jac113

iTrader: (4)

Hello all,
I've been having cooling issues with '92 5.0/5pd since I bought it back in April and has recently been getting worse. First it would run hot on the highway but would never go over 240. I noticed a leaky o-ring on the radiator and fixed that. Then the water pump went out and I fixed that. I installed a colder t-stat but not much help. With no other leaks I noticed that the coolant was still being lost somewhere but never got smoke out the tailpipe or coolant in the oil. Finally I read somewhere that if the coolant suds or bubbles out of the radiator when warm then that means that exhaust gases are getting into the coolant through a crack in the head gasket. So I took off the rad cap and warmed up the car and sure enough the coolant bubbled out like a sud machine.

Knowing this, I knew that my time was limited so while saving up for the head work I noticed the car running a little hotter and hotter and recently starting getting in the red, 250-260 degree area. The coolant has boiled over about 4 times now and am wondering how much damage i'm doing to it. The car has never shut off from being hot. I don't mean to run it until it gets in the red but once it reaches 220 degrees it doesn't take long get to 260. I'm going to get the gaskets changes and heads rebuilt this week but are more concerned about the 200,000 mile short block.

Can I have damaged any rings/pistons/bearings? thanks

camaronewbie

You may have a head issue, and if so you really should not drive the car at all. You could crack a head if it's not already, seize the motor, etc. by letting it get hot like that. You're definitely ruining the oil as it's breaking down from the heat, and it will no longer protect the block.

If it's simply a gasket, that's not a hard job to do yourself - if it's a cracked head, basically the same easy job - just need to get a replacement (can usually get rebuilt stock heads for under $300).

But - what caused the issue? That's what you need to determine, or it will just happen again.

1) Does it have the air dam located directly under the radiator?

2) Are the fan(s) coming on, and at what temp?

3) Is this a TPI or TBI car?

jac113

iTrader: (4)

Dunno what caused the problem. Does not have the air dam, fans come on at about 225 and turn off at 214 if I remember right. It's TPI car. Can cracks in the head be repaired during the head job or need to be scrapped?

thanks

t-top havoc

iTrader: (3)

The air dam would help, IMO. I can say ours runs cooler with it!!
Some ppl say they have no probs without it.

If the head(s) cracked, it may be easier on the bank to get reconditioned head(s).

As far as you know, was there ever any type of leak sealer put in the rad to seal leaks?

jac113

iTrader: (4)

no sealer that I know of. In hindsight, i'm thinking that the previous owner knew something about it. Why else would you sell a B4C for $1700, yet I drove it 90 miles home with no problem. My problem now, so i'm going to get heads pressure checked and fluxed hopefully by tomorrow or weds to see what the damage is. In the last 4 months it's never overheated like this so I think a crack would of shown up sooner. I can get an air dam pretty easily but with a suspect cracked gasket i decided to deal with this first, like you said, many people don't have problems without it. Besides it would overheat at idle so that throws out the damn dam.

i'll pray that the head is not cracked because that will force me to buy some L98 heads which wouldn't be so bad for the car but worse on the bank.

Killert

iTrader: (9)

Put the Aim Dam on first. Our cars really need them to stay cool.

Is there oil in the Antifreeze or Antifreeze in the oil?

jac113

iTrader: (4)

no coolant in oil but the antifreeze was looking a dark yellow compared to the new coolant. Not sure if that's due to oil or just dirty internals. I'm pretty convinced that I need to move forward with changing the gaskets bcuz of the foamy coolant and loss of coolant over time. i'm going to get the dam, but since it overheats at idle that be only one of my problems.

ASE doc

The bubbling coolant is a failed head gasket. Its the first clue I look for. An HC test of the coolant gases will verify it but if its bubbling when cold, I wouldn't bother testing. Your biggest concern with running the engine like this over an extended period will be cracked heads, especially with the thin walled castings used on your motor. The next concern would be stuck rings from overheating the piston tops.

