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EA82 Overcooling?!


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It seems like I run across a lot of threads regarding fighting overheating issues in EA82s. Doing a search for cooling problems & issues brought up a ton of these types of threads, and virtually nothing on overcooling. So, here's my scenario:

 

For the past two winters I've had to endure very weak heat out of the heater and a car that never seems to warm up. The needle on the temp gauge barely moves above the "C," and while the heat is enough to defrost the windshield in the winter, it's far from what it used to be. I know that the stock gauge isn't all too accurate, but the heat out of the heater is directly proportional to the heat registered on the gauge. All these cooling issues started after a heater hose sprung a leak and pumped out a good deal of coolant. The car didn't overheat, but did get mighty hot (up to the red area, by the "H" on the gauge) on the limp back home. I was assuming air in the system and proceeded as follows. After being forced to replace the radiator recently due to a deer hit I decided to tackle these cooling problems. Items that have been replaced and/or serviced:

  • New single core radiator (http://www.radiatorbarn.com)
  • New OE Subaru thermostat (went through 2 sticky, inaccurate parts store thermostats before I ponied up for an OEM)
  • New OE Subaru water pump & timing belts; cam timing is dead-on
  • Completely flushed coolant; 50/50 mix
  • New heater core heater hoses
  • Backflushed and burped heater core & cooling system

Now the car doesn't lose a drop of coolant while driving or idling, so I can't imagine I blew a head gasket back when the heater hose let go, but weirder things have happened. If I let the car idle the coolant temp and temp gauge will eventually come up and the radiator fan will kick on (199*-207* according to the manual), but once I take it for a drive the temp will plummet again and stick right above the "C" on the gauge. Could I have some freakishly weird head gasket issues where I don't lose any coolant and the car doesn't overheat, but won't come up to temp at anything but idle?

 

ANY help is appreciated as I'm getting mighty tired of driving around in an icebox!

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Is there gurgling noises when you start? that would mean air bound, it has gained a superflow for the engine rather than against. I had an 87 do this and never figured it out...aside from cardboard on the radiator to keep warm. In 32 degrees with moisture my carb used to ice all the way to the coolant filled intake :confused: . A theory was old routes got bigger in the engine after an overheat- as long as that overheat wasn't caused by a headgasket, flows get strong after killing any hose up top . It high pressured, into a super clean swollen channels. It was the best guess I got. That would be a 500,000 mile engine now :grin: . My "new" 87 after a trip down the highway for 30 miles or so, I figured to check the oil as I didn't know the car. The oil was luke warm, colder than I would wash my hands.:rolleyes: I tried blaming everything from weak fire, huge top end air flow, but with bosch platinums and thumpy idle, there is no chance of it- as a "big air" engine likes to flop around a bit at an idle unless it is low comped turbo, and bosches are precise "snappy" hot plugs. It is a blessing in disguise to have an ea82 do this....

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You could perhaps have air in your cooling system. Have you properly bled the air out?

 

Subarus are notorious for having air in their cooling systems. You need to get the radiator cap above the heater core, and run it with the cap off. Then squeeze hoses until no more air comes out the cap.

 

Could be a faulty gauge? Do you get plenty of heat through the vents when it dips to the C? Or do you not get any heat?

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You could perhaps have air in your cooling system. Have you properly bled the air out?

 

Subarus are notorious for having air in their cooling systems. You need to get the radiator cap above the heater core, and run it with the cap off. Then squeeze hoses until no more air comes out the cap.

Yep, I've had the front end way up in the air with the engine running and the radiator cap off. The engine took in a little coolant, but nowhere near what I was expecting. I may have heater core issues, see below.

 

Just had an epiphany! I think I'll try running the engine without a thermostat with the front end way up on jackstands. The old thermostat may not have been able to open fully thus not allowing coolant to circulate and get into the heater core where it could dislodge any air pockets. Run it for a bit like this with the radiator cap off, cycle fresh coolant into it and then replace the thermostat with the front end of the car still up in the air. Would this be plausible, or is my thinking way off here?

 

Could be a faulty gauge? Do you get plenty of heat through the vents when it dips to the C? Or do you not get any heat?

I'm almost positive that the gauge is spot-on. When I let the car idle the gauge will start to rise until it reaches about halfway and then the radiator fan pops on. According to the service manual the radiator fan is supposed to come on at 199*-207* so it would seem that the gauge is fairly accurate. Once I drive the car, though, the gauge will plummet and the heat falls to barely lukewarm.

 

I think I'm going to hit the garage again, loop the heater hoses to bypass the heater core and see what the engine temp does. Not sure if this would make any difference at all, but it'd be a start. Then go the thermostat removal route mentioned above and see what she does.

 

And bgd73, WHAT?

 

To quote a favorite movie of mine, Billy Madison:

"Mr. Madison, what you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent response were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul."

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sounds just like what my mazda did, 3 new thermostats, put some cardboard in front of the radiator on cold mornings and it might be ok, but your thermostat "should" close when the temp goes below its set temprature, so its not doing its job if your temp goes down to fairly cool as you start driving

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What temp T stat do you have?

I believe it was stamped 88* C when I glanced at it before tossing it in the car. That'd come out to ~190* F.

Is your T-stat stuck open? Happened to me with a brand new one, go with an OEM subie one, they don't seem to have the problems that the aftermarket has.

The thermostat is a brand new OEM Subaru unit. I already went through three aftermarket parts-store thermostats before finally resorting to an OEM. The first was a Stant Superstat from Checker which would fluctuate and stick periodically. The second was bought at Napa, I can't remember the brand or type, but it had horrible sticking problems before it'd finally pop open and allow coolant to flow. The third was again purchased at Checker and a Superstat unit (you think I'd learn...). I figured I'd try a small block Chev thermostat as some on here have recommended. While this one didn't stick, it would barely build any heat in the engine at all. Just took this one out and replaced it with an OEM Subie.

 

Edit:

BTW, this was all with 190*-195* thermostats

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Okay, after getting some seat-time in the icemobile things have started to improve a bit.

 

The OEM thermostat heats up quicker and maintains a higher temp than the aftermarket thermostats, which is nice, but it's still a bit low. So, I blocked off the grille between the headlights with a sheet of plastic cut to fit. This brought the temp up a little more and improved the heating situation. I can now drive semi-comfortably with the heat on. Do others in cold climates (at or below zero temps.) experience this overcooling of the engine when it gets cold out?

 

I'm still thinking there's some residual air stuck in the heater core. I flushed the cooling system and burped it with the old, crappy parts store thermostats in place. I can't imagine they helped the situation. I'm going to try lifting the front end, removing the thermostat altogether, burping the system and running the car with the front end lifted sans-thermostat so there are zero coolant restrictions to prevent those pesky air pockets in the heater core from jarring loose.

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"Do others in cold climates (at or below zero temps.) experience this overcooling of the engine when it gets cold out?"

 

 

<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

I do. Run with cardboard covering over half the rad. I may very well put in a bigger piece today.

 

 

Pyro

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I have a 93 Loyale and the temp gauge always goes up 1/4 of the way pretty quickly. It blows pretty hot heat for me. The weather here has been in the 40's lately and I set the heater temp half way or it'll roast me out. I'm guessing there is still something awry in your system because mine seem on par with most cars I have driven.

 

cheers,

Doug

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I do. Run with cardboard covering over half the rad. I may very well put in a bigger piece today.

Ah, good, so it's not just my car. The plastic blocking the grille helped decently, but I may now try a piece blocking 1/3-1/2 the radiator on the passenger's side.

 

I have a 93 Loyale and the temp gauge always goes up 1/4 of the way pretty quickly. It blows pretty hot heat for me. The weather here has been in the 40's lately and I set the heater temp half way or it'll roast me out. I'm guessing there is still something awry in your system because mine seem on par with most cars I have driven.

I'm thinking that the combination of cold outside temperatures, a worn-out 200K mile radiator, crappy aftermarket thermostats and air pockets in the heater core (from the heater hose explosion mishap) all contributed to inadequate engine heating/cooling and a lack of heat in the cabin. Man, when I develop issues for a problem, I develop ISSUES! The bugs are slowly getting worked out and I now think I'm down to purging the air from the heater core.

