'81 Cooling Capacity Question
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'81 Cooling Help Needed
Radiator out of car, new water pump being installed, thermostat and hoses off, yada, yada, yada...
I flushed the car's engine block so that it is now filled with pure water (holding whatever amount it holds with the water pump off and the car's nose slightly elevated). I know that the car's entire cooling system is 22 quarts (5.5 gallons). In order to get a perfect 50/50 mix of coolant and water, I need to know the capacity of the block itself.
Who knows the answer to this?
LO PHAT
I flushed the car's engine block so that it is now filled with pure water (holding whatever amount it holds with the water pump off and the car's nose slightly elevated). I know that the car's entire cooling system is 22 quarts (5.5 gallons). In order to get a perfect 50/50 mix of coolant and water, I need to know the capacity of the block itself.
Who knows the answer to this?
LO PHAT
Last edited by LO PHAT; Oct 22, 2008 at 08:10 PM. Reason: change of title as problems persist
Le Mans Master
Joined: Dec 2007
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From: McHenry Illinois
It might be better to just remove the block drain plugs and drain it. That will let any sediment out as well as getting all the water out. There is a 1/4" pipe plug on each side about an inch above the oil pan to block joint, it takes a 9/16" wrench.
Melting Slicks
Joined: Mar 2006
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From: Orange Park Fl
Dude, you live in Mesa Arizona where it never freezes. You don't want anti-freeze at all. Flush everything good, put in two bottles of Redline Water Wetter and top off with pure water.
Anti-freeze inhibits rust and keeps the coolant from freezing which could produce catastrophic results (cracked block with a hard freeze). Pure water cools better, but does not inhibit rust. Water Wetter will increase cooling efficiency and inhibit rust.
I live in north Florida where there may be a mild freeze once in a while. I have a back flush kit installed and at Thanksgiving I flush and put in one gallon of standard green anti-freeze and two bottles of Water Wetter. This gives me PLENTY of protection in this climate. At Easter, I flush again and just use Water Wetter. I can cruise on the interstate at 90+ mph in 90+ degree weather with the AC on and the temp stays below 200. My cooling system is very clean and rust free.
By the way, NEVER use Dexron anti-freeze! (the late model extended life stuff)
God bless, Sensei
Anti-freeze inhibits rust and keeps the coolant from freezing which could produce catastrophic results (cracked block with a hard freeze). Pure water cools better, but does not inhibit rust. Water Wetter will increase cooling efficiency and inhibit rust.
I live in north Florida where there may be a mild freeze once in a while. I have a back flush kit installed and at Thanksgiving I flush and put in one gallon of standard green anti-freeze and two bottles of Water Wetter. This gives me PLENTY of protection in this climate. At Easter, I flush again and just use Water Wetter. I can cruise on the interstate at 90+ mph in 90+ degree weather with the AC on and the temp stays below 200. My cooling system is very clean and rust free.
By the way, NEVER use Dexron anti-freeze! (the late model extended life stuff)
God bless, Sensei
Last edited by a1sensei; Oct 19, 2008 at 07:55 PM.
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From: Crossville TN
Sorry to differ....but a mix of water and antifreeze is a better conductor of heat than just water. It also raises the boiling point of the coolant mix. As mentioned, antifreeze also has rust inhibitors, etc. that help over the long haul. You may not want to go 50/50, but put a gallon of antifreeze in it, at least.
Melting Slicks
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From: Lubbock Texas
DC
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Yep. After my original post this was the plan I came up with as well. I just wasn't 100% sure that I would be able to get 2.25 gallons of pure coolant into the radiator. In the end it all seemed to go well as I got about 3 gallons of fluids into the radiator and overflow tank.
Now ... I made the decision to go with a 180 degree thermostat. We took the car out a few times tonight, and it keeps heating up to 230 + degrees.
Any ideas for me?
LO PHAT
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From: Florida
You really need to go thru the whole test preceedure until you discover the problem. Otherwise just wild guessing.
Check accuracy of gauge first.
