Engine 89gt-overheating-questions

Discussion in 'Fox 5.0 Mustang Tech' started by stang89bidges, Mar 26, 2014.

  1. 1989 GT. Had the car 2 years now. DD. Replaced the heater coil when I bought it. Engine always ran cool with it's 180 degree thermostadt but heat worked well when car finally warmed up.

    4-5 weeks ago I started noticing when I would "get on her" a little here and there the engine was heating up more than normal. I also noticed a razorblade slice in my lower radiator hose after seeing my first leak on this mustang, replaced it. 2 weeks ago when I got on her a little and arrived home the engine had a boiling sound and antifreeze was spewing out of the radiator overfill tank somewhere.

    I replaced the thermostadt last weekend. Now it has a 190 degree thermostadt installed. I bought the newer lock-open thermostadt. Now the engine gets warmer and heats up in the morning much faster which is nice. But two nights ago, I got on her a little to test her out and got home to more water/antifreeze all over the ground boiling out the radiator overfill somewhere.

    When I replaced the thermo the water appeared a nice color green, not too dirty. A year ago I had drained the radiator and refilled with 50/50.

    The PO had an after market aluminum radiator installed. It's not a big one, it's skinny but same width/highth as stock. It still has original fan shrowd installed.

    It still has original water pump installed and mechanical fan. I have a new electric fan on the way now. I am wondering if you guys think it's the water pump? This car only has 77,000 original miles BTW. Most components on the engine are stock still.

    Mods include but not limited to:
    Vortec V2 SC
    Ford Racing Wires and Plugs
    Aluminum radiator
    BBK headers and flowmaster thunder exhaust system - X pipe

    As far as engine that's about it. I am assuming my water pump is going out. I don't see water leaking from engine or heads. It's only boiling out when I get hot and heavy on her. And it seems to be coming out somewhere from the overfill tank side of things.

    Another thing I wanted to mention is the overfill tank. It's super dirty. I dont see dirty water in the radiator cap, or when I changed the thermo, but that overfill plastic tank is super nasty. The tube with sensor is pretty bad. I wipe it off usually when I pull it out everytime but is this dirty because everything is plastic and it's attracting all the dirt and therefore keeping it out of the engine?

    Thanks in advance,
  2. Under the conditions that you describe, the electric fan isn't going to make lick of difference.

    You should be running at LEAST a two-core radiator with a power adder.

    Here's another wrinkle to consider:
    Your power adder may have blown a path to the cooling system. What head gaskets are you using? Was the car tuned for boost? By who?

    It may be time to pressurize your cooling system and check to see if there are any leaks. If you're getting combustion gases into the cooling tract then it's likely through a faulty head gasket and needs to be cured.
    Check your exhaust for any sign of coolant contamination as well as the coolant for any signs of other contamination (regardless of how small).
  3. I don't see any white smoke or sweet smell coming from exhaust. I don't see a white glaze or any contamination on oil filler cap or dip stick. I see where the water is coming out finally. There is a overflow outlet on the top of the overflow plastic tank. When engine water boils over into plastic tank and fills it up it shoots out.

    also, I noticed the car this morning heater didn't heat up. engine was warm but until I turned off the heater, waited a minute, turned heater back on, after a minute or so the heater started to blast hot air. Why did it take so long? Checked water level was just barely missing any water. And the whole turn off and back on again heater threw me for a loop. Water pump not pumping the hot water very well?
  4. i would think if everything is operating properly,worst case what noobz said,but maybe rad cap also?....the heater does that somtimes if there is air in the system ?...
  5. What do you mean by radiator cap? Can those leak or go bad or something? I don't think it's leaking because when it's boiled over liquid isn't coming from the cap it's coming from the overfill reservior.
  6. the rad cap has a spring in it and lets out at a certain pressure into the overflow....i had a car that had a bad cap and it gurgled after long drives.....changed the cap and good to go.....but you should pressure test you system cause a bad head gasket also causes that even with no white smoke,it can be from the exhaust side,and after a while it builds up in the system and lets go into the overflow....

    thats just with my experience though....much more knowledgable guys on here that im sure will chime in...
  7. How do I know if my aftermarket aluminum radiator is a 2 core radiator?
  8. Well I have bad news... I filled up my car 2 days ago with water and it seemed to be doing great. This morning after I got home I found a small puddle of water under the car again. I decided to go get a new radiator cap since it was a cheap investment.

