1970-W30

captjim, Did you not read my first sentence? I asked a question. Thanks for the answer. The rest of my post was just my opinion just like that article, they are opinions, some believable some not so much. The key words are "insufficient head pressure". There is a lot of leeway there, but I'm not saying they are wrong.......
As far as your complaint, "No matter what I do, I end up "arguing". Try a softer approach, it can't hurt.....

captjim

Fair enough, I can certainly be a PITA. Guilty as charged!! LOL But you stated,
"Lower head pressure does not induce cavitation on a pump"
That is not a question, it is not an opinion, it is a statement that was incorrect. So, I responded. Whenever I make a statement based on experience or my personal opinion, I qualify it with "In my experience" (as I did in this thread regarding radiators) or IMHO, etc In a lot of cases there is no right or wrong, just opinions. In this case, not so much, the science is what it is. I am wrong as often as the next guy and have learned a lot from those with more experience and education. That is the BEST part of these forums, IMHO

tinner

I picked up the Super stat yesterday. I "fixed" the shroud today. I may be ordering my fan next here, but will probably see if this helps with fixing the shroud. The engine is relatively fresh, it as a guess has 300-500 miles on it. The information I get on the mileage is kind of sketchy,It's a long story.....but I know for a fact the miles are low.

1970-W30

Fair enough, let's shake on it and move on. Besides we kinda hijacked the thread anyway........

oldcutlass

Let us know how it works out.

Geez some of these threads take on a whole different dimension.

MDchanic

Just to chime in on the hijack:

Jim's FlowKooler link actually has a very nice and clear discussion of all the things we have been talking about here, and I would encourage all to read it.

It brings up points that both of us have made.

- Eric

jread199

two 1/4" holes drilled in the thermostat helps, I raced dirt track several years ago and learned that some motors run hotter than others, but the ones that run hotter are real aggravating, just my two cents, good luck.

My442

Basics first:

1. Timing - Mechanical and static timing must be correct

2. Carb - A lean condition will cause extra heat

3. Radiator - Must be clean and leak free

4. Shrouds - All of the factory shrouds should be in place

5. Exhaust gas - Be sure to test to see if there is exhaust gas in the coolant.

My 442 has an aluminum radiator, hi flow thermostat (180), clutch fan, and all factory shrouds in place. It never runs over 180-185, even on a 95 degree day.

s i 442

Bottom line is 180 is the magic number everyone wants.
Do whatever it takes to hit that number or you will never be happy!
It will cause you many sleepless nights and non productive days at work.

brown7373

When I first bought my 72 I read somewhere (service manual, owners manual ?) that the operating temperature was 200 degrees. That made sense because the correct factory t-stat is 195. I'm not sure what your 1969 (?) is, but I'd bet it's the same. Tinner, if it was my car, I'd make sure all the basics were corrected first. No leaks of coolant, a good pump, a good factory fan (I agree it is hard to beat the clutch fan), all the correct seals around the radiator and shroud in place so the air go through the radiator and not around it and a good radiator. Also, are you running a 50/50 mix of anti freeze? There was an interesting article on engine cooling in the August issue of Hemmings Classic Car. One of it's points was straight water sometimes registers lower temperature on the gauge, but the actual temperature of the engine is higher than with a 50/50 mix. A 50/50 mix of anti freeze cools much better than straight water.

You also are running a 3.73 gear which means more rpms and higher engine temps, unless you have an overdrive transmission. 200 is definitely not too hot to continue driving. But 3 mile trips are not long enough to really determine where the engine temp will settle. As far as the t-stat goes, it only controls at what temp it opens, not what temp the car runs at. Your car won't run at 160 with a 160 t-stat unless you have a cooling system capable of cooling sufficiently to keep it at that temp. Hence, fix the basics first.

MDchanic

True in the sense of "makes the entire cooling system work better," but false in the sense of "transfers heat out of the system more efficiently."

See this thread for more information.

- Eric

brown7373

I am no scientist, only a hobbyist. The article I referred to, written by Ray Bohacz states that water does absorb heat better (specific heat rating of 1) but because of high surface tension, it doesn't do as effective a job of removing the heat from the head. Eric, I am not sure what that means, but I understood it to mean the pure water tends to stick to the head (relatively speaking) whereas the coolant mix flows away better and is replaced by incoming coolant mix better, thus cooling the engine better.

