#21  
Old 12-16-2022, 12:56 AM
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Laws of physics being what they are ... the heat has to be going somewhere.

Would a blocked bypass cause excess pressure under the thermostat?

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  #22  
Old 12-16-2022, 08:06 AM
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Quote:
Originally Posted by dataway View Post
Laws of physics being what they are ... the heat has to be going somewhere.

Ya, I completely agree. Only thing I can think of is it's bypassing at thermostat. Easy check like OP mentioned. Hold your hand on radiator inlet. Next is maybe heater core removing heat enough while engine idling.
When the stat is closed the only circulation is in the block and heads and heater core. I guess if you have enough cold air going over the block with Radiator fan it will keep temperature down as it's removing heat around the block. You must just have a very efficient setup there.

Next time you run it in cooler to cold weather at idle stationary, put a large garbage bag across the front to reduce the cooler air being sucked in across the Rad/Engine. Just make sure to secure plastic bag so don't get caught in fan blade.

I've had to do this on my car in cooler weather to bring it up to 160* (Just idling in driveway.)The flex-fan was keeping the engine temp down also. So, your probably fine with everything.

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  #23  
Old 12-19-2022, 01:44 AM
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Well yesterday I got a little time before I had to pick up my daughter. Drained the system enough to remove the upper hose and stuck my finger inside the water neck. The thermostat wasn’t totally tight, as I was able to turn it an eighth to less than a quarter turn but I wasn’t able to lift it so although some fluid probably seeps past I wouldn’t expect it would be enough to take much heat with it.

I ran the engine in the driveway for about 20 min at fast idle then another ten or so at idle. Never felt the upper hose get hot to the touch. Just warm at best. Engine temp hovered around 160°. Maybe a bit higher at fast idle but no more than 165-170°. I didn’t have time to block the radiator to see what happened and no test drive as they salted our roads recently.

The thermostat must be opening otherwise the engine would be overheating I would think. I’d also like to think, like someone mentioned, that my cooling system is just very efficient. I just wish engine temp wouldn’t start creeping up with the air conditioning on at idle in hot weather. A also have a heater hose close off valve that was open save for the last 5-7 minutes. No change when I closed it. I suppose I have a non-issue overall. I appreciate the input however. Just seemed to run too cool in this weather.

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  #24  
Old 12-19-2022, 03:07 AM
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The e fans are nice for the summer. Took a set from a 4th gen and put them in a aluminum shroud. Have yet to over heat it even out here.


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  #25  
Old 12-29-2022, 12:03 PM
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I'm in the same boat as you, my friend. After I went overkill on overhauling my cooling system last year due to just a couple of incidents where it crept to around 215-220 during idling in the summer (I think it was a slipping water pump, since the temp creep would only happen after I had belt chirp when gunning it to 3500-4000 RPM; found out I had offset pulleys and a faulty reman alternator); now my car runs ridiculously cool. It's a cooling system most people would put on a high HP build, but on my low-ass compression 400 lol. I think I've described it to you before. The only time I ever see the temp needle reach the first 160 degree peg is when I bring it onto the highway and let the RPMs heat up the engine or when I'm running AC (which I rarely do), but even then it it stops right at the the 160 mark or maybe half a millimeter past it on the gauge and doesn't move from there. On top of that, I can drive the car for over an hour and when I shut it off, I can grip my hand and hold the radiator hose right at the thermostat housing and not get burnt/hurt. And if the temps dip below 60? Forget it - if I'm driving around town, the gauge doesn't seem to go past 140 and I can literally touch my hand on the front of the cylinder head after an hour of running and not get burnt. In fact, if I'm just granny-driving around town on cold winter days, the oil pressure will start to go back up as I keep driving around since the heavy duty fan clutch transfers a ton of heat, and combined with the cold ambient temps, the oil probably starts thickening again even while the car is running.

The way I look at it, people complain and have so many problems with these motors running hot, I don't have much room to complain if mine's running cool. Especially since I live in South Florida. I'll need this efficient cooling system in the summer.

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