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overheating mystery


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My final guess as to the cause: you are running a 1600cc engine in a car whose weight and drag characteristics, requires an 1800cc engine or better. You bought the car from someone else who was likely dissatisfied with it. Perhaps now you know why he dumped it. I know that everything has to be working perfectly, for my 1800cc w/ turbo w/ double core radiator, not to get real hot in the summer time. And I don't even drive fast.

Edited by scoobiedubie
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Well......if the fans runs OK, and thermostat is OK, radiator is OK, Hoses are Ok......water Pump Ok......let me know if you check the coolant level. It is always at the same level? There are two bypass pipes in EA81, one over #2/4 head cylinder and the other in the back of the intake manifold. Have you check leaking there? Because when it leaks coolant from that pipes, it's goes directly to the hot engine, evaporates and it's difficult to see that, but you can smell it.

 

Have you check that?

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The bypass hoses are the same as on the EA82. I replaced the one behind the intake manifold gasket, and the one that is the bypass for the thermostat. I also replaced the water pump --> heater core hose. Both rad hoses are new within the last year. The radiator is off the shelf new to the best of my knowledge (or so refurbished it may as well be). Water flow in the radiator was so good as to be scary when I flushed it during the flush/fill I just did.

 

After the last spike-red and boilover, I refilled the radiator once it was cool to the touch. Even with the boilover I added under a quart of water, and most days it's nothing or a cup or two, and I know I lose some regularly to sloshing out of the overflow/evaporation/etc. Due to not having a cap on the overflow tank.

As for longevity, I have had this car for four years now, going into the fifth, and the EA81 motor was put in just last summer. I thought it was a 1.8 carbed engine (with the injected manifold mated on instead of the carbed one), though it could be the 1.6. My horsepower is not noticeably reduced, and the torque only slightly so. Heat has not been a problem until now, and I have run it on hotter days in worse traffic/sun (harsher conditions) than I was/have been in more recently with much less trouble. It is a new problem. It could certainly be the thermostat, though the upper radiator hose gets hot, and there is sufficient flow into the overflow tank to make me think the 'stat is open, though it could be only partially opening and/or the bypass is pushing a significant volume of water. I was going to pull it today and try driving without it, but got called into work on my day off. I am scheduled off again tomorrow, so will make another go at it.

If this fails to fix it I think I'm going to make an appointment to have it seen--I need the car for work desperately, as we often receive calls that I have to respond to all over town, making the bus impractical. Running warm I can tolerate, but this latest episode AFTER all the work I've done is unacceptable. It spiked into the red over the course of a few lights and I had to pull over to let it cool down. That is not ok--just glad I had finished the call and wasn't on my way TO a job.

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Is your thermostat an OEM one?

Is your heater core flowing properly?

Do you have a hose suctioning itself shut upon heavy throttle?

What color is your antifreeze staying and what kind of antifreeze are you running in it?

And did all the trouble start before or after you lost your overflow cap?

 

Twitch

 

PS: Scoobiedubie, the EA81 and EA82 are both 1.8L engines, the EA71 is the 1.6L. The EA82 is the overhead cam version of the EA81 (in layman's terms).

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The coolant is staying bright green now that I've cycled it and drained/refilled.

As of this afternoon I have no thermostat, I'm going to see if that makes a difference. If it does, I'll know, if not, I'll run to the shop and have someone take a look at it.

 

The trouble didn't 'start' after I lost the cap, but it did increase notably. I'm not sure if the messing around I was doing did something funky to the motor or the cap loss did it. It doesn't SEEM like it would, but I don't know.

Good thought on the hose closing up. As far as I know, no, but I haven't put the pedal down and stood to look at the motor. All new hoses, and re-enforced.

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My final guess as to the cause: you are running a 1600cc engine in a car whose weight and drag characteristics, requires an 1800cc engine or better. You bought the car from someone else who was likely dissatisfied with it. Perhaps now you know why he dumped it. I know that everything has to be working perfectly, for my 1800cc w/ turbo w/ double core radiator, not to get real hot in the summer time. And I don't even drive fast.

 

EA81 engine is still a 1.8 displacement engine.  Shares excact bore and stroke with EA82.  That's not the cause.

 

And if he got the car from ShawnW, you can bet it was tip top, and not some "disatisfying" car that he was trying to dump.

