How hot is Too hot?

[markjw]

I've been messing around with this '91 legacy wagon for a few days. It had a failed water pump when I got it.And,the PO said she defenitaly overheated it.To what extent,i don't really know.

 

After repairs,I have driven it about 150 miles,mixed driving,and have overheated it twice.Both times the needle didn't reach the red,but got close,and I was able to turn the car off within seconds of the temp spikes.

 

So,at this point,I am going to replace both HG's and all related cooling components with OEM stuff.

 

I'll take the heads in for pressure testing and flattening.

 

My question is,with this much overheating,might there now be other problems that a standard,quality HG job won't fix?

 

Are there other things to consider,aside from normal HG work, now that the car has been overheated a few times?

[bheinen74]

is it requiring adding any coolant?

NO coolant useage and overheat means either water pump, fans not working, or air in the system needing to be burped, bad thermostat, clogged radiator etc.

 

Coolant useage, means, leak, or headgaskets.

 

Please state if your cars coolant has been going low. I don't doubt this, but we need more details before going the ej22 has a blown hg route.

Edited January 5, 2010 by bheinen74

[ericem]

my old 93 leg with 300k was overheated to the point where there was barely any coolant and it was pointing at H with the car bogging for a good 2 weeks because of a water pump leaking.

 

After replacing the waterpump, the car ran fine with no more overheating, had the original rad cap, thermostat, hoses etc just the water pump was changed. And drove like that for 50k+ with 0 issues overheating wise.

 

Id start with this, when the engine is cool, remove the rad cap, see if the rad is full, make sure there is fluid in the overflow, and start it up with the cap off. See if bubbles start floating up continously, and squeeze the upper hose a few times to burp out the bubles.

 

Also could be a bad thermostat. Be sure to use all OEM parts!

[nipper]

How many miles are on this car. Do a wet and dry compression test to see if there is any ring damage from over heating.

 

Also you will need to do an oil change. Oil on modern engines (funny how modern is 1990) is also used to do some of the cooling, and i am sure at this point it is quite stressed.

[markjw]

It's not using any coolant,but the expansion tank is showing a constant stream of bubbles after it warms up. I have burped it so many times now (following the recomended ways of the USMB archives) I lost count.All done on ramps.

 

I have replaced the thermostat with three or four othere's with the same overheating results and I have tried three diffrent rad caps,all with the same pressurized,overheating,cooling system results.

 

Initally,I replaced the failed water pump with a new one,and a new timing belt,so I think that part is Ok.

 

I don't want to overheat the thing anymore.Really at this point,I've decided I'm going to re-seal the motor no mater what. I'm going to use this ride to get me to work and back. 240 miles,round trip.So,I need it to be reliable.

 

I'll do the comp. test before I tear it down,but I wanna get some of the "stuff" out of the way. I'm kind of double posting here.I went over alot of this in my timing belt thread. My apologise.

 

So,what I'm wondering,is this motor worth re-sealing with all the overheating that's been going on,or,should I find another? From what I've read,they are pretty resilient motor's.

[Log1call]

When you do the gaskets you should replace the thermostat because overheating can bugger them even if they were good before the overheating. I'd also get the radiator's top tank replaced because they can clean inside the radiator properly with it off and I'd replace it because the plastic doesn't like excessive temperatures and gets brittle at just a few degrees above normal running temperature and they do crack after an overheating... the tanks are quite cheap.

 

When you have the heads off you should inspect the bores for signs of overheated rings or broken rings. Now this is a tricky one unless you have had some experiance with looking at ring wear marks. If the rings are good they leave a nice clearly defined ring of carbon at the top of the cylinder where they don't rub. The carbon will go right around and have a clean line where the ring has been to. If the rings have broken, they will probably be rubbing still in places and not in other places, so you get a clean cut line of carbon that extends down the bore a certain way and it will be on the left of the break say and to the right there will be a clean bore up to the usual line. If the rings have overheted they soften and stop scraping so well and you normally see a hazy film of carbon that sort of starts at the top a bit dark and then gradually fades away down the bore. Often the carbon is not dark or black but just a medium brown colour. As I say, you need to have a bit of experiance to spot the differences. Put one cylinder at a time down and give the bore a light wipe with a clean cloth. Don't rub too hard or you might rub off any tell-tale carbon. Get a light and a mirror if the motor is still in the car and have a good look all the way around the top ten mills of the bore. If you can see a nice clean line of carbon then all is probably good. If the line is interupted or if it fades away down the bore you have a potential problem and you should try and get someone to look at it for you that has seen these things before.

[markjw]

Thanks,man...Good stuff. I have seen the carbon line you are talking about,but I had no idea of the significance of it. It makes sense that an uneven line or fading line would suggest ring damage. I intend to replace the radiator and the thermostat,too.

[Log1call]

You are welcome. I have been looking for photos online but there aren't many suitable ones I've seen yet. Here is a bit of an extreem one... I hope yours don't look like this, it has broken rings that have been broken for a while... http://media.photobucket.com/image/damaged%20piston%20rings/winterheating/Image1932.jpg

 

If I can find a picture of overheated rings I'll come back.