Honestly, I would not recommend replacing heads on a 200,000 mile engine without a bottom end rebuild anyway. The likelihood is way too high that you will end up with ring smoke and severe blowby when you clamp down new heads on the worn out cylinders, pistons, and rings.

jac113

iTrader: (4)

So the heads finally got pulled off today and sent to the shop. The mechanic that pulled 'em said that the head bolts were not very tight when he took them off. He also did not notice any breaks in the head gasket. I didn't see the heads when they were completely off but looking at the side of them when the intake was off you could see the burring marks from what seems to be a recent head job. I'm curious to know if minor unnoticeable cracks in the gasket could leak exhaust fumes into the water jackets. Worse case scenario, the head would be cracked right, but there's no coolant in oil or oil in coolant.

any ideas anyone....thanks

jac113

iTrader: (4)

update:
I got the heads back from the shop on Friday. the did a complete head job and the machinist told me that the heads was not cracked but severely warped. He said that the variation on the surface was 8 thousandths of an inch, enough to let water through. i'm putting the heads back on and hoping that was the problem and not a crack in the block.

avilla20

any updates? im curious if my car might have same problem.

Maeryk

What is your car doing? Number one clues to head issues are cross-contamination of fluids. Oil in the coolant, or vice versa.

course, overheating can also just be a stuck thermostat that never opens, a clogged rad, bugs in the front of the rad, bad fans, airflow, etc etc. I don't jump to assuming a head gasket/seal problem unless I see something that indicates that over a simpler, easier fix.

avilla20

its leaking a tiny bit of coolant from the overflow bottle neck, i just updated the thread so it should be towards top.https://www.thirdgen.org/forums/cool...ttle-neck.html

i check oil and coolant every time before i drive it, besides losing oil due to valve cover gaskets, both are always clean.and after i replaced the water pump and heater core coolant was puking from rad cap so i was terrified of head gasket leak and had my coworker use the smog machine to sniff hc's and it passed and my coolant doesnt smell like hydrocarbons....
but anyways lets not steal this post....on with the updates!!!!

jac113

iTrader: (4)

update 2-not 100% yet,
I just got everything together last night and finally cranked it over at about 8:30pm. Sorry taking so long but I had to figure out what bolts/parts went where since the guy I had doing the work bailed on me after he took the heads off. I guess $150 for r/r was a bit too low, he kinda underestimated that one cuz I wouldn't do it for less than 3

So to recap, the car has no air dam,still doesn't, it always ran in the 240 range on freeway(probly air dam issue) and cooled down at idle to 220. After changing faulty pump, sealing the plug on radiator and putting sealant on reservoir cap, the car would slowly over time start to run hotter and creep towards the red zone, even at idle. I foolishly ran it that way for a while, since I didn't have the $ for the work anyway and I work about 2 miles from home. eventually it would overheat to the point that the coolant boiled but it never shut off within a 10 minute drive. The coolant would also phizz up when warm.

Now for the build, I have to throw this in because I spent so much time doing it:

putting on the heads: Driver side no problem, just climb in the car and angle the head to where you can see the dowel pins line up and drop in place.
passenger side is a hastle b/c it was hard to hold the heavy cast iron head in place long enough to line up pin. I tore/bent two head gaskets this way because the exhaust tube forces you to hold the head in a awkward position. Finally I did it from outside the car, reaching over the fender.

adjusting valves: I had to learn this one: there's a link somewhere online that breaks it down real simple. Bring the #1 piston to tdc compression stroke and you know it's there when the lifters are both in their lowest position, or on the flat side of cam lobe. If your at tdc and not compression, then #6 piston is at tdc compression. either way with #1 or #6 at tdc there are certain cylinders and valves that you adjust, 8 valves for #1 at tdc comp stroke and 8 for cyl#6 @ tdc comp stroke. I adjusted them to zero lash(no play) + 1/2 turn and I hope that works.

