Hey guy's, I'm back,,,, So the .30 over 455 I built for the 442 clone seems to run little warm around 200 deg F, that's with a new 180deg thermostat, 4 core alum radiator, timing set around 12 deg, (wont start with anymore timing cause comp) and a electric Ford Taurus radiator fan. Just curious to what every ones temps run on their 455's

 

I have the same engine .30 stock except a few outer mods and mine run at about 170-175 I drove it last night at about 55 degrees outside until it quiet on me. You would have to read some of my threads to know why and advise would help

 

I'd add a bottle of water wetter to your cooling system. Is the 200 degrees while moving or standing still at idle?

 

quiet or quit? guess they both mean the same thing, lol. WOW 175deg? that's kinda unbelievable to me for some reason, Hope you get it running again.

 

No snake oil yet, I mean the water wetter yet, lol. around town and in traffic it runs round 200F, Hwy runnin its still round 190F.

 

The water wetter will drop the temp down 5-10 degrees. Make sure you have all shrouds in place and the air is directed through the radiator. 190 at hwy speed and 200 in traffic or slower speeds is fine. Remember your thermostat starts to open at 180 and is fully open at a bit higher. Make sure your water level in the radiator is correct also.

 

190 to 200F is ok? OK, just trying to find out where these olds run at temp wise, what would you consider redline on temp, personally I draw the line at 230deg, that's a shut it down to me temp.

 

counter intuitively try a 190-195*F TStat. Reasoning is the coolant isn't spending enough time in the radiator rejecting heat. It will then dump it right back in to the engine. The 190*F stat will allow more dwell in the rad for full heat rejection.
Under what conditions is the 200*F occurring? Highway, city, idling? 200*F isnt all that bad if the car isnt moving and the engine is a fresh rebuild. Is everything else in place; air dams, fan shroud, radiator to core seals...etc...
Look in to Stants HD series stats. They have better temp regulation.

 

220-230*f

 

Idiot lights come on at 250-260.

 

That is not quite how it works. Faster coolant flow through the radiator = more heat transfer based on the laws of thermodynamics. That's why Heavy Duty cooling engines had a pulley setup that ran the water pump at a faster speed.

 

just a thought - are you certain that your temp gauge is giving an accurate reading?

From the difference in city/highway temps it sounds as if you may not be getting sufficient air flow at lower speeds.
A few things to check:
1 - shroud installed and properly sealed around radiator
2 - Fan clutch (if installed) working properly
3 - Distributor vacuum advance connected and working properly

 

I understand where your going with the thermostat and it is a new elec temp gauge, I also have a laser hand held temp reader, My real question was asking what other peoples temps run in their cars?

 

I'm sorry, but I can't let this pile of internet-amplified nonsense go by without refuting it.

The reason why it is "counterintuitive" is that it's wrong. It involves no "reasoning" at all, and defies the most basic laws of thermodynamics.
It's as nonsensical as saying that cold water boils faster, or hot water makes ice cubes faster.

I will not re-type information that has been discussed in detail on these boards a number of times in the past, but will provide links to the information here (RIP, Norm ), and, especially, here, as well as to a link regarding antifreeze efficiency and WaterWetter.

If I were the king of the world (or at least the forum), I would delete posts like this as soon as they appeared, just to reduce the risk of the contagion spreading.

- Eric

 

As I stated above with the Waterwetter a 5-10 degree drop was realized. I use it in my car and it works. There have been a great many documented tests performed with it which is why I tried and suggest it.

 

I wasn't arguing about the WaterWetter, Eric, only about the idea that faster-moving coolant doesn't cool as well as slower-moving coolant (which is the opposite of the truth).

I agree that WaterWetter works, by acting to decrease the surface tension of the coolant, and thus better coat the inside surfaces of the water passages, thus enabling the coolant to pick up more heat. I suspect that it also increases flow in the layers immediately adjacent to the layer that is against the surface, thus also improving heat transfer.
The information in the thread I posted demonstrates its effectiveness. I'm sorry that I didn't make that clear in my post (but, on rereading it, I can see that I didn't).

One thing to remember about WaterWetter, is that it's supposed to be used with water alone (as water is more efficient at transferring heat than antifreeze is), and not with antifreeze, which has its own surfactant properties to reduce surface tension.

- Eric

 

All I was asking for was what does everyone's temp's usually run in their olds, This was my first olds build and you guy's are pretty much all I have to go on, don't think anyone actually read my post, lol

 

My temp usually runs right at the thermostat opening temperature.