 

Your car get's hot because it's an EA82 turbo, which probably has cracked heads and burns coolant and even if it doesn't now it will soon.

 

And as an FYI, loyale body cars did come with EA71 engines (1.6) in other parts of the world.  Like Isreal, in the desert. So even if he did have a 1.6 in there, it would still be within the realm of driveable without overheating easily.

 

To the OP in this thread, I hate to say but you should think about doing headgaskets.  If it's filling the overflow and pushing out coolant, then it needs the headgaskets done.  Good news is EA81 headgaskets are super simple.  Like stupid simple.

Edited by Gloyale
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I've changed the radiator cap a few steps ago. Will watch over the next few days now that I've pulled out the 'stat and see how things go.

I assume if I'm still overheating after pulling the 'stat I have some big problems. And it's NO THERMOSTAT, not 'new-may-fail-out-of-the-box' until I've sorted this mess out.

I'd hate to do head gaskets, first time on an EA81 though, and it looks SO MUCH SIMPLER than on the EA82. We will see, I guess?

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I had a heating problem on my first Loyale and it was partly due to a knock-off thermostat and partly due (I think) to the fan shroud having been cut for ease of assembly. The fan shroud is there to keep up the fan efficiency by not letting air spill around the fan sideways. That shroud is in the way, and lots of people cut them so only the top 1/4 is on. There's a loss of cooling efficiency right there. The OEM thermostat has a long piece that assures it is sensing the coolant, and not an air bubble up there. If you have an air bubble, it will not conduct the heat to the bimetalic strip and not open it up when it should. Knock-off thermostats are shorter and sometimes, a bubble will fake it out.

 

Also, are you sure your temp gauge is correct? It might be a bad sending unit that is falsly reporting a high temp. It's a few dollars. I'd just change it. Also, use a cheap infrared thermometer to measure the temp at the thermostat and see if it is what you expect, and if it diverges from the gauge in the dash.

 

Good luck.

cnc

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I've changed the radiator cap a few steps ago. Will watch over the next few days now that I've pulled out the 'stat and see how things go.

I assume if I'm still overheating after pulling the 'stat I have some big problems. And it's NO THERMOSTAT, not 'new-may-fail-out-of-the-box' until I've sorted this mess out.

I'd hate to do head gaskets, first time on an EA81 though, and it looks SO MUCH SIMPLER than on the EA82. We will see, I guess?

Don't worry about doing heads in USA, you have all the parts available everywhere!!!! It's a big problem in Argentina but not there! :)

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Sorry but what that p.i.t.a.factor means??

Pain in the "part that you sit on"

 

As for the problem, you still need the restriction of the thermostat or the coolant may go too fast.

 

Otherwise check the temp difference between the upper and lower radiator hoses right after turning off the engine... watch for the running fans...

 

Does putting the heater to full heat lowers the temp gauge? that will tell you that your coolant system is not up to specs....  it cannot keep the temp steady when the weather is hot,  the water pump impellers could be worn out... it happens...

 

Does running pure water lowers the temp... water is a better coolant than coolant but boils at a lower temp than coolant mix... you can add water wetter to the water.

Edited by letank
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Running straight water seemed to make no difference, but that was prior to replacing the cap and one of the hoses.

Running without the 'stat *seems* to make a difference, the needle is now running in the lower half of the range...however, it has been COLD AND RAINING AND CLOUDY the days since I took it out, so no apples to apples :P, go figure!

I went to the stupid frustrating O'Reillys the other day for a couple random things/coolant/etc. Desk clerk I got was beyond incompetent, I won't tell that story now as I'm sure we all have them. BUT while I was poking around the aisles attempting to decipher what he "explained" to me, I stumbled across the thermostats (which I hadn't asked for). Turns out people are now making "fail safe thermostats" that somehow fail OPEN if you overheat. I don't know if this means they will open IF they fail, but it seems like a step up to at least have one that will jam open if you overheat, rather than jam closed. I assume it's for more of a "when climbing a mountain and not watching the temp gauge" type thing??? Not sure.

I'm waiting for a hot day so I can compare apples to apples, then throw a new 'stat in there and see what we get. Suppose it could be the impellers--I could pull the radiator hose off easily enough and take a peak, no?

