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Overheating and charging issues :(

  • Thread starter Thread starter 94GTMustang5.0
  • Start date Start date Aug 10, 2010
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94GTMustang5.0

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#1
  • Aug 10, 2010
  • #1
89 LX 5.0 5-speed

charging issue

alternator went out in my car, purchased a brand new alternator from an 89 t-bird from a friend, fits correctly and connects right up. 75 amp like the stock replacement. battery now charges, but the volt gauge stays just above the first white line above red. car will shut off and start repeatedly with no issue, but the AMP light is still very dimly lit. should i remove the alternator and have it tested again? tested fine before installation. checked battery cables and connections

Overheating issue

car was running hot (3/4 on temp gauge). Replaced cracked and leaking lower radiator hose. in the process of draining cooling system, i noticed the coolant was rust orange and had small brown fibers floating around. I immediately recognized the color and smell as STOP-LEAK. Flushed system, replaced hose, filled cooling system 100% with distilled water.

It reaches operating temp after driving around the block a few times, but once it goes over half on the gauge it keeps climbing until resting at 3/4. it wont get any higher but wont go down at all. I hear a hissing sound coming from what i think is the radiator. I flushed the system again and was greeted with the same rust orange colored coolant, but not as orange and no fibers. now i know why the whole bottom part of the motor is covered in rust orange dust ****. no smoke from exhaust which i heard is an indication of a bad head gasket.

P.S. radiator gets HOT AS HELL. apparantly unusually hot froim what a friend tells me

Car runs strong as hell, idles perfectly fine. any solutions/tests i can perform to find the cause of these problems?
 
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94GTMustang5.0

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#2
  • Aug 10, 2010
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also, when i spin the fan by hand there is a good amount of resistance but its not hard to turn, am i correct in thinking that the clutch is good?
 
B

BYRDPE

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Aug 10, 2010
#3
  • Aug 10, 2010
  • #3
i'd at least have a shop pressure check the radiator. if it's the stocker i probably wouldn't bother...just replace it.
how old is your battery? did you have it charged at the same time you replaced the alternator?
 
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94GTMustang5.0

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  • Aug 10, 2010
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the battery is of unknown age (no stickers except for energizer, brand of battery)

i jump started the car after putting the new alternator in.

will shops pressure check radiators for free?
 

1993SSP

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Aug 10, 2010
#5
  • Aug 10, 2010
  • #5
The fact that you think it has stop leak in it is enough for me to say ditch the radiator. I would replace the cap while I was at it. I'd take the battery in and have it tested, would definitley charge it overnight at least. The alternator is designed to maintain the battery, not completely recharge it.
 
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94GTMustang5.0

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  • Aug 10, 2010
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where can i get a good radiator for cheap? im about to start college and i got 300$ in books to purchase =/

should i buy a new cap and thermostat and install them and see if it helps? they are probably bad because of the stop-leak.

and trust me i know stop leak when i see/smell it. i put about 3 bottles of that stuff in my moms taurus to try and fix a radiator leak before i knew anything about cars.
 
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93GtMustang50

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Jul 23, 2009
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Aug 10, 2010
#7
  • Aug 10, 2010
  • #7
look on Mustang Parts, Chevy Truck Parts & Dodge Challenger Parts at Latemodel Restoration Supply they have good prices on equipment for your car.

the battery could be bad, a test at advanced will tell you if its good/bad.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Aug 11, 2010
#8
  • Aug 11, 2010
  • #8
Find a DMM and check actual voltage. The stock guage is not intended for diagnostics. Or have a parts store dynamically test the charging system. It's free at most places.

Does the alt light come on bright when you turn the key on (but before starting the car)? Or is it always the same amount of dim?

You might wanna get a real means of testing the cooling system temperature to really know what's going on there too.

Some of the online vendors have relatively cheap radiators. If you're going to keep the car, I'd go for a locally-purchased lifetime warranty one if you're getting a stock replacement or a 3 row unit.
 
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94GTMustang5.0

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#9
  • Aug 14, 2010
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HISSIN50 said:
Does the alt light come on bright when you turn the key on (but before starting the car)? Or is it always the same amount of dim?
Click to expand...

the battery light comes on when the key is on before starting, after i start the car it dims a little bit, then as a drive the car sometimes it will go away, then come back a little bit, then go away again.

P.S. I put the battery in my 94 and the volt gauge was reading perfectly fine. car will start repeatedly with the battery from the 89, so im guessing the battery is good.
 

