Re: Overheating

Posted by Mike On 2010/12/6 9:39:25

Quote:

I have to respectfully disagree with you there.

My straight 8 288 50 Packard would idle all day in the summer heat and never puke or complain. It was great until the water pump went and then you started to notice it at low speeds, and then eventually even the highway wasn't enough to keep it cool. We'll see how the new 327 does, it's cooling passages weren't quite as clean.

I have a 71 pontiac that will idle all day with the A/C on at the car will run at whatever thermostat you throw in it. Even a 160. Granted, i made sure i had the larger crank pulley and the smaller water pump pulley and aluminum radiator and 7 blade fan and high flow water pump and the exhaust is free flowing and fuel mixture was spot on. The point is though, that even stock that car would idle at 200 (pontiac wanted the temp at 205-210) all day in the heat. Now it has a 195 thermostat in and runs at 200 all the time (i bumped it up to run warmer for more fuel and engine efficiency.)

I had a stock 91 GMC truck with no thermostat. It had slightly higher than stock compression, but that would add to heat issues. When i first met my wife, she would enthusiastically go on parts runs with me. We went out one night, the firs really cold one of that year, and drove 2 hours each way to pick up a rear end. The truck NEVER got warm enough to even try to heat the cab....We sat in 20 degree weather for 4 hours, stopping at gas stations to warm up. Don't know why she married me I never did get that truck even up to 100 degrees until i put a thermostat in.

Now, some vehicles with no thermostat will run away heat up, where you can't keep them cool because the water moves through the radiator too quickly.

Any newer car (80s and up) should have no trouble idling in summer heat if it's in good running condition, especially with electric fans to keep everything cool kicking on and off, and with such smaller and more efficient motors.

Again, i have NO experience with V8 Packards. And i know in STOCK form, yes, you might not get certain vehicles to idle in summer heat and not cook. That's a mistake of the original engineering in my book. There are small things you can do to help (overdrive pulley sizes, fuel mixture) and major things you can do to help (great radiators, up the exhaust size, find a high flow water pump) but it all comes down to the fact that almost any motor can be made to run cool under almost all conditions, and i have to believe that for the Packard V8 as well unless there is some large design flaw in the block somewhere. I don't want a car that i start and move to the driveway and then get an emergency phone call or something happens and i don't get a change to watch it for 20 minutes and come back to find out i cooked it.


Now i agree that if it's not showing symptoms of overheating, then it's likely not and it's the gauge or our perception of how hot is too hot might be off. But as far as saying that it should overheat from just sitting still in the heat, i would investigate to see if i could eliminate even that. A more efficient motor is a happy motor and the car would thank you for it.


Edit: I would like to point out that i was always told letting a car idle for a long time would promote cylinder wash down from the fuel and lower oil pressure and lead to cylinder/piston ring/piston wear. I don't know how true that is. I definitely have let some cars idle for more than an hour while i work on them or tune them. I wouldn't recommend letting any car idle for 3 hours just to test it's idle cooling. I would think half hour to 45 min would be more than enough to get up to temp and see if it stays there.