The only exception to the above is 70+ MPH highway driving with the AC on in 110+ ambient temps, then the coolant creeps up to 210+. Slowing down to reduce engine speed below 3000 RPM results in coolant temps dropping to 190 or so.

 

Im having the same problem with my 350 I have electric fans on it I have a 160* tstat though , upon cranking it and allowing it to sit and just idle it will get up to 180* in stop and go traffic 195*-200* and the top radiator hose gets hard as a boulder it will drop as someone said at low rmp driving. 175* thats completely unbelievable I've never known an olds motor to run that cool you would have have to run 2 radiators to achieve temps that low(which is impossible) I'm trying to find a way to bring it down to at least 180*-185*I'm getting so frustrated with this temp that im seriously considering selling this vehicle.

 

As oldcutlass said, idiot lights come on at 250/260. When I bought my Cutlass I read somewhere in the Service Manual or some other Oldsmobile document that the normal operating temperature was 200 degrees. So many people, myself included, are obsessed with keeping the coolant temperature below what the engine was designed to run. We add huge radiators, extra cooling fans, super heavy clutch fans to run below the designed operating temperature. Too cool can lead to problems too, especially on short runs.


I read an article in a magazine recently. A reader asked why new cars seem to run at constant temperatures, where old cars had more temperature fluctuations. The answer surprised me. Apparently newer cars are designed with temperature gauges that are less sensitive to moderate temperature changes. They tend to average the temperature so the gauge doesn't move unless there is a more severe change. The reasoning is that many owners get concerned when 200 goes up to 205 or 210, when in stop and go, or coming off the interstate or whatever, and think they have a problem when that is just normal temperature fluctuation.


More, or less in the case of temperatures, isn't necessarily better.

 

Spyke your temps are normal, people install gauges and then get all worried about temps and oil pressure. Drive and enjoy your car.

 

+1, and that's what it's supposed to do.

I've had ones that were hard to keep cool (and not only Olds), and, honestly, I never figured them out - they were just cars I drove for a while, then sold. My guess is that they had a lot of sludge and corrosion inside the engine blocks, as I had replaced radiators, thermostats, and water pumps with absolutely zero effect.

It drives me crazy when a car's temperature goes above the thermostat set point under ordinary driving conditions, and the reason it does is that it happens to me so rarely.

Anyway, to answer the OP's question , 195° is the recommended temperature, 200-210° should be fine, 180° is fine, 160° is probably too cool.

- Eric

 

My old 30 over 455 ran 210 in traffic, 190 on the hiway. With a 185 stat

 

Using this post as an illustration, allow me to point out that temperatures in traffic don't matter, as they are a function of your fan, shroud, fan clutch, etc., and not of the rest of your cooling system, provided that the temperature goes down when you get moving (as in this case).

If your temp goes up in traffic, then, yes, a better fan or fan clutch, or maybe an additional electric fan might help.

Remember that sitting at idle, the engine produces very little heat compared to the amount it produces pushing your car through the air at 70mph, so if it stays cool on the highway, the only reason it's not staying cool at idle is airflow.

Saying you run 190° on the highway with a 185° thermostat is the same as saying you run 185°.
There is no difference.
5° is 3% of 185°F (or of 190°F).
5° is less than 1% of the 3° difference between 358°K (or 361°K), which are the same temperatures in absolute terms.
What do you think the tolerance standard of a thermostat is? 5%? 10%?
How about the tolerance of a temperature gauge?
If you ASSume a tolerance of 5% for each, which is a very close tolerance for commercial products such as these, that means that at 185°F you can be off by 9¼° and still be within the specified tolerance of the product. That means that you can end up with a temperature reading anywhere between 166° (thermostat and gauge both at low end of tolerance band) and 203° (thermostat and gauge both at high end of tolerance band), and still have the thermostat and the gauge working within their design parameters.
In average use, both the gauge and the thermostat will of course be closer to the middle of their tolerance bands, and quite possibly not in opposite directions (cancelling each other's errors), but the fact is that with a 5% tolerance, which is fairly tight for consumer goods, you can have a legitimate 40° variation in temperature readings.
If that seems unrealistic, try a 1% tolerance (which really IS unrealistic for consumer goods of this type), and you'll get a tolerance in readings of +/- 3.7°F, or a range of 181° to 199°, which is an 8° band.
What's my point? If your gauge is within 5° of where you think you want to be, it's as good as perfect, and within 10° is probably fine, too.