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Dear MOTM (man on the moon),

 

This is a little bit off-message (I too have an occasional, weird (EA82) heating problem, but right now, the problem is a leak with a heater pipe, and I'm trying to figure out the nomenclature), but in post #6 on this page, you mention a "heater core pipe". Is this the pipe that comes out at, or just below, the intake manifold on the driver side and connects to the heater (intake, I presume) hose?

 

I need to know because I have to replace that short, zig-zagged pipe, which only presses in, though it is anchored with a screw-and-strap arrangement to the engine at the exit end, where the rubber hose fits. What I need to know – I should probably start another thread for this unless one already exists – assuming that the animal is indeed the Heater Core Pipe, is how much junk I'll have to remove to replace that pipe?

 

The Soobie dealer says that I'll probably have to remove the Intake Manifold (a new gasket there, and I'll have to borrow someone's torque wrench!).

 

Anybody tried this before?


 

Thx!

subaruru

 

ps: I found this link for a different model Soobie that describes the animal as a heater pipe, and it clearly indicates that one has to remove the Intake Manifold, though that seemed to be only in order to extricate a broken (rusted off) pipe still embedded in the IM: (http://www.ultimatesubaru.org/forum/topic/128361-metal-heater-pipe-worn-thru-on-88-leone/?hl=%2Bheater+%2Bpipe).

 

 

pps: Actually, I just had another chit-chat with the Soobie folk, this time with the head honcho of the parts department and he checked it out for me. The pipe in question – Subaru part number 14067AA041 – is also called the Water Bypass Pipe. According to the Parts Head Honcho, it is NOT necessary to remove the IM, since the pipe in question attaches to another rubber hose that sticks out of the Water Pump. I might have to disconnect a ton of tubes and pipes that make it difficult to get to the water pump, but removing the IM is NOT strictly necessary, according to the PHH.

 

Btw, this would explain why the tube "leaks", but not a lot, and ONLY when I'm driving it: it is still attached to that hose coming out of the WP down there in the deep, dark recesses of that part of the engine, it's just that the clamp OBVIOUSLY slid down the pipe and is NO LONGER clamped around the end of the hose that attaches to the forward end of the pipe in question.


In fact, if I wanted to be stingy, I could just take that shortened pipe off [we shortened it because it had a hole at the second bend of the "Z" curve... OF COURSE, that's where it would poke a hole if erosion were to be a problem, and note that THE REASON why erosion became a problem here is that A PREVIOUS OWNER used only water, not anti-freeze (this was in sunny CA), which (the latter) contains rust inhibitors!], clean it up with a wire brush, then find that clamp down there and reattach everything... but I think I'll go with that new WBP!

 

I WILL return to this when the job is done and dusted!



 



 


 

Edited by subaruru
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As far as I know, it is not necessary to remove the intake manifold, however, doing so makes the pipe part of the job a lot simpler. Yes, it is the heater core pipe. Removing the intake manifold is not too bad unless a bolt breaks, then it's more trouble than it's worth. Might be easier to try the job with it in place first, and then only remove it if you really have to. I don't know that you'd have to replace it with a Subaru specific part, per se, any length of aluminum pipe of the right diameter should do the trick, unless you're tied tot he idea of bolting it in place.If you are worried about it rattling at all (it shouldn't( get a few extra inches of hose and wrap it around the middle to prevent too much banging.

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It's the cylinder head gaskets.  You could have it fixed in an hour for each side.  Retighten the cylinder head bolts.  End of story.

Relighting the cylinder heads is more likely to cause problems than solve them, once the head gaskets been crushed a certain way for hundreds of miles they don't like being recurshed

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The pipe that is bolted into the Intake (heater supply) really cannot be removed.  As you mentioned, it has a bolt, but the pipe is press fit too, so exctracting it would be very hard.

 

Get a new intake, or have the hole welded if you think there is enough meat still.

 

The other one from the Heater back to the Waterpump, can be replaced easily.   Although, I would say having the intake off  would be much easier.

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surface heads do gaskets make shure you use only subaru intake gaskets is critical only subaru intakes cant say this enuff only subaru intake gaskets

 

Don't forget to check block surface as well! Yes, Blocks can warp. Take it to the machinist or somebody who has a machinists edge and see if there's any warp.

 

Twitch

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