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OK I have a question about radiator pressure/flow.

 

Heres how I came to have such a question.

 

For reasons I won't get into here/now I had the rad cap off the RX and the v-belt was removed. I started the car and let it run just a few revs (very few, I'm a dumdum but not an idiot). Much to my surprise water shot up out of the radiator. Now I says to myself I says "Maybel, the water pump aint turnin' so what in tarnation is pushing that water around?"

 

Can anyone explain this to a small town simpleton?

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OK I have a question about radiator pressure/flow.

 

Heres how I came to have such a question.

 

For reasons I won't get into here/now I had the rad cap off the RX and the v-belt was removed. I started the car and let it run just a few revs (very few, I'm a dumdum but not an idiot). Much to my surprise water shot up out of the radiator. Now I says to myself I says "Maybel, the water pump aint turnin' so what in tarnation is pushing that water around?"

 

Can anyone explain this to a small town simpleton?

 

sounds like a familiar blown headgasket story, but i could be wrong (i hope for your sake)

although, the turbo on your RX might be pushing some water out (of it's cooling setup), i'm not sure how the coolant runs thru the turbo, but it would make sense if it's cycling water out as the exhaust spins it, it's gotta go somewhere . . .

?

combine this with your cooling issues getting to that meet the other weekend . . . and things don't look pretty :dead: (head gasket)

chris

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(head gasket)

chris

 

Shh shhhhh for gods sake be quiet! I hear these things hardly ever blow head gaskets :popcorn:

 

 

Yea it has gotten warm 2 times now but not overheated (I hope??) The guage just went higher than It does during normal driving.

 

I am hoping for the turbo story

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sorry says quietly "don't hold your breath" [/audio_file]

 

 

Shh shhhhh for gods sake be quiet! I hear these things hardly ever blow head gaskets :popcorn:

 

 

Yea it has gotten warm 2 times now but not overheated (I hope??) The guage just went higher than It does during normal driving.

 

I am hoping for the turbo story

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That's a compression leak into your cooling system. Bad head gasket(s) or cracked head(s).

 

Coolant only "shoots" out of the radiator cap when it's put under pressure. Otherwise it sits there and does nothing at all (especially without the water pump turning). Convection will slowely circulate it to some extent, by a gyser out the cap with the engine cold is a sure sign of the cooling system being pressurized by compression gasses.

 

Since you also mention some overheating, you should STOP driving it immediately. You risk blowing radiator or heater core hoses, blowing the tanks off the radiator, or blowing out the heater core (not fun to replace). The cooling system was only designed to handle 13 psi, and the stuff is probably only pressure tested durring manufacturing to 25 psi or so. The cylinder compression gasses from just one cylinder can be upwards of 200 psi or more. I just replaced the heater core in my 91 SS for this same reason. The last owner (that drove it) didn't stop driving and all the tubes in the core split right at the junction to the bottom tank. Not pretty, and not cheap or simple to fix - removal of the entire dash is required.

 

How high was the gyser? I've seen upwards of 4 or 5 feet of coolant spray from an engine with multiple, completely blown-out cylinders.

 

Anyway - sorry for the bad news.

 

And just so you know, turbo's do not circulate coolant at all. They have a flow through system and rely on the water pump to circulate coolant through them.

 

GD

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And just so you know, turbo's do not circulate coolant at all. They have a flow through system and rely on the water pump to circulate coolant through them.

 

GD

 

ah, thank you for the clarification GD.

 

:headbang:

chris

 

Major, if ya want some help, i'm just up the street. :drunk:

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That's a compression leak into your cooling system. Bad head gasket(s) or cracked head(s).

 

 

How high was the gyser? I've seen upwards of 4 or 5 feet of coolant spray from an engine with multiple, completely blown-out cylinders.

 

Anyway - sorry for the bad news.

 

And just so you know, turbo's do not circulate coolant at all. They have a flow through system and rely on the water pump to circulate coolant through them.

 

GD

 

sigh oh well, it was really just a matter of time. The geyser was not hight at all, just enough to push it out of the rad, maybe 2"-3"

 

 

THx GD.

 

hey chris, sold that motor yet??

and yes I could use a hand but ive never done the head gasket (hope its not cracked), how long you think it will take? I have to go see my Bro grad from college this weekend tho

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hey chris, sold that motor yet??

and yes I could use a hand but ive never done the head gasket (hope its not cracked), how long you think it will take? I have to go see my Bro grad from college this weekend tho

 

time depends on if the engine is in the car or out, but we should be able to knock it out in a day either way. if you had any dead lifters, might be a good time to find replacements, and of course timing belts/tensioners if those haven't been replaced recently (they've got to come off anyway). if you really want to do it right, plan for a couple of days without the car so that we can send the heads to be machined/cleaned up.

 

pretty sure my engine is sold, sent off a pm just to verify pick up . . . but if for some reason it doesn't work out . . . there's an easy fix for ya :D

hold off on ordering the parts (intake manifold gasket, headgaskets, valve cover gaskets, timing belt cover gaskets, etc.) until i'm more sure on my engine's status if you like . . .

be glad to give you a hand regardless!

