Overheating or something more?
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Intermediate
Joined: Jun 2005
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Overheating or something more?
Last week I was going to take out the 75 vette (350 small block) for a nice 3-4 hour drive. I let it idling in the garage and after about 15 minutes I backed up to my driveway. I ran back into the house to get some thing, and when I get back in I saw stream/smoke coming from the hood. Maybe 20-25 min max time mostly idling.
I shut off the vette and open the hood the radiator overfill tank was boiling and antifreeze was coming out from the side of the tank.
I ended up pushing the car back into the garage, I didn't want to overheat it, and unfortunately I didn't look at the temp gauge.
Since then I refilled the radiator, and started it up and let it idle for a while, I saw the temp gauge go to almost 200 but what I'm worried about is that the fan pack never turned on.
My question to you all, is this a thermostat or a electrical to the fans issue? Where should I start the trouble shooting.
-turtlerok
I shut off the vette and open the hood the radiator overfill tank was boiling and antifreeze was coming out from the side of the tank.
I ended up pushing the car back into the garage, I didn't want to overheat it, and unfortunately I didn't look at the temp gauge.
Since then I refilled the radiator, and started it up and let it idle for a while, I saw the temp gauge go to almost 200 but what I'm worried about is that the fan pack never turned on.
My question to you all, is this a thermostat or a electrical to the fans issue? Where should I start the trouble shooting.
-turtlerok
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
No evidence of leaks?..and oil's not milky,..correct?
Do you have aftermarket elect. fans?...explain the set up.
Might try a new thermostat (cheap and easy) then my second troubleshooting effort would be to check for a clogged radiator,..clogged with slag and rust from the motor. Might try a flush with a reverse flush kit (your parts counter has one,..$12) If that doesn't cool it, take the radiator to radiator shop and have it checked out.
If a previous Bubba-owner had ever used one of those 'miracle-in-a-bottle' "stop-leak" products, they too will clog up flow in the radiator.
Do you have aftermarket elect. fans?...explain the set up.
Might try a new thermostat (cheap and easy) then my second troubleshooting effort would be to check for a clogged radiator,..clogged with slag and rust from the motor. Might try a flush with a reverse flush kit (your parts counter has one,..$12) If that doesn't cool it, take the radiator to radiator shop and have it checked out.
If a previous Bubba-owner had ever used one of those 'miracle-in-a-bottle' "stop-leak" products, they too will clog up flow in the radiator.
Burning Brakes
Joined: Jan 2006
Posts: 876
Likes: 1
From: Same as our leaders Out of my mind
It sounds like it is time for some minor maintenance. I would start with inspecting the radiator cap seal and possibly the spring as well. The caps go bad, seals and springs wear out and allow coolant to escape long before it should. Next I would fill the radiator, leave the radiator cap off, start the car, let it warm up and see if you can see coolant "flowing" in the radiator when the temp gauge is at the 190* - 200* range. If you see good coolant flow, then the thermostat is OK and water pump too. It is possible that the thermostat is also worn out/malfunctioning. These are low cost, easy to replace items and a good place to start.
My .02
My .02
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The fan pack is after market. Heres the wierd thing. I started it up over the weekend and it was running what seemed like 30 minutes without it getting close to 200, maybe like 190.
I just started the vette up like 20 minutes ago and in 5-10 min it was well over 210. The needle was past the 00 in 200.
Does this seem to point to a faulty themostat? I had this car over a year and though a Georgia summer, so this is the first time I had this sort of issue.
Answer me this, when does the fans know when to turn on? By the themostat? It seems to heat up a little too quick even without the fans going.... maybe the suggestion of replacement themostat is a better way to start.
I just started the vette up like 20 minutes ago and in 5-10 min it was well over 210. The needle was past the 00 in 200.
Does this seem to point to a faulty themostat? I had this car over a year and though a Georgia summer, so this is the first time I had this sort of issue.
Answer me this, when does the fans know when to turn on? By the themostat? It seems to heat up a little too quick even without the fans going.... maybe the suggestion of replacement themostat is a better way to start.
Burning Brakes
Joined: Jan 2006
Posts: 876
Likes: 1
From: Same as our leaders Out of my mind
Sounds like low coolant level or air in the cooling system. The fan sensor switch is either on the gooseneck on the intake manifold or in the side of one of the heads. If there is no coolant going past the sensor - it won't see anything, plus low coolant levels leads t fast overheating. You also need to check your oil level. The oil and the coolant work side by side to keep your engine cool.
Thread Starter
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I took the cap off, it was about .5 to an inch from the top. I started the engine and the coolate in the radiator dropped a few inches at least. I shut off the engine and the coolate went back up to where it was. I then filled it to cap it off and started the engine. It dropped again a few inches. I'm now letting it idle up well see what happens when we hit that magic temp of 190-200.
The oil level is just a hair under FULL.
Question... When the coolate level drop when the engine is running means that the water pump is good?
Thanks,
The oil level is just a hair under FULL.
Question... When the coolate level drop when the engine is running means that the water pump is good?
Thanks,
Thread Starter
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Okay I was watching it and I think I'm getting closer. I saw fluid flowing in the radiator. The only thing missing was the fans were not spinning. Now the big question where do I begin testing the fans?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Do you have one fan or two? By this I mean do you only have an electric fan on the rad or an electric fan on the rad and one on the engine?
If you only have an electric fan on the rad follow the wires to the switch on the block. It will be in one of the heads near the manifolds...actually if its after market it could be just about anywhere. The sensor sometimes goes. You may also just have a blown fuse. Or it could be the wiring. Shouldn't be too hard to figure out.
If you have a fan on the motor and an electric fan on the rad. The electric is usually secondary and does no kick in until higher temps. If you have this combination of fans you have other problems.
Jim
If you only have an electric fan on the rad follow the wires to the switch on the block. It will be in one of the heads near the manifolds...actually if its after market it could be just about anywhere. The sensor sometimes goes. You may also just have a blown fuse. Or it could be the wiring. Shouldn't be too hard to figure out.
If you have a fan on the motor and an electric fan on the rad. The electric is usually secondary and does no kick in until higher temps. If you have this combination of fans you have other problems.
Jim
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From: Southbound
Cruise-In II Veteran
Originally Posted by 73, Dark Blue 454
....Might try a new thermostat....
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My configuration is a dual fan pack bolted right onto the radiator. I follow the sensers, it looks like I have 3 relays, one for each fan and one where I think either the main power or the temp senser attaches (not sure). Is there a way I can bypass the replay? I hear of talk of guy making a manuel switch for just that propose.
Would the themostat still be something to check into to, since I saw coolate running in the radiator.
turtlerok
Would the themostat still be something to check into to, since I saw coolate running in the radiator.
turtlerok