 

Ok, I couldn't find a picture of heated/softened rings but in that photo you can see the top ring is broken and has been for a while. Just to the right of the break there is some partial leakage, that's about what soft rings leave behind, except it extends further around the bore than that narrow strip shown there. Also, the second ring wears the carbon partialy off so you have to sort of interperate what you are seeing. I'm sure you will figure it out now that you have the idea. Hopefully you will find a nice clean carbon ring anyway. Good luck with it.

Edited January 6, 2010 by Log1call

[markjw]

Well,my cylinders don't look that bad. I can't detect the carbon ring. I know what it is,I've seen it before,just not showing well in these cylinders. At least I can't see them. I know that the subject of assessing head gaskets is a much debated subject,but I wanted to post a couple pic's,anyway. The lower portion of both HG's,around the water jackets are in Very bad shape,especially on the 2&4 side. If I had to guess,I'd say the gas intrusion is at the dark spot,on the metal ring,in the first pic.

 

There are some dark areas within the cyl..They run lenght wise within the cyl. wall. (Pic #2) They are as smooth as the surrounding area,but I don't recall ever seeing them before in other cylinders. Any one have any ideas about them? Heat spots,maybe?

 

[markjw]

I took the heads to the machine shop today. They'll be ready on Friday. I went to the Subaru dealer,too. That didn't go so well. I could only get the Headgaskets, thermostat and exhaust gaskets. The intake gaskets are a week out. So is the radiator cap. I can't wait that long. I'm going to have to go with whatever NAPA can get.

[ericem]

Hmm, get them online and pay express... That's sad no rad caps on hand?!!

[johnceggleston]

The intake gaskets are a week out. So is the radiator cap. I can't wait that long. I'm going to have to go with whatever NAPA can get.

 

those two are not the critical parts. i wouldn't worry, you'll be fine.

[markjw]

those two are not the critical parts. i wouldn't worry, you'll be fine.

 

I was hoping someone was gonna say that. I'll eventually get a oem rad cap,but I really don't wanna pull the intake off after I wrap this up. Wow! Much more involved than the ea's I have been working on. But,I like the fact there is no water passage in the intake.

 

About those head bolts. Are we positive we can re-use them? I have done HG on other vehicle's where the general consensus was to Not re-use stretch bolts.

[bobaru]

I get my parts at roopair in tacoma order them at 9am get them around noon better than NAPA parts...... just as good if not better as sube dealer parts and cheaper

[markjw]

I checked out they're website,Bob...I'll have to stop by there when I get up to Tacoma. Thanks for the tip.

 

I can't get OEM intake gaskets till the end of next week. I can't wait that long 'cause I'll forget how to put the motor back together.So, I bought these over at Schucks. They are better quality than I expected. They are some kinda multi layer metal gasket. Should I spray the copper on them,or install them dry? What do you think?

 

[ericem]

Install dry, and make sure surfaces are clean. Don't think twice.

[GeneralDisorder]

Don't worry about those intake gaskets - unlike EA cars, the EJ's don't run coolant through the manifold so those aren't critical. Just install them dry.

 

The radiator cap should be fine as well - just pickup a Stant or CSK or whatever japanese brand you can find. Avoid the cheap chinese stuff. Name brand or japanese.

 

And yes - reuse the head bolts. They are not torque-to-yeild so you will be fine. Wire wheel them and run a tap into the block. Make sure you coat them in oil before you install them to insure they don't bind while torqueing them.

 

GD

Edited January 8, 2010 by GeneralDisorder

[markjw]

It all went well. My brother in law stopped by at the perfect time to help me get the heads into place. It woulda been a real hassle without him there to manipulate the head bolts and stuff while trying to get the heads on the block.

 

If the frame rails were another quarter inch closer together,I dont think a guy could do this job without pulling the engine. It's a really tight fit.

 

I've put bout 30 miles on it so far. I see no bubbles in the reservoir tank,and the heater blower isn't going cold anymore. But,the engine seems to run a little too hot,still.

 

I don't have a real temp gauge,or a lazer heat gun,but the needle on the dash stays rock solid at a little less than half. It gets there quick,and doesn't move up or down until I turn the car off. I'm thinking about getting a new radiator,but I'm wondering what everybody else's temp guage reads under normal operationg temp? Also,I just have plain H2o in there right now.Maybe when I add the coolant,it'l run a little cooler.

 

1992 leg. ej22

[Log1call]

Good work.

 

The gauges are just an indicator really, not an accurate gauge. If it gets up to operating pressure quickly then stabilises, gets slightly hotter on a big uphill then slightly cooler than normal running temp on a long downhill it will probably be right.

 

You also get a pretty good idea if the cooling system is operating correctly by the duty cycle of the fans when the car is idling. If the fans come on for one in three it's about right. If they are on one in two the cooling isn't working well. Some cars they come on one in four or more. Sometimes it's one minute out of four they are on, other cars seem to stay on for more than one minute but then they take longer to come on next. Probably varies a bit with the ambient air temperature.

 

You can also tell a bit just by holding the top hose... If it's just barely too hot to hold then it's about right.