Just Trying to Keep Myself in Denial
05-13-03, 02:38 PM
#27
development
Thread Starter
Spurvo - nice write up. I especially liked the wiggling molecules, really painted the picture 
I really hate that your car is silver and had bad seals with minimal signs and my car is silver with minimal signs...however, I definitely did NOT have frothy champagne with my upside down Sprite bottle (did you leave the ring around the top? mine test didn't seem to seal as nicely as yours.
Let's see if I have this striaght...run a tube into from the top of the AST to a bucket (perhaps) with coolant in it and see if the AST wants to dump coolant into (simulated overflow) it before my linearized temp gauge hits the hot normal line (220F).
Thing is, I've checked (even after a hard/hot run) and coolant doesn't pee out until I'm not around and it's been heat soaking for awhile. I've only caught it peeing a couple of times...but have seen the wrath numerous times. I think that alone is what is giving me hope.
I need to find out why coolant doesn't want to go back to the sys. Say I start with the OF on F...drive awhile...next day OF will be 3-4 bars above F, open filler like an idiot and the coolant is low. hmmm, I'll fix that and fill that mo'fo up. Why is my car peeing coolant??? Because I keep filling it up once the OF is too full. Why is the OF too full, that I don't know...will putting an FC filler neck on and eliminating the AST help this? I have no idea.
Thanks to who ever reads this...all over the place
-Dub
I really hate that your car is silver and had bad seals with minimal signs and my car is silver with minimal signs...however, I definitely did NOT have frothy champagne with my upside down Sprite bottle (did you leave the ring around the top? mine test didn't seem to seal as nicely as yours.
Let's see if I have this striaght...run a tube into from the top of the AST to a bucket (perhaps) with coolant in it and see if the AST wants to dump coolant into (simulated overflow) it before my linearized temp gauge hits the hot normal line (220F).
Thing is, I've checked (even after a hard/hot run) and coolant doesn't pee out until I'm not around and it's been heat soaking for awhile. I've only caught it peeing a couple of times...but have seen the wrath numerous times. I think that alone is what is giving me hope.
I need to find out why coolant doesn't want to go back to the sys. Say I start with the OF on F...drive awhile...next day OF will be 3-4 bars above F, open filler like an idiot and the coolant is low. hmmm, I'll fix that and fill that mo'fo up. Why is my car peeing coolant??? Because I keep filling it up once the OF is too full. Why is the OF too full, that I don't know...will putting an FC filler neck on and eliminating the AST help this? I have no idea.
Thanks to who ever reads this...all over the place
-Dub
05-13-03, 03:08 PM
#28
don't race, don't need to
LOVE to read myself write...
Pressure test the system. You will find the leak that way. Do it hot, do it again cold. Have faith, brutha.
For the overflow test, yes run a tube into a bottle (I used Cranberry juice bottle. I LOVE the different liquids going in, so does the silverfish!) and run the engine. I have my linearized gauge set so the needle points between the two cold marks when I'm running on the freeway (about 177 to 180F) and I was having coolant come out before the needle even moved. If yours does not push coolant out the AST until the needle is say halfway (~210 or so), then your O=rings are very likely fine, and you need to go after the hoses, caps, or AST to OF line. What hose clamps are you using, may I ask?
Pressure test the system. You will find the leak that way. Do it hot, do it again cold. Have faith, brutha.
For the overflow test, yes run a tube into a bottle (I used Cranberry juice bottle. I LOVE the different liquids going in, so does the silverfish!) and run the engine. I have my linearized gauge set so the needle points between the two cold marks when I'm running on the freeway (about 177 to 180F) and I was having coolant come out before the needle even moved. If yours does not push coolant out the AST until the needle is say halfway (~210 or so), then your O=rings are very likely fine, and you need to go after the hoses, caps, or AST to OF line. What hose clamps are you using, may I ask?
05-13-03, 03:49 PM
#29
development
Thread Starter
Originally posted by spurvo
What hose clamps are you using, may I ask?
What hose clamps are you using, may I ask?
Thanks for the help.
I need a "Bat" signal for you, although when I asked for you to chime in...you came thru!
Thanks bud
05-13-03, 04:01 PM
#30
don't race, don't need to
Shurely, Shirly!
Oops! Hee..
