over heating
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over heating
i'm having a problem with overheating, i have by-passed the throttle body by running one heater hose directly to the front of the intake and the other directly to the water pump. i am running vortec heads and a scoggin-dickey intake manifold for tpi. i realize that the anwser is something very obvious, i'm stumped right now, i think that i have been looking at it too long :cheers:
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Re: over heating (atotalnincompoop)
What are your temps? coolant and oil.
That Temp tstat are you running, how long has it been since you cleaned the front of your radiator.
That Temp tstat are you running, how long has it been since you cleaned the front of your radiator.
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Re: over heating (vader86)
i'm running a 160* stat and the rad is very clean, the problem is there even when i remove the thermostat. i flushed water through the heater core to eliminate an air lock, it runs for a few minutes and then i get the vulcano out the rad cap
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Re: over heating (atotalnincompoop)
as far as the temps go, i don't have the number in front of me right now and i was out of town for a week but i think that they were above the boiling point for water, the oil i don't remember
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Re: over heating (C4-Wolf)
i'll go check that this evening, i think you may be correct. thanks i'l get back to you, my biggest fear was that it was something to do with the heads and that i possibly used the wrong head gasket and blocked off a water passage, does anything like that sound familiar :cheers:
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Re: over heating (atotalnincompoop)
What engine is this?.........as far as water pumps...... they will pump and pump......... the only thing they do wrong is leak or the bearing will go out. The metal impeller will keep pumping though. I ask what engine because as you said it could be heads or a passage........like a 400 block with 350 heads ........ya have to drill the steam holes in the heads..........need more info :seeya
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Re: over heating (vettmech)
Had this problem in my '85 (oflow tank puking out all the coolant). 2 things fixed it. Gasket was bad in the oflow tank cap, and the radiator cap was bad. Fixed the cap, and got the correct 17lb cap from the general. Voila, problem gone. And it gets tested a lot here in Vegas.
:mad :flag
:mad :flag
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Re: over heating (atotalnincompoop)
The pressurized coolant in the engine won't boil until over 250* F, it will lower to around 220 (50% H2O) if the system does not hold pressure. Is the cap any good, does it seal, do you have coolant leaks?
If you are blowing coolant out the cap in only a few minutes of running (does the fan come on?) you have issues. I would pressure check the cooling system and perhaps run a compression check. How does the oil look?
It's quite normal for these engines to run over 220*.
If you are blowing coolant out the cap in only a few minutes of running (does the fan come on?) you have issues. I would pressure check the cooling system and perhaps run a compression check. How does the oil look?
It's quite normal for these engines to run over 220*.
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Re: over heating (PeteL)
its a 350 block ( '85) with '98 350 vortec heads, it boils over with the system unpressurized( no cap on) . does anyone know if the water passages all line up, i have never read anything about them not, but i suspect that this may have something to do with it :cheers:
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Re: over heating (atotalnincompoop)
:cheers: I may be all wet, but how did you do the throttle body by pass?
I've done mine and never chasnged the direction or connection of the heater hoses, just put a nipple in to connect the inlet and outlet hoses from the throttlebody.
Like I said, I may be all wet, but i would look again at the heater hose set up
Jack
I've done mine and never chasnged the direction or connection of the heater hoses, just put a nipple in to connect the inlet and outlet hoses from the throttlebody.
Like I said, I may be all wet, but i would look again at the heater hose set up
Jack
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Re: over heating (jackdaroofer)
well, i think that i have that right, the hose from the upper heater hose connection runs to the intake and the lower cinnection to the water pump. i put new hoses the proper length on instead of splicing together the old ones. do you think that i have something backwards here? :confused:
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Re: over heating (atotalnincompoop)
Let's hope none of these symptoms exist:
Is there pressure in the system when you remove the rad. cap with a cold engine?
Is the rad. low on coolant after cooling down?
Is the overflow bottle full with a cold engine?
Does your coolant "bubble" (not boil) with the rad. cap off, and the engine running?
If so, you may have a small exhaust head gasket leak into your coolant system.
[Modified by Oldman, 8:06 PM 9/30/2002]
[Modified by Oldman, 8:11 PM 9/30/2002]
Is there pressure in the system when you remove the rad. cap with a cold engine?
Is the rad. low on coolant after cooling down?
Is the overflow bottle full with a cold engine?
Does your coolant "bubble" (not boil) with the rad. cap off, and the engine running?
If so, you may have a small exhaust head gasket leak into your coolant system.
[Modified by Oldman, 8:06 PM 9/30/2002]
[Modified by Oldman, 8:11 PM 9/30/2002]
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Re: over heating (atotalnincompoop)
i'm starting to think that maybe i'm really stupid. 
i have made my own throttle body by-pass simply by routing a new piece of hose from the front of the intake to the heater core metal line. the other heater core metal line is then connected to the water pump. I'm sorry to have to ask this but is this routing correct? i obviously have some sort of coolant flow problem which may still be an air lock. i'm just wondering if i have something hooked up backwards which is causing all of my problems. thanks again guys :cheers:
i have made my own throttle body by-pass simply by routing a new piece of hose from the front of the intake to the heater core metal line. the other heater core metal line is then connected to the water pump. I'm sorry to have to ask this but is this routing correct? i obviously have some sort of coolant flow problem which may still be an air lock. i'm just wondering if i have something hooked up backwards which is causing all of my problems. thanks again guys :cheers: