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-   -   Another overheating problem... (http://legacygt.com/forums/showthread.php?t=203203)

mailman 03-09-2013 08:46 PM

Another overheating problem...
 
...with my 96 2.2.

In the past month I've changed the thermostat, radiator, radiator cap. The thermostat went out and I discovered the PO had somehow chipped the upper radiator hose connection. Ran fine after that.

A couple of weeks ago, about 2 hours into delivering mail, it overheated. I didn't really know why it was doing it, so I let it cool down, and followed the burping procedure while filling it- slowly. But, it kept overheating every 45 min or so. I checked that the fans were working, bled it again, and drove it for about 80 miles on the highway- no overheating. I figured everything's fine, right? Just an air bubble?

I drove it around town all week with no problems. But the next week when I did the mail again, in almost the exact same spot, it overheated again. I bled it and filled it, and it maintained correct temp., but the heater would only blow hot when I accelerated- when idling it would go cold. I bled it again a couple more times (every 45 min or so). The last time I bled it, it made it for the rest of the route (about 2 hours) without overheating, and I made it home fine.

Next day, in almost exactly the same spot, it overheated again. Same issues, heater only hot on acceleration, etc.

At this point I knew there was something really wrong, so I asked my mechanic and non-mechanic friends. Their ideas:

-Water pump fins corroded causing cavitation and air bubbles
-Heater core clogged
-just overheating from the hard conditions (it hasn't done this before and adding wetter water didn't change anything)
-Transmission getting too hot, trans fluid is actually heating coolant instead of being cooled.

I wasn't able to get it to overheat again, but on a quick trip to the store it heated up to operating temp and the heater was blowing cold at idle. On the way the heater worked, and when I stopped it continued to work, although it was noticeably hotter when revving the engine.

Frustrated and still thinking I didn't bleed it enough I took it to the dealership to have it flushed. Their contribution- bad headgaskets. "These cars had head gasket problems" -"The 2.5s did" -shrug-

After some observation I realize that the radiator is not pulling coolant back out from the reservoir. There are no noticeable leaks in the res. hose or anywhere else visible. Water pump isn't leaking as far as I can tell.

I'm not saying it isn't the headgaskets, but there are no other symptoms. Another theory I read about is that there is a minute crack in the block which, when the engine heats up enough, causes the system to lose pressure and thus the vacuum to draw coolant from the res.

Plus, I'm really hoping it's not that. I was hoping it was an air bubble to avoid doing the water pump or heater core :stupid:

pleaidestar 03-09-2013 09:07 PM

The bypass hose to the heater core pinched off or something g to that effect if its somewhat random maybe?

That would be a bummer if the block was cracked...whats the history on the car? Did it have prior headgasket failures? Sorry, I haven't read through you other posts.

mailman 03-09-2013 09:27 PM

I've only had it since Sept. and am the 3rd owner. 1st owner kept up with it and I have all of her maint. records. 2nd owner didn't keep records, I think her husband did a lot of the work himself. The front diff was filled with ATF and the green diag. wires were connected when I bought it. Still, they did or at least attempted to do regular maintenance on it. 187k miles and 6k of those are mine. All I know is that it's had a lifetime of stop and go driving.

Kennyfvholla 03-09-2013 10:04 PM

What brand of parts did you use? Sometimes cheap, or non-OEM parts will not fix an issue at all....

EJ22E's are not known to have head gasket problems like the EJ25D's do. But, that's not to say that it can't or won't happen. You need to have someone check to hydrocarbons in the coolant. If no one will do it, order a tester online and do it yourself?

Now, you say that the system is not creating any vacuum at all and will not draw coolant from the overflow reservoir. That points to a leak of some sort if it's not a bad radiator cap. You can buy a dye kit and use a black light to see if you can't find any visible leaks.

Do you smell coolant at all? Does coolant overflow out of the overflow reservoir?

Do you know when the last water pump / timing belt job was done?

How exactly are you purging the air from the system when you refill the coolant?

You can always try driving in a lower gear to keep the RPM's above 3500 or so while it's overheating. When my drivers side gasket went bad, revving the motor like that while driving would cause the coolant to cool down to normal because it was moving so much more coolant.

snederhiser 03-09-2013 10:16 PM

Hello;
Here are a few ideas! The problems you are having are related to three things, water pump, radiator, or thermostat. The heater is telling you that there is not much flow at low rpm's. The thermostat should have a weep hole in it. The timing belt could be stretched to the limit and not putting enough tension on the pump to drive it, or the fins are rotted away. The radiator is plugged not allowing coolant to flow properly. When the engine is hot, pull the plugs and do a compression test. This may pin down a head gasket issue or cracked head! Steven.

mailman 03-09-2013 10:17 PM

I used Subaru thermostat and whatever cheap radiator and cap I could get from Napa on short notice. I tried to get a cap from Subaru but they didn't have any in stock the day I went. I should probably order one.

I'm going to try and get a tester tomorrow, or order one online if I have to. I'd rather figure it out ASAP since I have to deliver Monday. I forgot to mention that I had a radiator shop test it, but they couldn't get it to overheat even with the radiator blocked off...?

No smell of coolant and it does get pushed into the overflow, however it doesn't overflow. It gets pretty full though, almost to the top from the full mark.

Last timing belt record I have is 1999... no idea if anything's been done since.

I followed the directions in that one thread, haha- open valve, open cap, fill very, very slowly, replace cap, replace valve

Kennyfvholla 03-10-2013 07:41 AM

You need to get a better than cheap radiator cap. The fact that the reservoir never overflows is a VERY good sign that your issue is not with the head gaskets.

You NEED to get that timing belt looked at, and possibly changed. 13 years on one belt regardless of mileage is pushing it a bit. You shouldn't need one, but it you do and it's slipping on the water pump, that could be your issue.

Mind you, when you fill the radiator, you'll have to stand there for a good 5 minutes or so. You'll get to the point where you are barely putting any in and it fills. Once you get to that point, you're almost done. You also need to squeeze the upper radiator hose in order to help trapped air out. After that, fill up the reservoir. Run the car until it is up to operating temp. If you have a properly functioning cap, it'll get pulled back into the system once it start to cool down. Then keep an eye on the reservoir and fill as needed to keep it at the "full" line.

I think your first course of action needs to be the radiator cap. Buy a better one, even if it's not OE. After that, then go get the hydrocarbon tester if it starts to overheat again.

The Napa close to you has one of these in stock:

http://www.napaonline.com/Catalog/Ca...904_0257303672

Try that one. Or go try a good (non-lever) Stant cap from Advance Auto.

johnegg 03-10-2013 10:32 AM

what happened first, changed the T-stat, or overheated?

when filling with coolant, if you are not removing the vent plug on the rad by the top rad hose, you are not filling it correctly and it will over heat.

no heat at idle but heat when accelerating indicates to me that the coolant is NOT circulating ay idle but is at higher RPMs. this could be the water pump or it could be the low coolant.

do an advanced search of thread TITLES ''how to fill and burp the cooling system''. or just the words ''burp cooling fill system'' in the title.

good luck.

let us know what you learn.

snederhiser 03-10-2013 04:47 PM

Hello;
This is sounding more like a water pump issue. The pump and the heated water should provide enough pressure to slightly open the cap to allow heated (expanded) water into the overflow bottle and when the car is shutoff and the water is cooling to allow coolant from the overflo bottle to flow back into the radiator. Also check the coolant lines that go to the throttle body and the IAC valve. Found a bad one on a recent repair that was done. Steven.

mailman 03-10-2013 08:15 PM

1 Attachment(s)
thanks everyone for the advice. I bought that radiator cap and a compression tester. Jhnegg, that's the thread I followed when filling.

I don't know what the proper order is, but I numbered the cylinders starting with the driver's side (remember RHD) #1, in front of that is #2, passenger's rear #3 and front #4.

Compression test results:
1: 155
2: 130
3: 80
4: 120

My Haynes manual says 156-185 is normal. All four held steady with no fluctuations.

Here are the spark plugs from the passenger's (low) side; one has been cleaned. Sorry the pic didn't come out very nice but you can see the buildup. These spark plugs are ~2 months old.

