Major overheating problem....coolant resevoir cap blew off today (long)....
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Joined: Jul 2000
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From: Central Mass
Major overheating problem....coolant resevoir cap blew off today (long)....
Hi guys,
Had a nasty problem today when firing up the firebird (87 Formula, LG4 5spd) for the first time in 4 months today. Changed the oil, checked the fluids and the radiator was filled to the top and looked clean (but the coolant overflow resevoir was pretty much empty). The car started up after charging the dead battery, and idled at 1000 rpm for several minutes..then it kicked itself up to about 1600 rpm. I let it idle that way for about 10 minutes, watching the car from the a distance, and it was idling normally. All the while I'm pretty sure the electric fans never kicked on (didn't realize this at the time...STUPID!). It was 45 degrees here in MA, not warm at all, with a breeze. My dad got in the car and took it for a ride up and down the street, a whole couple hundred feet, and when he came back smoke was POURING out of the car's hood...and liquid was splashing out of the hood/fender joints. I shut the car off immediately, and when we mananged to open the hood the coolant was spewing like a geyser for about half a minute out of the coolant resevoir, the cap was halfway down the street, and apparently the temp. gauge was pegged at 260...the whole time I never saw the electric fans on, while it was doing this or before, with or without the car on... I'm pretty sure that's the problem.
Also, I'd like to mention that the previous owner disconnected the heater core, and the hose going into it is at a 90 degree angle clamped to another hose (the return hose I'd assume). My dad thought that would be the problem and it would restrict the flow and build up pressure. (the car never overheated so badly though this past summer when I drove in 80 degree+ weather, but was always near 220). Could this have something to do with it as well, and what could we do to fix it?
Guess the main question I'm asking is what should I do about this whole problem, cleaning it up (spewed all over the right half of the engine compartment) and figuring out what went wrong here? I'm guessing it might be the coolant temp. sensor? I have a feeling it wasn't working and therefore it didn't turn the fans on. God I hope it didn't do any permanent damage. Thanks for your help guys,
Steve
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87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
Had a nasty problem today when firing up the firebird (87 Formula, LG4 5spd) for the first time in 4 months today. Changed the oil, checked the fluids and the radiator was filled to the top and looked clean (but the coolant overflow resevoir was pretty much empty). The car started up after charging the dead battery, and idled at 1000 rpm for several minutes..then it kicked itself up to about 1600 rpm. I let it idle that way for about 10 minutes, watching the car from the a distance, and it was idling normally. All the while I'm pretty sure the electric fans never kicked on (didn't realize this at the time...STUPID!). It was 45 degrees here in MA, not warm at all, with a breeze. My dad got in the car and took it for a ride up and down the street, a whole couple hundred feet, and when he came back smoke was POURING out of the car's hood...and liquid was splashing out of the hood/fender joints. I shut the car off immediately, and when we mananged to open the hood the coolant was spewing like a geyser for about half a minute out of the coolant resevoir, the cap was halfway down the street, and apparently the temp. gauge was pegged at 260...the whole time I never saw the electric fans on, while it was doing this or before, with or without the car on... I'm pretty sure that's the problem.
Also, I'd like to mention that the previous owner disconnected the heater core, and the hose going into it is at a 90 degree angle clamped to another hose (the return hose I'd assume). My dad thought that would be the problem and it would restrict the flow and build up pressure. (the car never overheated so badly though this past summer when I drove in 80 degree+ weather, but was always near 220). Could this have something to do with it as well, and what could we do to fix it?
Guess the main question I'm asking is what should I do about this whole problem, cleaning it up (spewed all over the right half of the engine compartment) and figuring out what went wrong here? I'm guessing it might be the coolant temp. sensor? I have a feeling it wasn't working and therefore it didn't turn the fans on. God I hope it didn't do any permanent damage. Thanks for your help guys,
Steve
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87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
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87,
This is an excellent opportunity to replace the suspect thermostat.
Clean and flush the system. Install a new thermostat and gasket. Refill the system with a fresh coolant mix and start the engine. Check for leaks.
Monitor the level after several heat/cool cycles to refill from any entrapped air that has escaped the system.
The heater core bypass should not be causing a problem as long as no hoses are kinked closed.
You should also check the other hoses, especially the lower radiator hose for collapsing at higher RPMS.
The cooling fans may not have operated because the sensors were not immersed in coolant, so they could not sense the engine temperature.
Cleaning up that sticky old antifreeze is fun, isn't it? Incidentally, keep your pets away from the coolant. Antedote doses are about $560.00 each, and my dog needed two of them. I could have had a new torque converter and a nice pair of coated headers for what that cost me...
------------------
Later,
Vader
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"I'm'a do Things My Way - It's My way or the Highway."
Adobe Acrobat Reader
This is an excellent opportunity to replace the suspect thermostat.
Clean and flush the system. Install a new thermostat and gasket. Refill the system with a fresh coolant mix and start the engine. Check for leaks.
Monitor the level after several heat/cool cycles to refill from any entrapped air that has escaped the system.
The heater core bypass should not be causing a problem as long as no hoses are kinked closed.
You should also check the other hoses, especially the lower radiator hose for collapsing at higher RPMS.
The cooling fans may not have operated because the sensors were not immersed in coolant, so they could not sense the engine temperature.
Cleaning up that sticky old antifreeze is fun, isn't it? Incidentally, keep your pets away from the coolant. Antedote doses are about $560.00 each, and my dog needed two of them. I could have had a new torque converter and a nice pair of coated headers for what that cost me...
------------------
Later,
Vader
------------------
"I'm'a do Things My Way - It's My way or the Highway."
