Normal Operating temperature with aluminum RPM heads?

[Myasylum]

I was just wondering what the normal operating temperature should be for a Big Block 400 with RPM aluminum heads.

I have read that aluminum heads do have a tendency to run hotter than Cast Iron. However, mine car seems to run around 220 degrees. To me that seems hot.

It sits pretty steady at 220 and seems to be pretty content there, and where it seems too "live". It may go a few degrees warmer or cooler depending on traffic.

You think 220 to hot?

Thanks!

 

[Runcharger]

Depends on your gauge. Aluminum sheds heat faster than cast iron so it should actually run cooler. I always run a 195 thermostat to keep the engine warm for peak efficiency.

 

[Myasylum]

I was thinking about flushing the coolant and getting a new thermostat. With environmentalist these days is not as easy to do as it used to be. I don't even know who takes old coolant?

 

[Don67Satellite]

To me, 220 is not normal at all. Sounds like possibly not burped properly and you have air in the system.

Google "recycle antifreeze near me" or something. Sometimes the drive-thru oil change places take fluids, or a local recycling place.

 

[Paul_B]

My engines run around their thermostat temperature or just a bit higher on a hot day. 220 is on the warm side for anything older that I’ve run.

If your thermostat is bad it can make it run too hot. I’m not sure if a coolant flush will make a huge difference. How good is your radiator, cooling fan, and shroud? Is your gauge accurate?

For your old coolant, there is one parts store in my area that I’ve heard will accept old coolant to recycle. Some municipalities have a special event day where they allow residents to drop off unwanted chemicals such as coolant for proper disposal.

 

[Kern Dog]

The county dump takes "hazardous" waste for free.

 

[Myasylum]

Yea, I looked up "recycle antifreeze near me", and O' Reily's came up. Didn't know they took old stuff, or maybe it was just a car related thing that popped up. I'm going there anyway today. I'll ask them. If they take that stuff great!

I'll try to burp the system first. You just let it run with the cap off, correct?

 

[69ChargerR/TSE]

I'd suggest Evans waterless coolant

 

[hunt2elk]

220 is to hot imo. I have 2 400 based strokers with factory 22 inch radiators redone by Glen Ray. Bot cars run between 180 - 190 depending on outdoor temps. Did you verify your 220 with a temp gun?

 

[Kern Dog]

I'd suggest Evans waterless coolant

Absolutely not.
Way too expensive and cannot be mixed with anything?

 

[Don67Satellite]

I'll try to burp the system first. You just let it run with the cap off, correct?

I use one of those special funnels and lift the front end a bit and let it run until all the air bubbles are gone. Using a standard thermostat, I also drill a 1/8" hole in it and that will allow any leftover air to escape.

 

[wagonman]

My 470 with TF 240s and a 180 Champion Radiator no shroud Hayden clutch 7 blade in 105 heat runs 180-190 200 in cruise traffic.

 

[eldubb440]

try a higher temp thermostat, it will keep the coolant in the radiator longer

 

[hunt2elk]

try a higher temp thermostat, it will keep the coolant in the radiator longer

I hear others saying that as well, but it makes no sense to me. Keeps the coolant in the radiator longer, but also keeps the hot coolant in the block longer as well. I say keep it moving. Good radiator, FlowKooler water pump, and a high flow 180* stat. Op still needs to verify that his gauge is reading correctly....

 

[eldubb440]

I hear others saying that as well, but it makes no sense to me. Keeps the coolant in the radiator longer, but also keeps the hot coolant in the block longer as well. I say keep it moving. Good radiator, FlowKooler water pump, and a high flow 180* stat. Op still needs to verify that his gauge is reading correctly....

saw it work for me....... 180 thermo wouldn't hold the temp down, would just keep getting hotter, tried another one with the same result......put a 195 in it, and it never got over 195......every situation seems to be unique, go figure

 

[eldubb440]

it's been years, but I'm sure I tried running no thermostat with the same hot result..... which got me to thinking

I daily drove the car for over a decade after that

 

[1KoolBee]

Sounds high to me. My Bee ran 180, even in 100+ temps around town. It would creep up to 210 or so with the air on. 26” factory 3-row radiator and factory HD clutch fan. It ran hotter with the original 2-row, but a 3 row junk-yard swap from a wagon cured it. Never overheated, ever. No weird coolants, no mega electric fan, no super cool water pump, no burping or anything like that. Just the stone-axe simple factory setup. Sometimes being a dumb kid on a shoestring budget was an advantage. I’d make sure your coolant flow is correct, start with simplest things first.

 

[davek]

1st hook up a mechanical gauge then go from there. My Bee gauge is 15 degrees off so I run both on it.

 

[Don Frelier]

saw it work for me....... 180 thermo wouldn't hold the temp down, would just keep getting hotter, tried another one with the same result......put a 195 in it, and it never got over 195......every situation seems to be unique, go figure

I ran my Plymouth with no thermostat while I was flushing it out.
I don't think it got above 150 degrees.

 

[eldubb440]

I ran my Plymouth with no thermostat while I was flushing it out.
I don't think it got above 150 degrees.

I remember looking in the radiator and the coolant was moving like a hundred mph....... in the spirit of full disclosure it was an AMC 390