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overheats going down hill?????


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O.K. I got one for ya'll

 

So you think you need a Headgasket? Consider replacing you're radiator first if it has over 200k on it. Here's the example why.

 

91 Legacy AWD, 2.2, Manual.

New water pump, OEM Thermostat, working temp sensors.

Car runs great. But pushes water out the overflow slightly. HG right? Wrong.

 

It never overheats (or really loses any water) on level ground or going up hill, no matter how hard you flog. The water being pushed out is cold?????? And when you go down hill for any length of time, it builds a bubble in the engine, and overheats big time.

 

When it overheats, if you crack the fill vent on the left(standing in front looking at the car) it blows out steam, hot boiled steam. But on the right, the rad cap is completely cold, the water in the overflow is cold, 90% of the radiator is stone cold.

 

Plugged radiator. Not enough water gets to the thermostat, which is "downstream" of the radiator on an EJ. This and the low flow of the radiator causes the water to overpresurize and start boiling and steaming inside the block. On flat ground, the steam rises to the top of the radiator. But going down hill, the pump cannot force the steam to go "down" into the radiator. Al the water flows down, and the steam builds inside the block.

 

I wonder how many people have changed headgaskets just cause they had overflow and a few overheats, when all they needed was a radiator?

 

(note, HGs do go bad too. Always diagnos thoroughly before starting a job)

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Not too many since when most replace thier head gaskets it cures the problem. Also with a clogged radiator you would pass the bubble and exhaust gas test.

 

Another thing people need to do is physically inspect the radiator. The engine side may look fine, but the ac condenser side may have lost all its fins. They need to physically unbolt the radiator and push it bac, then inspect it with a flashlight.

 

This is especially true if the vehical is over 12 years old.

 

nipper

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First off you are talking about a 2.2L. They don't have the head gasket problems of the 2.5L DOHC engine.

So in my mind, head gaskets are usually one of the last things on the list of things to check, when diagnoising 2.2L over heating problems.

 

EJ22 vs. EJ25 = Different animals. Diagnoisis can / should be approced differently.

 

How many radiators do you think have been replaced trying to fix over heating problems with 2.5L DOHC engines that had bad head gaskets.:)

 

You have to consider: Engine type. All symptoms. When / under what circmustances they occur. With everything in mind, you can start with most likly cause first.

 

Pattern failures are real.

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I got my '97 OBW with a '95 2.2 swap cheap because of this.

 

I bought it off the back off the used car lot (never bought one off the front line, and I never will... salesmen hate me :) ). Owner of the garage/sales lot said that it was overheating, that they swapped out one HG, amongst other parts. His offer was $3,000 for the car, a $1,000 to swap in a EJ25.

 

Sold. (~125Km on the ticker, two spots of rust the size of my pinky, in NY state. Duh.).

 

So he swapped in the 2.5, and I brought it back a week later for overheating. He couldn't replicate it. Same thing a week later... and this continued. He extended the warranty. Finally brought it in while it was overheating... and they couldn't figure it out. It stopped, they handed it back to me, and continued to verbally extend the warranty. Throughout, he stated several times that they "checked out the radiator".

 

Finally, I toasted the engine. Big black smoke, rough running, CEL blinking. Bad mojo. Drove it back to the lot, and it sat for a month while the owner of the place tried to find a replacement 2.5 (cheap, I imagine... he stated that he had problems finding someone who would sell a Phase 1 2.5L without rebuilding the heads & updating the HG's).

 

I mentioned the '95 2.2L swap, which was something that I had been considering doing myself down the road. His eyes lit up... called some reference, who assured him that the swap would work. A week later I pick it up.

 

And it overheats driving it home. So I pulled the radiator, flipped it upside down, and chunks of what I assume are various minerals fall out. Checked the radiator my arse.

 

Anyway, a $150 radiator later, and I've got the engine swap I wanted, with a wonderfully almost-rust-free chassis, for a great price. Sometimes you just gotta get lucky.

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Not many, maybe one but you caught it. The 2.5 is the problem not the 2.2.

 

Not sure what you mean buy "Not many, maybe one". Radiators? Per car? Sure.

 

Out of all the 2.5 engines in the country that over heat do to bad head gaskets, and are miss diagnoised................I personaly have seen more than one 2.5 with a new radiator and/or (thermostat, W/P, rad. cap, ect.) still over heating due to head gaskets leaking.

 

Anyhoo.............Yes, radiators do plug up. And as nipper pointed out, not always internaly. I have hosed mud, dirt, and bugs out of the cooling fins of many a radiator and or condesor, to fix "running hot" problems.

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O.K. I got one for ya'll

 

So you think you need a Headgasket? Consider replacing you're radiator first if it has over 200k on it. Here's the example why.

 

91 Legacy AWD, 2.2, Manual.

New water pump, OEM Thermostat, working temp sensors.

Car runs great. But pushes water out the overflow slightly. HG right? Wrong.

 

It never overheats (or really loses any water) on level ground or going up hill, no matter how hard you flog. The water being pushed out is cold?????? And when you go down hill for any length of time, it builds a bubble in the engine, and overheats big time.

 

When it overheats, if you crack the fill vent on the left(standing in front looking at the car) it blows out steam, hot boiled steam. But on the right, the rad cap is completely cold, the water in the overflow is cold, 90% of the radiator is stone cold.

 

Plugged radiator. Not enough water gets to the thermostat, which is "downstream" of the radiator on an EJ. This and the low flow of the radiator causes the water to overpresurize and start boiling and steaming inside the block. On flat ground, the steam rises to the top of the radiator. But going down hill, the pump cannot force the steam to go "down" into the radiator. Al the water flows down, and the steam builds inside the block.

 

I wonder how many people have changed headgaskets just cause they had overflow and a few overheats, when all they needed was a radiator?

 

(note, HGs do go bad too. Always diagnos thoroughly before starting a job)

O K everything said in this post happens to my 90 leg, but I will add that this only happens to it in the summer AFTER climbing to the top of some mountain at high load low speed lots of 1st gear logging road stuff. I make it a habit of checking coolant level before going down, if the level is high in expansion tank I pop the cap siphon the exess into a jug and pour it back into rad, go down hill with no problems. Radiator is just 1 year old. It does blow bubbles almost anytime I check but never really has a problem of overheating. I do suspect headgasket weakness but for the little bit of trouble I get from it I'll wait till its worse, or I just get really bored, been this way for 70,000 miles.:horse:

g

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