HISSIN50

"How long does it take to get help in here?
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#10
  • Aug 15, 2010
  • #10
How was system voltage? Sounds like you might have a bad regulator.
 

ID89GT

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May 26, 2008
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Aug 15, 2010
#11
  • Aug 15, 2010
  • #11
I know this may be a dumb question, but when you filled the cooling system you say you filled it 100% with distilled water. Did you put any actual antifreeze in with the water?
 
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94GTMustang5.0

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#12
  • Aug 16, 2010
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No, i did not fill it with any antifreeze. 100% distilled water. i think i may have a leak somewhere so i did not waste any antifreeze on it.

where can i get a pressure tester for the cooling system? i checked advance auto parts and they told me they dont have it as a loaner tool
 
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94GTMustang5.0

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#13
  • Aug 17, 2010
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UPDATE: I had both the alternator and battery tested at autozone and both tested perfect. Now WTF? I read in a haynes manual about fusible links that can burn up and need to be changed. where are these located and what do they look like? Could they even be the problem?


P.S. Let this be an example to everybody, to not let AAA hook the jump box up to your car.
 

HISSIN50

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#14
  • Aug 17, 2010
  • #14
Did you ever test system voltage on the car?

How about testing the regulator wires (labeled A, S, and I on the reg itself)?
 
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94GTMustang5.0

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#15
  • Aug 17, 2010
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i replaced the fusible link from the orange/black wire that ties to the dark green right before the starter relay and it fixed the charging issue. Everything works fine now!

but now, onto the cooling system issue....

radiator is leaking on passenger side about half way down below the upper radiator hose. I also noticed something strange about the car..

if i fill it to the top with coolant and start the car, coolant spills out of the radiator neck like there is air in the system and it is bubbling out. I tried putting 3 different radiator caps on and coolant still leaks from below the cap when installed. this issue is frustrating me. is the radiator clogged and there is alot of pressure? help me please
 
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94GTMustang5.0

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Aug 18, 2010
#16
  • Aug 18, 2010
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bump. I start school aug 23rd and if this thing doesnt get fixed im taking the bus to school
 
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94GTMustang5.0

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Aug 19, 2010
#17
  • Aug 19, 2010
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update:

I drained the oil, no signs of coolant whatsoever. Just some super black oil.

Is there a detailed write-up of how to change the thermostat?
My haynes manual says to remove the cap and rotor to access the removal screws for the "diaphram" for the distributor, but i have no idea what this is.
 

fiveohwblow

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Jul 21, 2005
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#18
  • Aug 19, 2010
  • #18
Thermostat Install - StangNet - Promoting the Legend of the Ford Mustang
 
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94GTMustang5.0

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#19
  • Aug 19, 2010
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that write-up doesnt say anything about removal of the diaphram, and i cant get to the drivers side bolt =/

i tried a wrench but that plastic thing where the wires go into the distributor is blocking me!
 
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94GTMustang5.0

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Aug 20, 2010
#20
  • Aug 20, 2010
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UPDATE: Flushed the ENTIRE cooling system. Removed old, crusty thermostat (160 degree as distinguished by the markings) and replaced with a STANT 180 degree superstat.

I jacked up the front of the car to burp the system, and car ran perfectly fine. Thermostat opened and closed on time, went to 1/2 of the gauge and opened, gauge dropped to 1/4 then went back to 1/2, then dropped, etc. Process was repeated many times.

BUT, as soon as i drive the car, even slowly @ less than 20 mph, the temp will stay below 1/2, then sit at 1/2 for a few minutes, then climb to 3/4 and just stay there the entire time.

Now the issue that i dont understand, is why coolant is pouring out of the radiator. Even with the car in the air, when i fill the radiator and run the car, the coolant overflows the radiator neck (with the cap off) and pours onto the ground. If i increase engine RPM, it gets even worse and it pushes out a ton of coolant. If i put the cap on, it pushes the coolant right past the cap and leaks out everywhere, causing a terrible hissing sound while i drive

The engine oil has no coolant in it, the car runs perfectly fine, and temps wont rise as long as im not actually driving the car and it just idles in the driveway. But as soon as i drive it, it overheats, and there is a ton of pressure in the system apparantly.

The passenger side of the radiator is rusted and leaking, but not alot.

If I cant solve this issue, im selling the car.

EDIT: I used a 180 degree thermostat, not 195
 
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