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Cooling issues. Help needed!

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Old Nov 7, 2011 | 09:23 AM
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Default Cooling issues. Help needed!

Ok here is the breakdown:
car has been sitting for the past 2 years, last set of heads were leaking so heads were removed and decked, then reinstalled. Now while trying to bleed the system of any air, coolant will spew out of the overflow. No coolant is dripping out of the bleed tube. Im a bit lost as to where to pursue this problem next. Heads were installed to spec with all oem hardware.
also:
New thermostat
New Water pump

suggestions would be greatly appreciated! Thanks!
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Old Nov 7, 2011 | 01:02 PM
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I would try a coolant system pressure check. Oil look ok?
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Old Nov 7, 2011 | 01:08 PM
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Originally Posted by 01ssreda4
I would try a coolant system pressure check. Oil look ok?
oil looks fine, trying to borrow a set up from my friend to check system pressure tonight.
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Old Nov 7, 2011 | 01:10 PM
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also, car doesnt overheat when it starts spewing coolant.. temp gauge sits at 210 (yes i know theyre horribly inaccurate) but it did creep over once and only once when we first started the car due to there being not enough coolant at the time. but since then temp reads normal and coolant spews from overflow after it heats up.
internals of thermostat (although new) were taken out as a measure to make sure it wasnt sticking, but same thing happens every time, so internals were put back in to it.
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Old Nov 7, 2011 | 03:41 PM
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double checked oil.. its fine
pulled the radiator and found chunks of some sorta build up coming out while running fluid thru it.. new radiator will be here shortly, hopefully solves the problem..
any suggestions/input still greatly appreciated.
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Old Nov 7, 2011 | 04:46 PM
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Originally Posted by superchannelkev
also, car doesnt overheat when it starts spewing coolant.. temp gauge sits at 210 (yes i know theyre horribly inaccurate) but it did creep over once and only once when we first started the car due to there being not enough coolant at the time. but since then temp reads normal and coolant spews from overflow after it heats up.
internals of thermostat (although new) were taken out as a measure to make sure it wasnt sticking, but same thing happens every time, so internals were put back in to it.
Either you have the cross-over tube connected to the wrong port at the radiator fill neck.....((make sure the overflow line is on the UPPER port))....and when pressure builds it blows coolant right into the overflow tank.....

OR....you could have such a bad radiator cap, that when pressure builds up its blowing right into the overflow tank......

Or...sorry to say.....one of your pistons is pushing air into the cooling system. Maybe a bad install of one of the head gaskets......

.
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Old Nov 7, 2011 | 04:53 PM
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Originally Posted by LS6427
Either you have the cross-over tube connected to the wrong port at the radiator fill neck.....((make sure the overflow line is on the UPPER port))....and when pressure builds it blows coolant right into the overflow tank.....

OR....you could have such a bad radiator cap, that when pressure builds up its blowing right into the overflow tank......

Or...sorry to say.....one of your pistons is pushing air into the cooling system. Maybe a bad install of one of the head gaskets......

.
ill double check the overflow tube, im fairly sure its in the right spot though.
the radiator cap was just replaced, so that should be good.

and this isnt the first time ive done heads, and zero issues in all past installs so i surely hope this isnt the case, but true its always a possibility.

Appreciate the input!
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Old Nov 7, 2011 | 05:10 PM
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Originally Posted by superchannelkev
ill double check the overflow tube, im fairly sure its in the right spot though.
the radiator cap was just replaced, so that should be good.

and this isnt the first time ive done heads, and zero issues in all past installs so i surely hope this isnt the case, but true its always a possibility.

Appreciate the input!
There's only one way to make coolant either boil over (through the overflow tank) and/or have coolant spitting out of the overflow tank....

Air is getting into the system.........

And you said its happening with the t-stat "removed".......which means there's definitely no air pocket in there.

Coolant system pressure check is the key.......

***But....I would take all 8 spark plugs out if you do that. Because if you fill a cylinder with coolant, via a small or large leak in the gasket(s), and THEN go to start the engine....hydralock can literally destroy the engine in one second.

I would have a person on each side of the engine with flashlights while doing the pressure check, spark plugs removed, and while under pressure look for coolant coming out of any spark plug hole.

.
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