 

Back up on jack stands and burping it is! :brow:

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Hi,

 

I keep a known good aftermarket temperature gage and fittings in my tune up kit to help sort out these kind of issues. It will tell you if your factory gage is right.

 

Another thing "may" be a partially plugged heater core.

 

Really cold air...air pockets...hope you get it sorted out.

 

HTH

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okay now, air pockets in the radiator on the scale you are talking are simply an implausible explanation for your problem.. I would investigate using a higher temp thermostat, has anyone at colder climates looked into that at all?

 

The heater core side of the equation is, your heater core might not efficiently be surrendering the heat from the coolant within, to the air being forced over it by the cabin/defroster fan. You should also look into opening up the air handler box, underneath the glovebox and see if it might be partially clogged.. I live in south florida, i live in a house with window unit ACs only. the ACs are on 24/7 for at least nine months a year. Its on right now. :eek: I also smoke indoors.. and I know those coils get clogged up with all sorts of hair, dust, debris, tar and soot in about six months. Chances are some degreaser on that coil would clean up some of the 20 years accumulated nastiness. It should certainly cause a marked improvement in your heat/defogger temperatures.

 

If you drive at zero fahrenheit, then maybe obstructing your radiator is the best thing to do. Just do something temporary-like, that is easily undone.

 

If your radiator were worn out at all, it would not OVERcool. i would imagine that if you had air bubbles in there, you would be able to eliminate them by now.

 

Try to run it without the thermostat, and see what happens. I am certainly not suggesting this as a FIX, more of a test to obtain more information. You never know what will happen with YOUR car until you try it, and it might not be what you would expect.

 

thats a bit of a long post to call my "two cents.." more like a dime or so, but thats my thoughts.

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I'm thinking a partialy plugged heater core myself. You say that you flushed it, but it still could have some blockage.

 

Get the engine up to temp, put heat setting on high, and fan on high. Feel both of the heater supply hoses. Should be somewhat cooler on the return hose, but not alot cooler. If it is way cooler, you have a blockage in the heater core. To slow of a flow of coolant thru the core will allow it to cool off to much, hence the not so warm heater.

 

Both my current '86 BRAT and '88 XT6 run right at the 1/2 way mark for temp, even on the few cold days we've had here, temps in the high teens. In my old '86 BRAT, (RIP), after installing new 2 core radiator and T-stat, I could see the T-stat open/close on the gauge while driving down the road on real cold days, temps near 0*. That was kinda freaky when I 1st noticed it, like WTH is going on now???? Still had good heat out of it though.

 

My '82 BRAT had an EA-82 engine in it, had good heat out of it too, even before having to swap in a new core due to old one springing a leak. Not a fun job.

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I've got a couple solutions for ya.

Have you got A/C, and the mechanical fan that goes with it? If you do you may want to ditch it. Non A/c models use just the electric radiator fan.

 

Second, cleaning off the heater core is a good idea. If you don't have A/c it's easy. Remove the plastic duct between the blower on passenger side and the heater unit in the center. heater core and flap are visible there.

 

Also in these Subies the "fresh air" intake is always open via a vaccum controlled flap any time the heating system is on. You can recirculate cabin air only by disconnecting and pugging this vac. hose. It's easy. open glove box and squeeze the sides to open it past it's stops. Now you can see the blower box and stuff. There is a plastic tube connecting to a rubber vac line goin to the box. put a vac cap over the end of plastic line and Bam! no more artic air to try to heat. I live in Wisconsin and I plug that vac line every winter.(make sure you open a window or your side vents occasionally)

 

With the gauge reading cold as well I would guess it's a whole engine issue though. Not the performance of the heater system which you said works good at idle and when engine gauge shows hot.

Also do you have the right Radiator? maybe you got one for a Turbo?

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Well, after a few days of driving with the new OEM thermostat and freshly flushed and burped coolant there were some positive results and some unchanged results.

 

The car heats up much quicker and gets up to a higher temp with the OEM thermostat and upper grilled blocked off. In "normal" outside temperatures (anything above freezing) I've got to imagine that the car would be back to where it was a few years ago for engine temperature. Fresh cooling system components and an OEM thermostat licked this problem I think. :clap:

 

The heat coming out of the heater vents is still mediocre. I even went so far as to remove the thermostat, reinstall the water neck, raise the front end quite high off the ground and cycle a good amount of coolant through the system to purge any air pockets that may be in the heater core. While the heat is a tick better now, it's still far from where it was and should be. See below...

