Team Camaro Tech banner

Working together or causing a problem?

951 views 7 replies 5 participants last post by  cerrem 
#1 ·
Please read the hole thing before jumping to conclusions please.


Really don't know how to start this but here it goes. I want to know if my electric fan sending unit on/off temps could be interfering with the operation of my thermostat. The temperature should remain fairly constant after the engine is warmed up.

I have 180 degree thermostat , and I have verified on the stove that it opens at the rated temperature.

My sending unit for my electric fan is in the driver's side head and is set to come on at 195, off 180.

Right now I have the temp gauge sending unit in the passenger side head just to monitor when the fan comes on and goes off. I do know that there can be some differences in temperature between the two heads but the fan does come on at 195 and turns off at 180 like it should. I am going to put the temp guage up in the intake. I also know there is a difference in temperature at the intake and at the heads for obvious reasons.

Given the 180 degree thermostat rating and the fact that the it is not fully open until 15 degrees above the rating and fan on/off temps, it looks to me like there will be good temperature fluctuation. What do you think?




------------------
68 RS, Ash Gold,pwr brakes,pwr windows,Hounds tooth,355/T350,MSD 6AL,3200 stall Dynamic converter,3.31:1 posi,Autometer guage pod
 
See less See more
#2 ·
I think your thinking too much about it


I'm not 100% sure what your asking


Did you get that vac leak fixed yet? If not, you need to hurry so you can come over and help me put the new leaf springs and rebuilt rear end back in the nova
 
#3 ·
I think what I want to know is the fan coming on and going off at the right time and not affecting the thermostat that much.

I just want to keep my engine temp somewhat steady. I want to make for darn sure I beat the heat soak problem that has been plaguing me since I bought the car. It may be the wiring if it does it this summer.

Checked around and can not find any vacuum leaks Travis. Just let me know sometime and I just might be able to free myself from the dreaded honey-do list and can help you.


I probably am thinking to much into it but that is just me.

------------------
68 RS, Ash Gold,pwr brakes,pwr windows,Hounds tooth,355/T350,MSD 6AL,3200 stall Dynamic converter,3.31:1 posi,Autometer guage pod
 
#4 ·
The fan won't effect the stat directly, it should open when it's temp range is reached regardless if the fan is on or off. You probably already realize that though. The thing I don't like about electric fans is it's designed to react to temp changes. so now your cooling system has 2 points of regulation, the stat and the fan. The reason for the fan is to augment air flow. You need more air flow when the car is moving slow or standing still. You can control the temp that the fan comes on at but it would be better to conrtol it based on the cars speed. what you end up with is a system that goes up and down between the stat temp and the fan setting.

As an example my stock 96 SS ( don't know the temp when the fan comes on) will run just above 170 when the car is moving but at a light it climbs to 210. Never goes higher so I don't worry about it. Well it's a rare day that I don't use the air so it took a while for me to see this and was startled the first time I did. With the air on (a/c on = fan on all the time) it stays just above 170 idleing or moving.

What I have concluded by all this is that these modern cooling systems are not as well designed as the old belt driven fan systems of days of old. Electric fan systems use all the tolerences alotted it do their job. when do cars tend to over heat? Summer, when folks are more likely to be using the air conditioning!! Well the fans on all the time then so that takes care of heavy duty cooling needs. The rest of the time it keeps things at a peak of 210-220 and the mill will live so the design gets the stamp of approval!!! When I first got the 96 I visited the LS1 and SLP sites and couldn't believe all the cooling problems the newer cars have. IMO it turns out it's not a problem it was designed that way, don't like the flucuation in temps turn your air on or run the fans full time or at a temp just below the stat temp which will allow the engine time to warm up before the fans come on...

Hope that helps...

------------------
...Dennis
"The '69, the '96 & the club"
 
#5 ·
what hole thing?


------------------
67 prostreet BB Camaro
71 BB SS Chevelle (clone)
2002 35th anniv SS Z28 conv.
 
#6 ·
I believe that the only way you will beat the heatsoak is by incorporating an electric waterpump with a tick tock switch. There is no way you will cool down an engine after shutdown otherwise. I think I understand what you are going after. I dont think it can be done anotherway. If a normal heatsoak period is causing some problems,I suggest looking at those problems You will likely have more luck curing them than you will eliminating heatsoak. My 2 cents.
Milan

------------------
67 prostreet BB Camaro
71 BB SS Chevelle (clone)
2002 35th anniv SS Z28 conv.
 
#7 ·
It isn't really a problem as much as it is a question. Put a heat sheild on late last summer and a new solenoid and it seemed to help the heat soak so I am not worried about that at this point.

I'll figure it all out.



------------------
68 RS, Ash Gold,pwr brakes,pwr windows,Hounds tooth,355/T350,MSD 6AL,3200 stall Dynamic converter,3.31:1 posi,Autometer guage pod
 
#8 ·
Engine cooling can be a royal pain.....
It is good that you used hysterysis in the temp range...this keeps the control system from oscillating...
Just a few suggestions for your cooling system...I did plenty of thermal engineering in the past..
Most modern day cars have a typical setting like this:
215 fan ON with 210 fan OFF....
43 MPH and less fan ON....
48 MPH and above fan OFF...
It will turn on at high speed ONLY if temp is 230...
ON with AC of course...
These temps are for emmision purposes..
These temps are way too rediculous for muscle cars....you would induce detonation at those temps with pump-gas and a 10:1 motor for example....
As a general rule you want your temperature switch swing to be above the thermostat temp about 10 degrees...But thats with a system that detects your speed...
If your electric fan is running at highway speeds the natural air-flow forces will work against the fan and will increase the load...this could reduce the life of the fan..
If your electric fan is against the rad and has no shroud...then you have no chance of cooling it right...
The shroud is key to getting the correct LFM across the ENTIRE surface area of the rad..
I would recomend the shroud with a stock fan blade ..make sure blades exceed into the cover of the shroud to some degree..
Regards
Chris
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top