I will mention that I'm trying new hose clamps from McMaster Carr, a la RonKMiller. They are NOT worm screw type as I tried those two before the rebuild, and was NOT happy. They seem to relax over time, and really chew up the hoses. Instead, I'm trying T-bolt style clamps. For the smaller hoses, I'm also using a bolt style clamp. I'll post the numbers if anyone is interested, and my impressions after some miles. First impression is very good, as the hoses do NOT move once clamped, and these don't chew into the hoses. Only the lower rad hose leaked at the water pump housing, and after thightening harder, that stopped!
Glad I can help SOME one around here, after aLL the help I've gotten from this forum. What a life saver!!!
Oops! Hee..
I will mention that I'm trying new hose clamps from McMaster Carr, a la RonKMiller. They are NOT worm screw type as I tried those two before the rebuild, and was NOT happy. They seem to relax over time, and really chew up the hoses. Instead, I'm trying T-bolt style clamps. For the smaller hoses, I'm also using a bolt style clamp. I'll post the numbers if anyone is interested, and my impressions after some miles. First impression is very good, as the hoses do NOT move once clamped, and these don't chew into the hoses. Only the lower rad hose leaked at the water pump housing, and after thightening harder, that stopped!
Glad I can help SOME one around here, after aLL the help I've gotten from this forum. What a life saver!!!
05-13-03, 08:34 PM
#31
Eats, Sleeps, Dreams Rotary
Originally posted by spurvo
Now, once the car starts to cool off, typically 30 to 45 minutes after shutoff, the coolant begins to physically contract. The molecules wiggle less, and take up less space. As this occurs, the shrinking volume of coolant in the engine creates a vacuum in the coolant system. This vacuum literally sucks coolant back into the engine from.. you guessed it... the overflow. In fact, the amount that expanded into the tank is the amount that goes back in, if all is working well.
Now, once the car starts to cool off, typically 30 to 45 minutes after shutoff, the coolant begins to physically contract. The molecules wiggle less, and take up less space. As this occurs, the shrinking volume of coolant in the engine creates a vacuum in the coolant system. This vacuum literally sucks coolant back into the engine from.. you guessed it... the overflow. In fact, the amount that expanded into the tank is the amount that goes back in, if all is working well.
Leme try and explain mysled a bit better...that cap has a spring which gets compressed when there is pressure in the system, thus pushing to the OF bottle.
Now, a vacuum happens when it cools...now the vac is pulling against the AST cap and working along with the spring...Doesn't that cap work kinda like a one-way valve? Kinda like a check valve? you can blow through it but can't suck on it (hehe I said suck on it
)
05-14-03, 12:57 AM
#32
Speed Mach Go Go Go
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I chenged my AST cap to 0psi and put back my Blitz 18.5psi cap on the filler neck. Since the hole to the AST on the filler neck is lower then the cap plunger/spring dealy then I don't want coolant to exit there under pressure. Air easily exits the OEM AST into the overflow now and my AST sounds like a coffe pot perculating perfusely.
05-14-03, 07:50 AM
#33
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I can't say that I've actually looked at a radiator cap very closely, but according to www.howstuffworks.com, there is another spring-loaded valve to draw coolant back in under vacuum.
Originally posted by apneablue
Ok, I understand that the coolant expands and contracts with the temp changes...What I don't understand is if it creates a vacuum on the AST neck, how does it pull in coolant through the sealed cap...
Leme try and explain mysled a bit better...that cap has a spring which gets compressed when there is pressure in the system, thus pushing to the OF bottle.
Now, a vacuum happens when it cools...now the vac is pulling against the AST cap and working along with the spring...Doesn't that cap work kinda like a one-way valve? Kinda like a check valve? you can blow through it but can't suck on it (hehe I said suck on it )
Ok, I understand that the coolant expands and contracts with the temp changes...What I don't understand is if it creates a vacuum on the AST neck, how does it pull in coolant through the sealed cap...
Leme try and explain mysled a bit better...that cap has a spring which gets compressed when there is pressure in the system, thus pushing to the OF bottle.
Now, a vacuum happens when it cools...now the vac is pulling against the AST cap and working along with the spring...Doesn't that cap work kinda like a one-way valve? Kinda like a check valve? you can blow through it but can't suck on it (hehe I said suck on it
)
05-14-03, 12:33 PM
#34
don't race, don't need to
Yes, the "pressure" cap is actually a two way system. It requires whatever pressure the cap is rated for to allow coolant past FROM the engine TO whatever overflow you are using. But it requires very little vacuum to allow coolant to pass FROM the overflow TO the engine. Physically, it's the little brass plunger in the middle of the cap that allows the coolant past.
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