I'm thinking a partialy plugged heater core myself. You say that you flushed it, but it still could have some blockage.
That's what I'm thinking now too. I'm going to try some radiator flush in the system and swap the heater core hoses to backflush the core. After 200K and 12 years I'm sure the heater core has built up its share of scale and deposits. May work, may not. I can risk the $7 in radiator flush solution if it doesn't work (and possibly having to score another core from the boneyard).
Have you got A/C, and the mechanical fan that goes with it? If you do you may want to ditch it. Non A/c models use just the electric radiator fan.

 

Second, cleaning off the heater core is a good idea. If you don't have A/c it's easy. Remove the plastic duct between the blower on passenger side and the heater unit in the center. heater core and flap are visible there.

 

Also in these Subies the "fresh air" intake is always open via a vaccum controlled flap any time the heating system is on. You can recirculate cabin air only by disconnecting and pugging this vac. hose.

The car came with A/C, and still has the compressor mounted and belts running it, but the mechanical fan, lines, condenser, accumulator and some misc. wiring have all been ditched. There was a leak somewhere that depressurized the system and I used it so infrequently here in MN that I figured I'd just get rid of the whole business.

 

Even though the evaporator won't make it fun, I'll try digging under the dash to clean the exterior of the heater core. Can't hurt, I figure.

 

Finally, I had no idea about that fresh air recirc fitting! I may have to plug this line after all the cleaning and backflushing is done to see how it affects the heating. Coming from another northerner, it sounds like this is the voice of experience. Thanks!

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What if you do have A/C? Then how would you clear out that heater core?

 

The A/C evaperator is in between the blower and heater core, were the empty duct would be on a Non A/c. To remove it you have to disconnect the refrigerant lines and a couple bolts and it comes out like the empty duct does. But if you want to keep your a/c workin you then need to recharge.

 

If your A/c doesn't work or has been removed than go for it without worry.

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i dunno - i live in Wisconsin as well, but have no issues with the heat in my car - stays plenty warm on all but the most frigid days (temps well below zero F) also to be noted, my car has 244K on the clock, and i havent done anything with the cooling system other than check/top off coolant periodically.

The other half's car has had the radiator replaced, as well as the thermstat (non OEM - 180* unit) and his seems to be working fine too, albeit not quite as warm as mine - altho he does have an issue with the control setting not wanting to stay on the floor heat function (some sort of vacuum line issue with the flapper that directs the heat)

sincerely hope you can get the issue resolved before it gets too frigid out there.

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UPDATE

The icemobile is no more! Dug into the cooling system last night and I now have normal engine temps and toasty, warm heat in the cabin.

 

Low Engine Temperatures

The combination of faulty aftermarket thermostats (main problem), low outside temps (20* or lower here), 200K mile original radiator and buildup & scale in the cooling system all contributed to the engine rarely getting up to full operating temp.Fixes to the problem:

 

Low Heat Temperature in Cabin

After burping the system multiple times with poor results I figured the heater core must be fairly plugged up. Oh yeah, that was an understatement! Some of the gunk that came out of the cooling system after running the Prestone cleaners through it was unreal. Fixes to the problem:

I temporarily swapped the inlet and outlet on the heater core in an attempt to backflush all the gunk out of it. Worked like a charm! I followed the instructions on the Prestone cleaners to the word and could feel the heat warm up as the car idled. After some driving with the cleaners in the system I swapped the heater core hoses back to their original orientation, installed a flushing tee into the inlet of the heater core hose and flushed the system out with a garden hose attached to the tee. Whoah! I'm embarassed to say that the cooling system was highly in need of some R & R. There were literally clumps of brown goo that were coming out of the radiator during the flushing process. Once the water ran clear I drained it all and refilled with a fresh 50/50 mix.

 

The cooling system is now fully up to snuff, the car gets up to temp quickly and maintains normal engine temp and the heater blows mighty hot air now after the cleaning and flush. Heat rocks!:headbang:

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