MDchanic

I would agree with all of that.

Pure water carries heat very well, but is not the best coolant, which is why we generally advise people to use 50/50 antifreeze / water here.

- Eric

oldcutlass

The quote catch all for antifreeze is 50/50 mix, however that is not correct in some areas that are normally warmer or extremely colder.

This is the percentage vs lower temp:


Notice the highest efficiency is between 60 and 70 percent. There are places in this country where you can get away with 30-40 percent where others can require 60-70 percent.


This is the percentage vs temp upper limits, this chart is really interesting on the effects as a coolant:

MDchanic

The lowest freezing point is between 60 and 70 percent - it has nothing to do with efficiency.

Nice clear charts, though. Thanks.

- Eric

oldcutlass

I believe efficiency would be the correct term as any higher percentage in the mix actually has a reverse effect for the freezing temp rating.

MDchanic

According to the New Oxford American Dictionary:
Efficiency measures the amount of energy put in compared to what you get out.
A more efficient engine goes farther, or faster, on a given amount of fuel.
A more efficient air conditioner makes more cold air for a given amount of electricity.
A more efficient information gathering process gets more information on more people with less work done by the government.

Your meaning is just not the meaning of the word.

- Eric

oldcutlass

Efficiency


Efficiency is the capability of acting or producing effectively with a minimum of waste, expense, or unnecessary effort. The term has widely variant meanings in different disciplines. See

• Algorithmic efficiency for its use in computer science.
  • efficiency is also a computer science term used when discussing parallel computing and speedup.
• Economic efficiency for its use in economics.
• Textual efficiency for its use in linguistics.
• Efficiency (statistics) for its use in statistics.
• Electrical efficiency for its use in electronics and electrical engineering.
• Fuel efficiency for its use in automobiles (also known as "gas milage").
• Mechanical efficiency for its use in engineering.
• In rocket propulsion, specific impulse is a measure for mass-efficiency, though a very high specific impulse is not energy-efficient
• Thermodynamic or "engine" efficiency for its use in Thermodynamics, Statistical Physics, related fields, and engines and motors.
• Volumetric efficiency for its use in engine design

In several of these cases efficiency can be expressed as a result as percentage of what ideally could be expected, hence with 100% as ideal case. This does not always apply, not even in all cases where efficiency can be assigned a numerical value, e.g. not for specific impulse.

MDchanic

Grrrrrrrr.

Yes, and NONE of those uses is related to concentrations of solutes and their relation to boiling point elevation and freezing point depression.

I'm not getting anywhere, because I can't prove a negative, so I will just give up, but if there is anyone on these boards who is a chemical engineer or chemist and can point to the word "efficiency" ever being used in this context (as opposed to the context of catalysts), please, by all means, back me up here. Thank you.

- Eric

captjim

Hey oldcutlass, if copper and I were having the exact same exchange, you would be jumping in with some kind of condescending remark. Basically, for 90% of us, a 50/50 mix works fine. Here in FL where it rarely freezes, we can go less, but most guys I know buy the pre-mix 50/50 anyway. Even if it never freezes, you want coolant to reduce corrosion and lubricate the water pump.

oldcutlass

Hey Eric, it's statistical efficiency based on 100% for desired effect in temp drop(output), vs a varying input percentage mix of substance. Efficiency can be applied to many things besides what you were referring to earlier. Cause and effect.

Jim the difference between my conversation with Eric and yours and Coppers is that we aren't berating each other. We are having am intelligent exchange of semantics.

The thing I was getting at is it works both a coolant by raising the boiling point of water that is proportionate to the percentage mixed in water up to 100% ethyl glycol. However to inhibit freezing the scenario reverses at around 65%. Most only think it keeps the fluid from freezing.

Here in Mayberry I can get away with around 30/70 of coolant/water with a bottle of water wetter.

MDchanic

I see your point, but I would submit that freezing point depression / boiling point elevation is a universal natural phenomenon observed in all solute/solvent complexes, and thus not subject to the concept of efficiency, any more than how efficiently a rock falls from a height.

Anyway, I think we're arguing in different directions right now, not to mention the thread-jack, so I'd just better stop.