Don't sweat the small stuff.

- Eric

 

Aftermarket electric fans are notorious for not pulling enough air across the radiator, which results in the engine running hotter. Do you know the air flow rating (CFM) of your fans?

As I posted above, my engine runs right at 180-190º and I drive in 115+ degree summer temperatures. I have a copper/brass 4 row radiator, the factory mechanical fan, thermostatic fan clutch, and shroud. If my cooling system can work in 115º and hotter ambient temps, then folks in cooler climates should be able to keep their engines from overheating.

FYI, back in the '80s I removed the thermostat and my engine ran at ~130º no matter how hard I dogged it, even with the AC on. What this means is the cooling system was working well enough that it could dissipate all of the heat that the engine was producing, and then some.

This is how the system is supposed to work, but if there is an imbalance in the system (engine producing more heat than typical, radiator cooling capacity too small, coolant flow restricted, air flow across radiator restricted) then the heat can't be dissipated easily and operating temps go up.

 

Ok then why does the upper radiator hose get so hard is that normal

 

Very normal, the pressure moves the boiling point higher. You have anywhere from a 6 - 20+lb rating on the radiator cap.

 

Like Eric says, Yes.

Have you ever owned any other cars?

I ask because all cars made since about 1960 have at least 16psi radiator caps.
Cars made in the last 15-20 years have 20psi caps.

Therefore all cars made in the last fifty years or so (with the exception of Volkswagens, which use uncle-freeze) develop at least 16psi in their cooling systems when warmed up, and all of their hoses (upper, lower, heater, all of them) get hard when this happens.

You should read the information I linked to earlier.

- Eric

 

.
To answer the original post, my 70 442 runs at 180 +/- 5 degrees.
On the hwy, at the track, in traffic. It has the original 4 row, factory fan and clutch. And the pulleys and w/pump impeller were designed by gm engineers for that car with that engine/gear/trans combo.
I've never driven in more than 100 degree heat, but no doubt there is cooling capacity in reserve.
Always keep in mind that it is a cooling SYSTEM. Changing the rear gears can adversely affect that system's performance.

 

Moderator, MDmechanic's posts on this thread should be a sticky..

 

Ha ha. I thought you were going to say they should be deleted.

Thanks.

- Eric

 

Well I took the car to the track today just play around a little and along the way I was running 65-70 and the hose to the heater core busted the top and bottom radiator hoses are new but the heater core hoses were old that couldve caused it to blow im really considering selling this car its a 70 model 4 door in good condition with the original 350 rocket and has 45000+ miles all the glass is in it its very solid black with Grey ralley stripes and 22" rims I am really looking to get rid of it im asking $3700 or I'll let it go for a 2door chevy malibu and $1500 or make a deal I cant refuse I can be reached at334-327-6362

 

Wouldn't your post fit better in the For Sale section?

 

I don't see why your going to sell your car. It is doing what it's supposed to do. The heater hose bursting is coincidence due to an old hose, it happens. Mine did it last year when I went to meet a CO member in another town. I repaired it in a Barbque restaurant parking lot.

 

I didnt know that there was a for sale section the only reason in want to sell it is because I like dealing with chevy motors I have a 79 monte carlo and the heat never rises above 185* I can run it as hard as I want raise the hood and squeeze the hose like a sponge olds moto Rds scare me I l Ike to travel alot 3 to 4 hour drives 8 dont like feeling like at anytime a hose is gonna burst now I know what happened tonight was because of old hoses I just by passed it and filled it with water and kept going. Where can I find this for sale section at.

 

The Cars for Sale section is here.

And if your Monte's hose is soft when the engine is warm, there's something wrong.
Probably a bad radiator cap.

- Eric

 

Dayuum, What did I start? lol. Oh yea, The Edelbrock intake that's on the engine is also plumbed to vent rear of cyl heads on both sides and (Y's) to the heater core and then dumps back in radiator like chevy truck and front metal horseshoe bypass is halfway blocked.

 

Sorry bud but all pressurized cooling systems work the same way. The hoses will get hard when the engine warms up. All engines operate in the same temp range.

 

If the rock-hard hoses bother you, install a 7 PSI radiator cap.

 

A 7 psi radiator cap? Excuse me cor sounding dumb but what is that ?where can I pur hase one ? And what is that gonna do for my hose?