    Bad news is I removed the radiator cap and noticed the water level was down a little but very dirty looking. I dunked my finger in the water and when I pulled it out my finger was coated in OIL!

    Does this mean my head gasket is blown?
  9. More than likely.
  10. Update. I still can't tell if it's my head gaskets or something else.

    2 weekends ago I changed the oil, flushed the cooling system, and ran pressure tests. Turned out my radiator cap was bad. So I replaced the cap. No coolant in the oil. No foam at the oil cap.

    The system was pretty dirty. I think it was just build up in the water overflow tank. It did smell a little bit like oil but I really couldn't tell.

    Cleaned this out with a brush and bleach cleaner:

    Here is what the water looked like coming out of the overflow tank:



    This is the paper towel I used to strain the water to look for large particles and oil residue:

    Large particles weren't bad:

    So after flushing the coolant system, refilling completely with water, then doing a pressure test it seemed to be ok. The tester said that it should take 2 minutes for the needle to start dropping in pressure. Mine starting dropping in about 1.5 minutes. That told me my pressure was pretty decent right?

    Well, I drained the radiator of water. Filled it back up with antifreeze. Got the new cap put on the radiator. Drove it for a week. Two things happened.

    1. I previously bought a "safe lock" thermostat. The kind that locks open when they stick. Well it's only 2 weeks old and it already stuck open. Is this by design? The last day I drove it before I did this flush it got up in temperature pretty high. Is this why it already failed and stuck open? So the mustang never got up to temp since this locked open during my first week of testing after the flush.

    2. It lost water. It took 5 days and just normal driving conditions but I lost about a half gallon in the system. Never saw any on the ground. But by Friday(flushed on Sunday), I was putting more water back into the radiator. Overflow was full.

    Also, here is a video of my car after I did the flush. There was a little water spraying out of the exhaust. Not dripping. Flying out in a bit of a mist. Got the ground wet. There is a puddle of water that already existed next to where the exhaust is spraying so pay no attention to that. I eventually point to the puddle coming out of the exhaust:
    ---You have to click on this picture to view video---
    View attachment 117278

    Edit: Man that high pressure fuel pump really whines doesn't it?

    So. This week I kept on driving the car after putting more water in the system. It seems to have done better but now I am noticing tiny little puddles of water under the car occasionally. Like 20 drips maybe. I just got home about 45 minutes ago. So after 45 minutes of sitting I checked the radiator. When I released the cap it had a lot of pressure in it. Started gurgling water and air into the overflow container.

    I looked at the overflow container and it was at the "FULL WHEN HOT" line. Radiator wasn't plum full but it wasn't missing too much water either. Is this a air pocket issue I have going on?

    Also, I reached down to the radiator cap and smelled and it smells like oil to me but again, not sure if its really just older smell with antifreeze. I don't know. Should it have a small trace of oil smell to it? Is this normal to kinda smell like oil?

    The water in the overflow is still really really clear. When I cleaned it out and filled the system back up with antifreeze I only put water back into the overfill container. It looks as though the new cap is working well but not letting any antifreeze from the radiator move into the overfill and visa versa. This would be a problem right? I read that the 89 mustang is a pressured system. So when you are running low on coolant you only fill the overflow as when the temp rises it floods water into the overfill tank, then when it cools it draws water back into the radiator.

    What do you guys think? Long post I'm sorry.
  11. no, man. i dont think thats how it works. When its low on coolant, you have to fill the radiator with 50/50 coolant and water to the top. forget the overflow tank for now. It should be empty. since you got air in the system from the hose or the thermostat change, you have to seal it all up except the radiator cap, fill the radiator, and then burp (squeeze hard over and over) on the radiator hoses to get air out, and then run the engine to suck the coolant into the system. when you start the motor you will see the coolant drop a little. top it off, watch it go down more, and top it off again until its full. Cap it when its full because its going to get HOT. Then fill the overflow tank to the cold line and youre good. Only if the temp. exceeds the standard of the rad. cap will coolant "overflow" into the dirty looking plastic tank. 50resto sells those pretty cheap, btw.