When I bought the car the #3 spark plug was loose, and when I pulled it it was in really bad shape compared to the other three. Last time I was able to secure the new plug, but this time I had trouble getting it to seat properly in the threads. It would get snug but not tighten.

According to the book, here's where I'm at:
-Valves
-Headgasket (since one side is low- however, no other symptoms)
-Cracked block
-Camshaft exhaust lobe (if accompanied by a rough idle, which started in the middle of a road trip a couple of months ago)

What to do now? Pull it and replace the headgasket, valves, camshaft? I've never worked on the guts of an engine before.

johnegg 03-10-2013 09:00 PM

cylinder numbers

.......rear
3.............4
1.............2
......front

at a glance it looks like the timing is off.

the ej22 engines do not blow head gaskets often. but if they do you can usually see bubbles in the overflow bottle on the rad when it is over heating. this is the exhaust gas escaping into the coolant. this is one way head gaskets can cause over heating. other ways is is if the coolant is leaking into the combustion chamber and burning causing white smoke or if coolant is just leaking out on to the ground. but exhaust into the coolant is usually the one than causes over heating in 45 minutes.

and if the head gaskets do leak into the coolant, it usually does not affect the compression until WAY late in the game. 180 psi is a lot of pressure, but not as much as is generated when the fuel air mixture explodes. and a cooling system pressure test usually does not show anything.

is there black? gunk in the coolant overflow bottle, or in the rad?

before i committed to a head gasket job i would make damn sure the timing is right. if the left side cam (when seated in the car) jumps a tooth or 2 it can mess up compression. how old is the timing belt? what all was done when it was replaced?

but if the timing is right, then the compression has to be going somewhere. and the timing being off does not explain the over heating.

what happened first, changed the T-stat, or overheated?

mailman 03-10-2013 09:16 PM

Last timing record I have is 1999 and like 60k miles or so. Not sure if it's been done since, but it sounds a lot better than tearing the engine apart completely.

There are no bubbles when it's overheating, no smoke, no gunk in the coolant.

johnegg 03-10-2013 09:30 PM

Quote:

There are no bubbles when it's overheating, no smoke, no gunk in the coolant.
to me this indicates something other than head gaskets.

at 60k miles the timing belt is due. if you plan on keeping the car do the belt, water pump and all 3 idler pulleys.

but before toy do anything you need to find the cause of your heating. either a leaky hose or clamp or a bad rad cap, or .... ???

maybe add some ''dye'' to the coolant and see if you can find the leak. you can get a ''black light'' bulb at the hobby shops (AC MORE or FRANKLIN???) pretty cheap. cheaper than the parts store.

snederhiser 03-11-2013 09:07 AM

Hello Mailman;
Let's face reality here and just admit that a head gasket is going. Do not throw any more money at this. I have had recent experience with this same thing. You can do two things at this point, find another engine or fix yours. Were here with excellent advice. I spent $500.00 on saving my engine, doing the work myself. I do automotive machine work, so kinda hip on this, Steven.

Kennyfvholla 03-11-2013 10:05 AM

Actually, Steven, all the signs so far are actually pointing more towards the timing than anything else at this point. Anything that we have suggested to replace would not be considered throwing money at it. He NEEDS to replace his radiator cap and thermostat with OEM or OE equivalent parts, he NEEDS a timing belt along with a water pump and timing pulley set. Those are regular maintenance items that he's do for. One or more of those parts could actually be what is causing his issue. If not, that's when you go after the head gaskets. At that point, he will not have wasted money at all....

Mailman, check your timing like John has suggested. It will help decide what to do next. If it's off, fix it and see if that helps. You do need a timing belt, water pump, and timing pulley set at this point. So if it does help, replace those and be on your merry way. If the head gasket is going: You WILL see bubbles and gunk in the overflow reservoir and the coolant system will STILL create vacuum as it cools and pull coolant from the overflow reservoir. To be 100% sure though, you need to do the hydrocarbon test... But first, see if you don't have a coolant leak from somewhere using a black light and dye like John and I have suggested. Kits are inexpensive..


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