Adobe Acrobat Reader
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Joined: Jul 2000
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From: Central Mass
Thanks for the reply Vader. We changed the thermostat today, and flushed the cooling system several times today...the car still was climbing towards 260 degrees though with no sign of letting up. The fan never came on the whole time, and after talking to a mechanic, he told us it is probably the cooling fan switch. Also, we ran the AC and the fan did kick on with no problem, so we know the fan isn't dead. Also, the check engine light hasn't gone on and the car seems to be running decently...so that probably means the ECM and Coolant Temperature Sensor are ok, right?
My current Problem is, when we yanked out what we *thought* was the cooling switch and brought it to auto zone and they gave us the new part, it looked nothing like the device we had (a bolt with 2 prongs on the end, and this one we took out screws right into the top of thermostat housing and has a dark green wire and black wire running into it). According to my chilton's manual, this is the cooling fan switch, but the replacement part from auto zone basically is a completely different part. (bolt with one tube-like tip) Can anyone tell me what this part will look like, WHERE it will be on the engine, and what color wires run into it? I'm really scratching my head at this point
Also, if you don't think this is the problem, feel free to say so. Thanks in advance,
Steve
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87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
My current Problem is, when we yanked out what we *thought* was the cooling switch and brought it to auto zone and they gave us the new part, it looked nothing like the device we had (a bolt with 2 prongs on the end, and this one we took out screws right into the top of thermostat housing and has a dark green wire and black wire running into it). According to my chilton's manual, this is the cooling fan switch, but the replacement part from auto zone basically is a completely different part. (bolt with one tube-like tip) Can anyone tell me what this part will look like, WHERE it will be on the engine, and what color wires run into it? I'm really scratching my head at this point
Also, if you don't think this is the problem, feel free to say so. Thanks in advance, Steve
------------------
87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
Junior Member
Joined: Jan 2001
Posts: 91
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From: VA
You ought to check the codes while your at it. What tempature stat did you use? Did it overheat while idling or driving after you changed the stat?
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1985 TransAm BLK/GLD Stock
1985 TransAm BLK/BLK
305HO (soon as it is put in) 5-speed, 3.27 posi, WS6, power everthing.
http://www.geocities.com/bullfrawgs
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1985 TransAm BLK/GLD Stock
1985 TransAm BLK/BLK
305HO (soon as it is put in) 5-speed, 3.27 posi, WS6, power everthing.
http://www.geocities.com/bullfrawgs
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Joined: Jul 1999
Posts: 18,457
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
The temp switch that turns the fan on is in the pass side head, between the #6 and #8 spark plugs. It has a single pin round Weatherpack connector.
The ECM doesn't control the fan in that setup. The things on the water outlet have nothing to do with it. There should be 2 objects there: the thermal vacuum switch for the EGR, and the ECM's coolant temp sensor.
You can take the wire off of the fan switch and ground it with the key on, and it should make the fan come on. If it doesn't, check the fan relay, which is between the master cylinder and the left fender, it has a plug with 2 small wires and 2 big ones, one red and one black. It should click when you ground the temp switch wire, and should put 12V on the fat black wire. If it does, you probably need a fan motor.
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"So many Mustangs, so little time..."
ICON Motorsports
The ECM doesn't control the fan in that setup. The things on the water outlet have nothing to do with it. There should be 2 objects there: the thermal vacuum switch for the EGR, and the ECM's coolant temp sensor.
You can take the wire off of the fan switch and ground it with the key on, and it should make the fan come on. If it doesn't, check the fan relay, which is between the master cylinder and the left fender, it has a plug with 2 small wires and 2 big ones, one red and one black. It should click when you ground the temp switch wire, and should put 12V on the fat black wire. If it does, you probably need a fan motor.
------------------
"So many Mustangs, so little time..."
ICON Motorsports
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Joined: Jul 2000
Posts: 29
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From: Central Mass
Wow, now I'm really confused Today I had to order a part from the local Chevy dealer, it's Part # 25037089 "Engine Coolant Blower Switch" and they took note of the fact that I had a manual transmission, and they said that this switch would control the fan. It has 2 prongs on it which connect to the wiring harness/connector, and they said the other end bolts into the thermostat housing above the water pump. (just like what we took out yesterday which according to this manual is the cooling fan switch) They had to have the part shipped from Lansing, MI so I guess it's a pretty specific part. But RB you say it plugs into the cylinder head on the passenger side?? Yikes, that's not even near this switch that we found. The wiring diagrams in the chiltons manual said this switch had a dark green wire and black wire running into it...only thing I switch I found with that was this two pronged item. does anyone know what color wires run into the switch that's on the cylinder head? (I dont have access to the car, it's stored across the city and I can't get to it for a couple of days). If anyone else can shed some more light on this, I'd appreciate it, thanks everyone for your help so far
Steve
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87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
Today I had to order a part from the local Chevy dealer, it's Part # 25037089 "Engine Coolant Blower Switch" and they took note of the fact that I had a manual transmission, and they said that this switch would control the fan. It has 2 prongs on it which connect to the wiring harness/connector, and they said the other end bolts into the thermostat housing above the water pump. (just like what we took out yesterday which according to this manual is the cooling fan switch) They had to have the part shipped from Lansing, MI so I guess it's a pretty specific part. But RB you say it plugs into the cylinder head on the passenger side?? Yikes, that's not even near this switch that we found. The wiring diagrams in the chiltons manual said this switch had a dark green wire and black wire running into it...only thing I switch I found with that was this two pronged item. does anyone know what color wires run into the switch that's on the cylinder head? (I dont have access to the car, it's stored across the city and I can't get to it for a couple of days). If anyone else can shed some more light on this, I'd appreciate it, thanks everyone for your help so farSteve
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87 Formula Firebird - LG4, 5 spd, All Stock!
84 Delta 88 Royale Brougham
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