[tom s]

I have found 30 degrees on mine?Tom

[67drake]

Originally Posted by tom s

I have found 30 degrees on mine?Tom

Yeah, I checked temperature difference, then looked up what it should be. I read that 20 is “normal”, I expected mine to be less, as I do believe radiator is restricted. I’m used to seeing lots of coolant flow in the radiator when engine is running, mine doesn’t have a whole lot of movement. So regardless I want to pull the radiator and take it in to be cleaned.

[Schurkey]

Originally Posted by 67drake

I drained the system yesterday, then flushed till water ran clear.

Did you remove both block drain plugs?

[67drake]

Originally Posted by Schurkey

Did you remove both block drain plugs?

Yes. Didn’t have to remove starter for drivers side plug either. Got in there with a 7/16” on a wobble extension.
Local radiator shop is out of business. So found a place in Dubuque, about an hour away. Pulling radiator tonight to drop off tomorrow. Taking a better look at the radiator, it’s due for a once over at a shop anyway. Frankly, I’m surprised it’s not leaking.
Going to pull block plugs again when I flush that thermocure out of the block. Have a thermostat and distilled water ready to go.
Feel better knowing I’m doing this long overdue maintenance. We’ll see how much it helps running temperatures.

[Don 79 TA]

i love the water wetter stuff
GREAT for system protection, especially when using mostly distilled water
as for cooling, can't really say, maybe it may help, but no magical bottle is going to reduce engine temps 20+ degrees, unless you happened to burp the air while doing it or some other issue

[MatthewKlein]

Originally Posted by 67drake

k. Have a thermostat and distilled water ready to go.

Dexcool extended life antifreese was junk when it came out. The formula has sense been sorted out. Every car manufacturer uses their version and its wonderful. "Global" antifreeze premixed 50/50 should last about forever. It has excellent corrosion protection.

There is a lot of excellent advice in this thread.
Poor tune/ignition timing. Vacuum advance at idle helps to lower temps
Water pump, plate clearance, water pump impeller rusted away, water pump sleeve gasket deterioration
Proper fan clutch engagement
Fan shroud
Radiator function

[67drake]

Well glad I pulled the radiator. I didn’t notice how bad it was with the original shroud on one side and the AC condenser on the other, but core was not in that great of shape. In my experience when I see that green corrosion, it’s at least a pinhole.
The radiator shop called today and said they don’t think repairing it would hold up, and after I told them this is a fairly original car still, we agreed to have them recore it. Leaving for Alaska next week, so it might be awhile before I get back to this as they have to order the core.
Another issue. I noticed my fan clutch was leaking- the spring is full of oil. So I’ll be replacing that too. Question is I read a lot of info here on modifying that spring so that it locks up at a cooler temperature, but don’t really want to do that unless it’s needed. I wasn’t running hot at idle, just highway speeds. So I might just go with an OEM looking replacement or just wait till I get this back together, as it’s no big deal to pull the fan and clutch back out.

[Tim Corcoran]

Rislone Hy-per Cool, my friend uses it in his drag car and swears his engine runs 10 to 15 degrees cooler. No need to run anti-freez/coolant with this stuff

[67drake]

Back from vacation, and went to Dubuque to pick my newly cored radiator up today. I should have some time this week to put it back in and see if it runs cooler. It certainly LOOKS better.

[67drake]

Just an update.
So today I put the radiator back in. I also put the block drains back in and opened the petcock and ran the engine with a hose in the radiator opening. I wanted to make sure I got any leftover block flush out of the heater core and any spots that wouldn’t drain. I had the car idling with the heater on, and reved it every few minutes. I then pulled block drains again and left petcock open to drain it all out.
I had installed a 160 degree thermostat already, so filled system up with distilled water and antifreeze, and took it for a spin.
OK, it’s a LOT better, but could still be cooler. When I started this thread engine temperature would be 185 at 55 mph, and at least 200 at 65. Now it’s about 185 at 65 and 190 at 70-80 mph. Temp will drop right back down to 180-185 when I slow down and cruise through a small town, like 25-35 mph.
So next time I get out in the shop I’m going to recheck my timing advance curve to see if something changed since I had the distributor recurved.

[steve25]

Did you burp the system before you put the cap on for the drive you did?

Anyway I find nothing wrong with the temps your reporting now really!

[grivera]

Those temps seem fine. Did you put thermostat in a pot of hot water to check at what temperature it fully opens?

[67drake]

Yes, and nobody local had a 160 degree, so figured I’d check the old one instead. It opened at almost exactly 160, and was wide open by 180-185.
There was already a hole drilled in it from before, so system filled easily. I filled it up, started the engine and ran it till it warmed up a little and kept topping off as needed. I figured I’d check again today after it cools down.
So if the cooling system is up to snuff, in theory wouldn’t the engine stay in the 160 degree area at all times? Or is that just not realistic?

[i82much]

160 is where it starts to open. your car is fine!