Then all your hoses and cap and even tstat (new have been bad too)
Then check in and out temps or radiator etc......
Check accuracy of gauge first.
Then all your hoses and cap and even tstat (new have been bad too)
Then check in and out temps or radiator etc......
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From: Crossville TN
You may have some trapped air in the system. With a cold engine, take off the radiator cap and start the car. Let it warm up until the thermostat opens...you'll be able to see flow in the radiator and feel heat in the upper hose. If you have trapped air, it should relieve itself with the cap off and at operating temp. Put the cap back on and see if the temp stabilizes OK.
Melting Slicks
Joined: Mar 2006
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From: Orange Park Fl
You won't have to search far to find information on Dexcool turning into mud in the cooling system. Even in the anerobic systems that it was designed for, it does it. GM has had a lot of warranty problems (the late '97's Suburban my wife had several years ago did this). Our older systems make mud of the stuff almost instantly. The only advantage extended life coolant has is the extended like (100k miles). If you service the car regularly (which us older Corvette owners tend to do), the green stuff works great with no problems.
God bless, Sensei
P.S. (7T1vette) Pure water will make the system run cooler than with anti-freeze, something to do with specific gravity I think. But pure water will boil around 215 degrees, which would be bad if you got to that temperature. Anti-freeze does lower the boiling point. But I stand by my original recommendation that if you will never see freezing temperatures, you are better off with Water Wetter and NO anti-freeze!
God bless, Sensei
P.S. (7T1vette) Pure water will make the system run cooler than with anti-freeze, something to do with specific gravity I think. But pure water will boil around 215 degrees, which would be bad if you got to that temperature. Anti-freeze does lower the boiling point. But I stand by my original recommendation that if you will never see freezing temperatures, you are better off with Water Wetter and NO anti-freeze!
Last edited by a1sensei; Oct 20, 2008 at 09:23 AM.
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Anti freeze RAISES the boiling point- which is a good thing to have especially in a hot climate. That's why most people call it 'coolant' and not just 'antifreeze'
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UPDATE:
I've tested the car on a few long drives over the past two days, and here's what I have found.
- the cooling system temperature quickly reaches the desired 180 degrees as it should
- although it takes many additional miles of driving, the temperature will continue to slowly climb past the 180 degrees to about 240 degrees where it will remain (give or take a few degrees in either direction)
- the type of driving doesn't seem to matter (freeway, surface streets, etc)
- I would guess the cooling system temperature gage to be correct based on the fact that the oil temperature gage will also eventually hit and hold 240 degrees (it takes much longer for the oil to reach this temperature)
Where should I start?
LO PHAT
I've tested the car on a few long drives over the past two days, and here's what I have found.
- the cooling system temperature quickly reaches the desired 180 degrees as it should
- although it takes many additional miles of driving, the temperature will continue to slowly climb past the 180 degrees to about 240 degrees where it will remain (give or take a few degrees in either direction)
- the type of driving doesn't seem to matter (freeway, surface streets, etc)
- I would guess the cooling system temperature gage to be correct based on the fact that the oil temperature gage will also eventually hit and hold 240 degrees (it takes much longer for the oil to reach this temperature)
Where should I start?
LO PHAT
Melting Slicks
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From: Orange Park Fl
Melting Slicks
Joined: Mar 2006
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From: Orange Park Fl
LO PHAT, your system is difinately out of whack. I know you have a new pump and T-stat, but those could still be possible culprits.
Also, what condition is the radiator itself in? Check the front to be sure the fins are in good shape (not all bent over), and that it is not full of bugs, leaves and trash (our cars do pick up a lot off the road). Internally is another matter. The inside of the radiator may be clogged, especially if someone ever put Dexcool in it. EPA regs have put an end to radiator shops abilities to do any kind of effective flush. The stock radiator works great when it is in good shape, but if not, now might be a good time to take advantage of the Dewit's sale.
Lastly, this wouldn't be the whole problem, but is your aux electric fan working?