Intake manifold runners and plenum - these are pretty simple just don't forget the coil bracket on last two bolts on passenger side, I did. Don't snug down the runners before you put the plenum on, you'll need that play and snug it all down evenly in steps both sides at same time.

exhaust manifolds - driver side no prob.
passenger side is tough, i've read where people took off the a/c tank to make room but I managed to get a few threads in on all bolts without doing so. I tightened it down from top and under the car.

When all said and done, I had 3 torx head bolts left over and 3 brackets that support I think the alternator and a/c, still have to figure that out. I still have to find out how the long tube is routed that goes behind the engine to both sides. i'm guessing it goes to the exhaust rail on driver side to something on passenger.

I did buy a radiator from autozone for $91 just in case my old one was bad. Rad shop wanted to charge $80 for a flush so I just got a new one.

Now for the real update: I got it started and must have stabbed the distributor perfectly because it'll start with just a click. The problem is that the new rad took more than the 2 gallons of 50/50 mix that I had so I couldn't keep it on for long. Going to fill it up today and let it warm up. I did notice during the short while that it was running that it's missing like crazy. Pressing the gas bogs it down. I must have crossed injectors wires or plug wires or both. I get that straightened out tonight too.

Sorry not much of an update but if any questions about the build let me know. I do know that if it continues to overheat than the block must be cracked because the pump, rad is new and the fans work. I did notice the t-stat being stuck but was not the main reason it was running hot I'm putting in a 180 deg. stat for now until I buy a better one from napa or the stealer.

jac113

iTrader: (4)

another update:
So I correct my injector wiring and now the engine idles smooth. I don't have as much power as I used to and i'm thinking it might due to the timing or possibly valve adjustment I don't have a timing light but i'll get a scanner today and see where it's at.

Bad news though - after it warmed up the temp started to creep over 220. It probably got to 225-230 and I shut it off. With a new rad, water pump and thermostat I figure it would handle the heat generated with bad timing.

Today i'm going to buy a 195 t-stat from Napa, I currently have a 180 from autozone in and it might be sticking. I noticed the 195 t-stat that I had in it before was sticking. I'm also going to get a new rad cap. I'm hoping the car stays cool after all this, if not dunno what else to do.

When looking at my timing on the scanner do I unplug the timing advance cable on the passenger side to set it and what should I set the timing too? It's a '92 5.0 TPI all stock.

thanks

camaronewbie

Yes, unplug the EST wire to check/set initial timing.

Don't see how a 15 hotter stat is going to help a heating issue - I'd test the 180 stat if I was concerned - put it in a pan of water with a cooking thermometer, boil it, and see what temp it opens at.

220-230 is not overheating - it's about normal for a factory setup - even 240 is normal, alot of fan switches are set for 238.

jac113

iTrader: (4)

ur probably right newbie. after talking to the machinist who did my heads he said be careful that the temp does not climb over 220, sumptin about the heads being sensitive to warpage. i think all the time I spent doing the work has gotten me a little panicky + i keep hearing about other cars that stay around 195 so I figure 220 is high already.
As far as getting a hotter t-stat, there are those that claim that a cooler stat will make the car run hotter. I don't agree with it but in a way just hoping they are right. My fan turns on at 224 and off at 214.

what should I set the timing to?

oh, and I got the air dam yesterday and will probably put it on today.

GTA Sammy

iTrader: (1)

6 degrees BTDC
By the way.... I have a cool T-stat and my car usually runs close to the boiling point.... unless I'm on the highway.
100*C= is the boiling point in a metric system, mine often runs around 95*. 95 degrees Celcius=203*F

Have you ever thought of using "Water Wetter" it helps the coolant dissipate heat better. (Google it)
Are you running the appropriate coolant mix?

camaronewbie

I could see where it's possible that ... a cold stat could open too soon, allowing the water to circulate and cool too quickly, making the sensors think the car is still cold, thus ECM makes it run rich as if it were cold, and maybe running rich for too long can make the car warm - but that's a real stretch of logic. You'd never have that issue with a 180 as most folks here have been running 180's for years.

jac113

iTrader: (4)

Well I just swapped out the 180 for the 195 during my lunch break. The 180 didn't feel like it was stickin but with a good cooling system the temp should still be normal with the 195 t-stat. I'm running 50/50 mix, it took about 3 1/2 gallons.

When I get home i'm going to put it on the scanner and set the timing right.

Let's see what happens.

GTA Sammy

iTrader: (1)

If you're trying to keep your engine "cooler" going to a hotter T-Stat is counter-productive.
Living in Canada where the temp is -40* half the year has made me understand thermostats since I was 5 years old..... You see, when it's -40 outside you'll notice that the Radiator/"Heating system" won't see Hot Coolant until it hits that T-Stat #. Then it'll start to melt the inch of ice off your windshield. Absolutely no coolant is leaving that block till you've reached that desired T-stat #!!!!

Right now you're keeping all that hot coolant inside your engine till it hits 195* then you're opening the system so that the radiator can cool the fluid and engine..... Obviously the Radiator/Cooling System is having a hard time and opening it late isn't helping.... but the Airdam will help!

I have a 160* thermostat.... Therefore the engine coolant heats up till 160* then the T-stat opens so that the rad can start cooling it (I drive aggressively)......
I never find that the car runs at 160* unless on the highway on a cold day.

jac113

iTrader: (4)

I get your point GTA sammy, I guess what i'm gettin' at is the fact that my car "SHOULD" be running at normal temps which i "guess" is 220 F or below. I don't want to run a lower T-stat in my car unless I absolutely have to plus the cooling system is not so complicated to where I have to compensate for something that can't be figured out. I have a new rad, cap, h20 pump, t-stat, fans work fine, new hoses, new head gaskets. There's no reason why I shouldn't be able to run a 195 T-stat, which is factory spec, unless my old cap was bad and the timing is so far off its causing overheating. The cap and timing are the only things I have going for me now. When I start it today i'll check to see if vapors are getting in coolant from maybe a crack in the block but when I was filling it up with coolant there were no more air bubbles.

i'll keep y'all posted. and about the air dam, I have not made it out of the neighborhood so with the car exceeding 220 at idle is strictly a cooling system problem.

astrosurfer

I disagree...
The pump will circulate engine water through your heater core even if the t-stat is still closed. Therefore you will get warmer air as the engine heats up.
When the t-stat opens it is to allow the water to flow through the radiator to cool it off.
You can start to defrost windows before the t-stat opens in any car I have ever owned.

avilla20

also the tstat starts to open 15-10 degrees before that magic number so fluid is leaving that block way before 180 or 190, that tstat number is the temp that the t stat will be fully open.

avilla20

how are you bleeding the air out, all this work and i havent read anything about bleeding the cooling system.

GTA Sammy

iTrader: (1)

Sorry I should never talk in absolutes.... There's no wiggle room...

But just outta curiosity..... how cold does it get in Louisiana??? Because I can tell you that in the 18 years of my driving experience and many different vehicles that you won't defrost thick iced windows till the T-stat hits that referenced Temp #. You can actually feel the heater core get hot coolant after the T-stat opens by what is blowing out!!!! Until that point of opening the air blows -40 cold

Just my

jac113

iTrader: (4)

Update: good news
I turn it over and let it idle for a couple minutes. Then I drive it down to a friends house a mile away to put the car on a scanner. He pulls out the scanner and timing light and wait about 10 mins until it gets to normal temp. We check the temp from computer(CTS) and compare to Gage and the Gage was behind about 20 degrees. The temp peaked at 222 when the fan came on it turned off at 214. when temp was at 222 the Gage was at the 3rd tick so about 240? It came back to normal after a while. It must be a bad contact because whn the coolant used to biol the Gage was near red. We check timing and I already had the timing at 6 btdc, timed it right by ear somehow.
As far as bleeding the system I would let it warm up with rad cap off. I have not driven it yet but I will once I put the air dam on. I hope to see cooler temps while driving.

So thanks guys for all the help. Now I can put the hood back on and put all my accessory brackets on.