    Also... Your coolant looks super dirty and flushing it will not fix the cause of contamination. Thats a problem. Do the pressure check on your head gasket, because coolant should NOT smell like oil. nor should it look like pond water. It should be sweet smelling. Try smelling a fresh bottle of antifreeze for reference. That stuff needs to stay clean. You have to address the problem before patching the symptoms.

    1. your head gasket is probably broken.
    2. that original water pump has no business on a SC car.

    hope this helps.
    #11 OonDeanisS, Apr 11, 2014
    Last edited: Apr 11, 2014
  12. Oh man... That sucks. Car only has 70,000 original miles on it btw. Couple questions.

    1. I was going to replace the water pump tomorrow with a new electric fan I purchased. Proform from latemodelresto. Just found out the old fan shrowd won't go back on so that means the old overfill tank won't install back either. So now I got to get a new overfill tank. Do you think the OEM replacement water pump I got will be ok?

    2. If I get this think apart tomorrow and drain the radiator and find dirty water again I will know its the head gasket. What do you recommend doing while I replace head gasket?
  13. Stop. Before you do anything esle- go rent an exhaust gas coolant test kit from Autozone.

    Pray to the car gods the fluid doesn't turn green.

    If that checks out- rent the pressure tester. Test the cap- it should hold 16lb. Pressurize the system to 16lb. It should hold that for at least 1/2 hour. If it drops or you see leaks, then you have a problem.

    Run a cylinder balance test.

    If al checks out, flush out the system and repace with a 50/50 mix of old style green antifreeze and distilled water. Buy a Lisle fill kit to burp out all the air- you will thank me for it.

    As stated before, you need at least a 2 core alum radiator with a blower and a GOOD electric fan, shroud, and delflector.

    With any forced induction, you can run rich all day long, but lean once and detonation will blow a head gasket. IF you need to replace the gaskets, I recommend Felpro 9333 head gaskets and ARP head studs. You can reuse the studs over and over.
    Noobz347 likes this.
  14. you can use zip ties to secure the overflow tank. the oem water pump is good. double check that its the right one. some water pumps are reverse rotation. If you do the head gasket, replace ALL the gaskets you remove to the manufacturers spec. torques. Dont overtorque them. replace your PCV valve while you have the manifold off, and clean (with brake cleaner) or replace the filter beneath the pcv valve, and the rubber grommet around it.
  15. If it is the h/g, when you pull the heads off, after you clean off the deck surface and the heads, lay a straight edge on the deck and the heads and stick a feeler guage underneath. If the heads are a little warped no big deal as they can be easily milled by a machine shop, but if the deck is warped, then you got a problem. It will never seal unless it's milled. I doubt that's the case but it is worth checking before you start spending money on this.

    stang89bidges likes this.
  16. Great advice above :SN:
  17. Big update. Lots of pics.

    I drained the radiator after two weeks of driving. Looks clean.

    View attachment 117152

    View attachment 117153

    I decided not to pull the heads off just yet. Car runs great. Radiator still clean. Replaced radiator cap that failed. Going to replace thermostat and hoses. Replacing water pump. Oh, water pump, look what I found when I removed the radiator and the lower radiator hose:

    View attachment 117154

    View attachment 117155

    View attachment 117156

    What the hell does that spring go to? That end was connected to the water pump...

    View attachment 117157

    Still supporting the original water pump.

    View attachment 117158

    View attachment 117159

    So what do you guys think about this radiator? Is it a 2 core? 3 core? It's awful skinny.

    View attachment 117160

    View attachment 117161

    View attachment 117162

    View attachment 117163
  18. Spring keeps the hose from collapsing under pressure.
  19. yep on spring, it should not enter the pump it would jam the impeller....

    that rad has to be one core, mines 2 and it fills the whole section of the side sections where yours has that ridgey section behind the fins...
  20. That is my second lower radiator hose. I'm assuming its toast now because that spring came loose?

    Where can I get a good quality hose?