- Eric

1970-W30

To me, I read it as 70/30 as being the most efficient in preventing freeze up, but not necessarily the most efficient ratio for heat transfer, two completely different objectives......

brown7373

But what effect does pressure in the system have. I know the boiling point increases when the pressure increases. How does increased pressure effect the freezing point?

oldcutlass

Pressure is not considered in the freezing point as the engine provides suitable heat and the antifreeze will bring the freezing point down chemically. Engines don't freeze when they are running it's the radiator that has the issue. That's why you see big trucks with the radiator covered partially in winter.

captjim

Like oldscutlass stated, no effect on freezing. Each pound of pressure raises the boiling point roughly 3 degrees. That is why an engine running with water at 220 degrees in a 15 lb system won't boil over.

tinner

I haven't had a chance to get the car out yet, I've been too busy. I just painted my "new" factory clutch fan today. I have fixed my shroud until I find a suitable replacement. I think I am taking it to a local car show on Sunday....unless I have problems on the way. I live in Wisconsin, I always have mixed antifreeze.

ziff396

Mine is the same however I am only running the main shroud and nothing else. 180 thermostat and runs 180 all day in to the 90's. Works for me without all the technical responses. Why? It works, so I don't question it.

s i 442

I hate anti freeze, I use 1 gallon in the winter and as soon as spring hits out it comes and in goes water and a small bottle of water pump lubricant.

tinner

I am still having issues with it overheating. I fixed my fan shroud and I installed a factory style fan & clutch. I will try a HD clutch and if that doesn't work... another radiator that I have for another project. I am running out of ideas.

M-14

When is it overheating? At idle/low speeds or going down the road?
If its overheating going down the road then its not fan/shroud related.

oldcutlass

What are your temps @ idle, stop and go, and cruise now? What thermostat are you currently running? Can you post a picture of your fan position in the shroud now?

tinner

It runs hot while driving. It will sit at 200 at idle, driving it will hit 210 and climb. I had to stop three times before I could get it home today....not enjoyable. I drove the car about ten miles at 208 then it started to climb. It was 70 degrees. It didn't matter what speed/rpm I was driving, it was getting hot. I put in a Stant 195 superstat and used aluminum to patch the missing pieces in the shroud. The fan I put in was used with a used clutch. The fan is sitting just inside the shroud. There may be up to 1/2" sitting outside the shroud toward the botom of the shroud at most. I was at a car show today and looked at other Cutlass's and the fan position appeared to be the same. I will get pics tomorrow.

oldcutlass

The 195 thermostat is probably to high, you need to get a 180 Superstat. I would not go any lower in Wi. A 195 degree thermostat starts to open at 195, so 200 - 208 at idle is normal. My concern is why it's climbing at cruise.

captjim

Because cheap-azz aftermaket radiators don't cool well, read post #13 in this thread. I can't tell you how many times I have seen this happen.

M-14

Water pump impeller erosion could do that.
I just looked at your engine picture, your not running a heater line off the back of the intake, I don't know how important that is to have a loop between that & the water pump, is the by pass enough?

oldcutlass

IMHO that doesn't look like a cheap-azz radiator, and generally they work fine at cruise, just not at idle.

captjim

He sais it was a 3 core E-bay rad. I had a 3 core from Advanced on my mild 355, overheated at cruise constantly. Did all the normal stuff, then changed to an aluminum F-body rad. After that I rarely even needed the fan. My understanding is they look good but have a lot less fins per sq/in

oldcutlass

I have a cheap azz 1" thick aluminum radiator with plastic tanks on my car and it will run all day long @ 195-200 cruising with an ambient temp of 100+. In traffic it will climb to 220 but recover quickly once it gains speed.

With the OP's ambient temp around 70 it should be staying pretty close to 200 cruising.

tinner

The water pump is in good physical condition as far as I can tell. I had it off a little while back and it looked fine. I will try a 180 stat, but I am not sure that is the main problem. Has anyone ever see an impeller slip? I was talking to my Dad about it yesterday. He was also questioning about a crack at the exhaust port and told me to check for bubbles in the radiator. Has anyone seen this on an Olds? I will do the stat & probably swap radiators for grins as I have another different cheap azz plastic tank one too. It was my first long run in this car since '97 and it wasn't that fun watching my gauge climb. The other problem is that I am so busy right now and it's going to get busier.