 

chris

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So if the v-belt is on, and the water pump is working correctly, should the radiator never "puke" coolant, ever? Even as the engine temp rises to running temp?

 

no. if you are doing an initial fill of the cooling system (like after flushing it) and you've topped off the radiator, you can expect constant drizzle of fluid out of the radiator as it "burps" the air out of the system, and especially when the engine gets to "operating temp" and the thermostat opens for the first time, then it really surges out for a second. but after that the level in the radiator should immediately fall, allowing you to re-fill that fluid that drizzled out. once you've done this, and waited a bit to make sure all the bubbles are out, put the cap on and, ta-da! you have a pressurized cooling system that will put any extra fluid it has into the overflow container - instead of dribbleing it out of an open radiator cap.

 

chris

 

**edit** you know this Evil, why am i explaining this to you?!

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To be clear this happened with the v-belt removed (absolutely dead water pump). And I may have exaggerated when I said water 'shot out' of the radiator, it more just kind of oozed up and out. The real point was that I expected ABSOLUTELY NO action in the coolant due to no water pump. I think GD has pretty well answered the question but I am open to denial if someone wants to offer an alternative explanation.

 

Da Nile aint just a river in Africa ya know

 

I will begin parts procurement Chris

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Even as the engine temp rises to running temp?

 

Coolant, as all fluids, will expand as it heats. It does so pretty slowly, but yes it will overflow if you let it heat up long enough. It doesn't "shoot" out though - it just runs over the top of the filler neck and down the sides.

 

Irregardless, no substantial heating occurs in the first minute or two of operation so what the coolant does as it reaches operating temp has no bearing on Major Lazy's original question - the problem being experienced here is no doubt a compression leak to the cooling system.

 

GD

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I will begin parts procurement Chris

 

Just make SURE there is no air in the system - air has the capability to heat and expand more rapidly than water/coolant, and air bubbles can easily cause overheating with the EA82's.

 

But most likely you are wise to do the HG's. Get the Fel-Pro's and get the rest of the gaskets from the dealer.

 

GD

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Just make SURE there is no air in the system - air has the capability to heat and expand more rapidly than water/coolant, and air bubbles can easily cause overheating with the EA82's.

 

But most likely you are wise to do the HG's. Get the Fel-Pro's and get the rest of the gaskets from the dealer.

 

GD

 

 

The coolant oozed out of the radiator CLEARLY in response to the throttle application. revvv....oooze, revv....oooze. And the motor was cool with no chance to warm up, i mean it ran for like 10 sec MAX in 3 separate bursts

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The coolant oozed out of the radiator CLEARLY in response to the throttle application. revvv....oooze, revv....oooze. And the motor was cool with no chance to warm up, i mean it ran for like 10 sec MAX in 3 separate bursts

 

i'll go down "De Nile" with you for a sec here . . .

had you just added coolant to the radiator? revving itself can cause oozing, especially if the coolant level was just topped off, but all my experiences with that have been while the water pump was running, so . . . (?)

do you have any other signs of bad H.G.'s? (like, is it a subaru turbo? :D)Milkey gunk buildup on oil cap . . . coolant smell in car when running heater, sometimes even getting condensation on the windshield when you first turn on the defrost setting . . . i'm sure if you drained the oil, you'd know for sure (water pools on top of the oil) . . . lotsa steam lately when you've been driving?

 

:horse:

chris

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i'll go down "De Nile" with you for a sec here . . .

had you just added coolant to the radiator? revving itself can cause oozing, especially if the coolant level was just topped off, but all my experiences with that have been while the water pump was running, so . . . (?)

do you have any other signs of bad H.G.'s? (like, is it a subaru turbo? :D)Milkey gunk buildup on oil cap . . . coolant smell in car when running heater, sometimes even getting condensation on the windshield when you first turn on the defrost setting . . . i'm sure if you drained the oil, you'd know for sure (water pools on top of the oil) . . . lotsa steam lately when you've been driving?

 

chris

 

none of those symptoms, and I have been looking. Weird thing is, now that I have the water pump hooked back up the water does not surge. hmmm God i love false hope

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none of those symptoms, and I have been looking. Weird thing is, now that I have the water pump hooked back up the water does not surge. hmmm God i love false hope

 

i believe in religious circles it's called . . . blind faith :D

give the car an oil change just to be sure . . . .

and go buy lotto ticket :headbang:

chris

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no. if you are doing an initial fill of the cooling system (like after flushing it) and you've topped off the radiator, you can expect constant drizzle of fluid out of the radiator as it "burps" the air out of the system, and especially when the engine gets to "operating temp" and the thermostat opens for the first time, then it really surges out for a second. but after that the level in the radiator should immediately fall, allowing you to re-fill that fluid that drizzled out. once you've done this, and waited a bit to make sure all the bubbles are out, put the cap on and, ta-da! you have a pressurized cooling system that will put any extra fluid it has into the overflow container - instead of dribbleing it out of an open radiator cap.

 

chris

 

**edit** you know this Evil, why am i explaining this to you?!

 

 

Just figured some didn't know....:banana:

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