Coolant level controlled fan or shutters

[user removed]

Also a pressure switch could be easier to install in recovery bottles that are pressurized.

regards
Mech

[RedDevil]

I'm sure this has been discussed before (said the thief ) but how about exchanging heat between the flow to and from the radiator?
Maybe by using a heat exchanger but have both flows in the same direction, as to mix (instead of surpass) the temperature to the rad and to the engine?

Then the radiator would warm more evenly and the backflow will not be cold.
If it gets really hot the radiator will pretty much get fully heated anyway.
If the engine is cold some of the first heat flowing towards the radiator will flow back into the engine keeping it in the comfort zone.

[user removed]

Most systems have a bypass circuit that allows coolant to recirculate during warm up. The thermostat opens when the temp gets up to normal, but coolant is circulating through the engine even when the t-stat is closed.

I believe that the problem of overcapacity in cold temps should be approached
by a method that reduces the "effective capacity" of the radiator itself, which means blocking the grille to restrict airflow. This controls the capacity of the cooling system to remove heat from the engine, but would not have any effect when any situation would require that greater capacity to be utilized.

Coolant level changes are precisely relative to average system temperature. Even a 1 degree change increases the coolant level. This allows precise adjustments of air flow over the radiator to maintain that average temp within a few degrees regardless of the weather conditions.

regards
Mech

[RedDevil]

The bypass will most likely end up where the radiator return feed is, so indeed for the engine there is no gain in my concept.
But there is a benefit for the radiator.

The heat exchanger (heat 'mixer' would be a better description) makes the engine receive warmer water from the radiator; as a result the engine temp would rise so the thermostat will send more coolant to the radiator instead of the bypass circuit.

So heat exchanging will increase flow through the radiator.
It will also bring down the temperature of the water flowing into the radiator, so that heats up more evenly.
These effects both reduce thermal stress on the rad.

It will also prevent the buildup of pressure before the whole radiator is hot; even if the water leaving the engine is above boiling temperature, the drop from the exchanger will bring it down unless the reflux is boiling hot too.

In short; this would solve the uneven heating of the rad under low load but retain full capacity when needed.

This is not a substitute for active grill blocking, but could be a useful addition.
It will definitely make the system less critical to which method is chosen to switch the block.

[samwichse]

How about just measuring the difference in level rather than the set level.

IE: your float must have a pot on it to send its level to... whatever (arduino?). When you power it up take the first readings as the "cool" temp, and then average it with the last 5-10 cool reading levels (in case you warm-started, that running average would save your bacon).

Then your louver opening/fan on temps would just be a certain level above this... to be experimentally determined. You would only run into issues if your coolant bottle went completely empty, but you could even add a check for that in your ardy code if you wanted (if the initial value is less than ____, turn on an LED).

[Cobb]

I dont know, maybe its me, but either psi or level seems it would vary with water content in the fluid as well as the vehicle location to sea level.

How about measuring temp at the t stat to get a better reading or cylinder 1 where coolant typically enters an engine? I use to work in a machine shop and cylinder 1 was always the least distorted and the last cylinder where the fluid exited was the most distorted.

On many cars the temp sensor is either on the other side of the t stat or the throttle body. In many cases it the t stat can fail and your sg2 or analog gauge says cold.

[sjgrimsley]

To maintain a specific engine coolant temp, isn't the coolant absorbing the same amount of heat energy, only with varying volumes of coolant? (I.e. Thermostat)

[Cobb]

Good question.I know in highschool we use to say ice made things colder. The prof would say it absorbs heat.

Well for a while as it opens it introduces cold coolant from parts of the car it was not circulated through like the block,heater core, then radiator. Then as those start to warm they radiate heat and provide more cooling.

Owning a scan gauge is fun to watch water temp. I use to dirve from a dead stop 43 miles. I notice I never got to operating temp but it constantly went up and down. If I got a stop light, just one. I would achieve operating temp and it would only go down maybe 3 degrees the rest of the trip.

Furthermore when I am in traffic I see up to 203 when the low speed fan kicks on. Once it seems heat soaked I never see it go below 185 for duration of that trip. .

Originally Posted by sjgrimsley

To maintain a specific engine coolant temp, isn't the coolant absorbing the same amount of heat energy, only with varying volumes of coolant? (I.e. Thermostat)

[sjgrimsley]

With my car, coolant constantly circulates from radiator to engine block to heater core and back to radiator, no matter if the thermostat is opened or closed. This 406 heats up to operating temp fairly quickly even in cold weather (195° thermostat). When I data log with my laptop it will usually show about 190° unless it's over about 80° ambient temps, then it runs up to 205°. I blame the variation on the simplistic design of the t-stat.

Anyway, before the 406, it had the factory 305, which in the winter time would require blocking about half the radiator with cardboard, otherwise it would never reach operating temp.

I think (I could be mistaken) every engine is designed with a t-stat bypass to maintain a minimum flow of coolant thru the engine to minimize hot spots from forming in the water jacket. I guess sometimes the weather is cold enough the engine can't generate enough heat to soak the cooling system, so it never overcomes the heat loss from that bypass until you come to a stop and let the heat soak happen. Just my estimation.

[Mista Bone]

Your original 305, the electric cooling fan(s) wouldn't kick on until 235-240...which was known to cause starting issues on the later TPI motors.

I had an 86 WS6 TA, 305 TPI Peanut Cam, used to be on Thirdgen.org.

I even have articles from Car & Driver about the Gale Banks 200 mph speed run.