[Gator67]

Originally Posted by 67drake

...Now it’s about 185 at 65 and 190 at 70-80 mph. Temp will drop right back down to 180-185 when I slow down and cruise through a small town, like 25-35 mph. So next time I get out in the shop I’m going to recheck my timing advance curve to see if something changed since I had the distributor recurved.

Checking timing is a good idea. But 190 doesn't seem too hot unless the temperature continues to creep up the longer you drive at 70-80mph.

Originally Posted by 67drake

...So if the cooling system is up to snuff, in theory wouldn’t the engine stay in the 160 degree area at all times? Or is that just not realistic?

I had a 160 degree thermostat in one of my cars. In the winter it would stay around 160. In the summer, it just delayed how long it took until the temperature got to the point where it didn't increase any more (around 185). I replaced it with a 180 degree thermostat because I was concerned the car was running too cool in the winter and wouldn't warm up sufficiently, especially on shorter drives. I found the change makes absolutely no difference to my summertime temps. It just gets to 185 a bit quicker. My situation may not apply to you given winter-summer temps here are typically 40s and 100s respectively,

[67drake]

Thanks guys.
Yeah, I’ll have to get it out there on a real hot day and check it out. By the time I took it out last night, it was only about 78 degrees. I’ll take it for a ride in the hills on a hot day when I have time.
I just have plans to take my cars on trips in the summer, so they need to be ready for trips of quite a few hundred miles without me sweating all the issues.

[67drake]

Towards the end of my 40 mile trip today, speeds of constant 65-70. Only 75 degrees out, but made for a nice drive.
On to timing and replacing these 25 year old tires.

[Don 79 TA]

Originally Posted by 67drake

Towards the end of my 40 mile trip today, speeds of constant 65-70. Only 75 degrees out, but made for a nice drive.
On to timing and replacing these 25 year old tires.

I know off topic, but man........ my experience with purchasing various tires lately.....
i'd say keep the old ones lol
i know, it's a safety issue, but man has QC gone really down on tires, and tire shops will just push you right out, so becareful when get them.

i just got some ET street R's, and one needed .75oz, the other had 5.75 oz and these were new wheels and tires from Jegs, and i can't get any of them on the phone to talk about it. They do work, but man, 5.75oz on new tires/wheels??????
Forget the Michelin ordeal i went through on my Truck a few months ago, my gawd they put a sh!t ton of weights on, and you saw the tires bobble up and down clear as day. but i did get that resolved (without a painful intervention of course).

side note to add to original topic, i will raise the front end up when "burping" the system, helps a lot, but then again, i always try to use stats that have air bleeds, so some of them have arrows on which way it faces (the last few balanced sleeved stats had that on them)
also, as mentioned a lower stat may/may not help as others mentioned it just delays the rise in temps
always keep an eye out for air flow, air deflectors, spoilers, and of course debri in the radiator (and of course your tunes)

I will say as well, i notice a slight difference when i run T4 or Prodrag3 fuel, the ethanol in there does help keeping the temps slightly down especially in 105+ degree temps here and running 3rd gear in the 35mph zone areas, personally i like to mix them with VP110, that 110 fuel pops very quickly

[ChuckDH]

This subject always seems to get the pitchforks out for me. Reasons why I don't post much, but I am feeling a little froggy today.
I do not use antifreeze in any of my cars that do not see freezing temps. A high concentration of ethylene glycol actually hurts the heat transfer and I have solved cooling issues in the past with plain old distilled water. Antifreeze or so called coolant companies have marketed their products so everyone uses them 50/50 whether they need it or not.
Nothing transfers heat in your radiator as good as water. People think that modern antifreeze helps cool your engine, but it doesn't, it only raises the boiling point of the water. It doesn't make the water any cooler, it just makes it boil in your radiator at 268 degrees instead of 257 degrees with a 15lb cap. Antifreeze does provide, freeze protection (my cars do not leave the garage below 50) and Corrosion protection. (I use Prestone's separate rust additive, and it works better than what comes in antifreeze). If you are concerned about freezing temps, only use the ratio that is needed, not the 50/50 ratio.
I do think the "water wetter" additives do work. Like ethylene glycol it doesn't actually lower the temp itself, it helps the water lower the temperature.

[turbo69bird]

Originally Posted by 67drake

My GTO has been running hot the last few times I took it out. The faster I drive the higher the temperature creeps up, even just driving around with no hard acceleration.
So figured I’d start with the basics. The coolant that’s in the car is what I put in there back in ‘08 when I dropped the newly rebuilt engine in. I figured it’s long overdue for a good flush of the block and radiator.
Instead of refilling with the 50/50 mix of antifreeze and water, I’d try Water Wetter. I used it back in the 90’s on a hot running car, but don’t know if it actually helped or not. My cars now stay in a heated and A/C shop, so freezing in the winter isn’t an issue.
So, anyone using Water Wetter? Did it help cooling? Anyone hate it? Why?
Thanks!

First thing to do w any car running hotter as it goes faster is richer it up because it’s most likely lean. . Then address the cooling system . Plate to divider setting, make sure there’s a spring in the hoses to keep them from collapsing at speed. (They’ll suck themselves closed up) . Pretty sure Water wetter is just propylene glycol .