and yes i would ditch thre cheap raditaor cap, go to an autoparts store and get a STANT cap

 

merry christmas

 

nipper

[1 Lucky Texan]

I dunno why the o'flow tank is dry, unless as mentioned the leak is other than a bad cap - but have you considered you may have a stuck or partly stuck thermostat? Here especially, I've read you DO NOT want an aftermarket part. Subaru thermostats only please.

 

Also, it may be worth checking the spark plugs. If one looks distinctly different from the others, you might be blowing the coolant out the tail pipe.

[tahoecush]

Thanks for response ya'll.

 

Update, as of 12/25/05 my daughter reports the problem has not reoccurred.

 

I feel sure this was caused by a bad rad cap and then exacerbated by a cheep aftermarket cap. I did see leakage at the new cheep cap as I stated before, then had a new cap put on that did leak once but now seems to be holding.

 

Nipper, a STANT cap sounds like good advise. Do you think that would be better than one from the dealer?

 

The exaust is clear so I don't think the coolant is getting into the engine.

 

Tex, I believe the overflow tank was dry because when the engine cooled after the coolant leaked around the top cap seal, all the coolent in the overflow reserviour was asperated back into the radiator. Since the radiator was now below it's normal level no fluid was pushed back into the reserviour when the engine warmed up again.

 

A new STANT cap is on my shopping list. Thanks again all.

[cookie]

At this point if it were my car it would get head gaskets. With the daughter driving it in challenging conditions that would influence my choice.

I would also look at the radiator, and check the fans and water pump.

A good quality cap would be a good idea too but these engines have quite a rep for head gaskets that start very slowly.

[sea#3]

I'm with Cookie

It's the start of a head gasket problem . You can do coolant pressure tests , you can try checking for bubbles in the over flow when running ,you can check for CO ( carbon monoxide ) coming from out of the rad using a dye or a gas bench

But the best way i have usually diagnosed this problem is by doing a leak down test on each cylinder with the rad cap of and the rad topped up to the brim of the neck and watch for any change in the level

 

SEA#3

[Sweet82]

I had some mysterious heating problems last fall.

Seemed to occur mostly on hills or the flat after a hill.

 

I'm now convinced it was a bubble in my cooling system.

 

Improper filling of the cooling system can generate strange temp behavior.

 

Not sure this is your problem but, since you've been messing with the system, I'd make sure your coolant is correctly filled.

 

Good Luck,

Glenn

82 SubaruHummer

84 GL Mad Max

01 Forester

[tahoecush]

Update to my original post.

 

Took the car to Tom Tuhey’s Auto & Truck in Kings Beach, CA. He specializes in Smog & Repairs, and computer diagnostics.

 

He reset the computer so the [check engine] light would be reset. He showed me the diagnostic screen that displays the different codes and whether they have reset or not. Four of the codes will not reset until the car has been cycled on and off a certain number of times etc.

 

The car passed all tests except one. When a gas sensor was placed into the overflow bottle it indicated that hydrocarbon gasses where found in the cooling system. This indicates a HEAD GASKET leak from the exhaust side of the head.

 

From all the threads I’ve read in this forum it seems I hit upon the most common problem with the 2.5L engine.

 

I’ll post again when I decide what to do next.