God bless, Sensei
Also, what condition is the radiator itself in? Check the front to be sure the fins are in good shape (not all bent over), and that it is not full of bugs, leaves and trash (our cars do pick up a lot off the road). Internally is another matter. The inside of the radiator may be clogged, especially if someone ever put Dexcool in it. EPA regs have put an end to radiator shops abilities to do any kind of effective flush. The stock radiator works great when it is in good shape, but if not, now might be a good time to take advantage of the Dewit's sale.
Lastly, this wouldn't be the whole problem, but is your aux electric fan working?
God bless, Sensei
Race Director
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This is another technical misconception that won't go away.
Le Mans Master
Joined: Dec 2007
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From: McHenry Illinois
When you looked into the radiator cap, can you see white looking corrosion around the ends of the core tubes ? It seems like you have a coolant flow problem and clogged cores could be the cause. This will gradually raise the coolant temp as you drive. You can check it by draining some coolant out till you can see the cores inside while it's running and see how many are actually flowing coolant, I would bet, not many.
Dean
Dean
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From: Redondo Beach, California
And at the other end of the water and antifreeze debate there's me...I use only pure ethylene glycol - no water- in my 68 and my daily driver. It doesn't freeze here in SoCal either. The 68 has a ZZ4 and runs cool. With pure ethylene glycol there's no corrosion or rust and since the ethylene glycol doesn't boil at normal engine temperatuers, the cooling system remains unpressurized. On the first several times I took it out for a drive, I didn't have a hose clamp on the thermostat housing hose! (The 68 hasn't had water in it since the mid 1970's.) Also, for a high performance engine the elevated boiling temperature of glycol prevents steam pockets from forming in the heads.
Above posts mentioned glycol being banned at race tracks...it is slippery and hard to remove as stated, but another reason it's highly poisonous. I think that because of the poison problem, people in Switzerland have to use propylene glycol as antifreeze since it's not poisonous.
Above posts mentioned glycol being banned at race tracks...it is slippery and hard to remove as stated, but another reason it's highly poisonous. I think that because of the poison problem, people in Switzerland have to use propylene glycol as antifreeze since it's not poisonous.
Team Owner
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From: Crossville TN
I think if you check the "boiling point" charts, a 50/50 mix of antifreeze and water is the highest boiling point you can get. Mixes of [both] higher and lower percentages have lower boiling points. That's the only reason that a 50/50 mix is recommended.
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LO PHAT, your system is difinately out of whack. I know you have a new pump and T-stat, but those could still be possible culprits.
Also, what condition is the radiator itself in? Check the front to be sure the fins are in good shape (not all bent over), and that it is not full of bugs, leaves and trash (our cars do pick up a lot off the road). Internally is another matter. The inside of the radiator may be clogged, especially if someone ever put Dexcool in it. EPA regs have put an end to radiator shops abilities to do any kind of effective flush. The stock radiator works great when it is in good shape, but if not, now might be a good time to take advantage of the Dewit's sale.
Lastly, this wouldn't be the whole problem, but is your aux electric fan working?
God bless, Sensei
Also, what condition is the radiator itself in? Check the front to be sure the fins are in good shape (not all bent over), and that it is not full of bugs, leaves and trash (our cars do pick up a lot off the road). Internally is another matter. The inside of the radiator may be clogged, especially if someone ever put Dexcool in it. EPA regs have put an end to radiator shops abilities to do any kind of effective flush. The stock radiator works great when it is in good shape, but if not, now might be a good time to take advantage of the Dewit's sale.
Lastly, this wouldn't be the whole problem, but is your aux electric fan working?
God bless, Sensei
To answer your questions:
- The radiator (from the outside) is in acceptable condition. I removed it from the car and flushed all of the debris from the fins. There are still some bugs and small stones lodged in it, but it is 60% better than it was previously. Only a few of the fins are bent in two areas.
- The radiator (from the inside) is an unknown. I ran water through it in a reverse direction when it was out of the car and didn't get much of anything out of it. When it is on the car I can see flow while the radiator cap is off.
- The auxilary fan is working. In fact, it seems to be wired to run all of the time (or the sensor for it is perhaps broken).
LO PHAT