Streetstuff

My temp gauge says 210° after a 20 min drive when its ~80° outside, easy highway/city driving. It ran at 190° when it was ~65° outside on the highway for an hour. Turns out I don't even have a thermostat?!?. I think the radiator had stop-leak in it because when I flushed the coolant, scum colored "flakes" came out. Whatever it was it looked like it had been stuck to the inside walls. Any guesses? Still plugged? Bad water pump maybe? Too small of radiator (1.5" thick)?

Bob88GTA

iTrader: (2)

Take the radiator out and have it "professionally rodded out" They take the plastic ends off and run long rods through the cooling passages and get all that stop leak crap out. That's the worst stuff in the world for radiators. They will boil it and put the ends back on. Best 60 bucks you can spend.
Also make sure your air dam and shroud (if you have one) is in place.

Hopefully you water pump didn't fail from all that stop leak. Just my suggestions.

Ron U.S.M.C.

I totally agree with the statement above but......What do the fins look like on that radiator. What color are they. Folded over and brown from where and tear.
If that's the case just put in a new stock replacement made by Murray.= $89.99
Nice and new and shiny and works well with the right fan/fans/thermostat.
Anyway, a car will not necessarily run cooler because of a lack of thermostat. The coolant needs time to cool off within the radiator. Having it move at a high rate will not help. 180* is my suggestion for a thermostat.

Streetstuff

Thanks guys, I completely forgot that the coolant could be moving too fast thru the radiator so I'll buy a thermostat first. The radiator itself is in good shape, all clean silver and only has three small dings in the front.

Streetstuff

Ron, how hot does it get when you get on it? I'm just worried I'll get too hot in the summer.

P.S. if you want to type the degree symbol hold Alt and type 0176.

Ron U.S.M.C.

We have really nice weather here all year long (wine country) It hit 100* here today though and even in heavy traffic the car would not get any higher than 190*/200*
Granted I'm not pushing any real HP but on this site I've heard it said many times that a stock radiator with the right fan/fans and thermostat will support most moderately beefed up 350,etc. very well.


The set up I created using a 14" puller and a 16" pusher with adjustable, temp. controlled fan switches and set in the lower 180* range. I also have large engine oil and transmission oil coolers installed. I'm pretty sure it will handle the 350 I'm looking forward to.
Also, I don't care how many rows a radiator has it still all boils down to the air being pulled through.

killer777

Stock operating temperatures for these cars are about 220*. I would get it flushed. Get a tad cooler thermostat in, but don't go for the lowest if you drive it in winter, or you won't have any heat. And I would get either a temperature control switch with sensor/ prob, or a chip you can take out in the winter that will activate the fans sooner.

deadbird

(edit) oops.

Streetstuff

Got a 195° thermostat from O'reilly today, but I had to leave for work so I'll test it out tomorrow.

Streetstuff

Runs a very consistent 212° except at idle which was above 220°. How hot do you guys get after shutdown? I got to a little above 240°.

Ron U.S.M.C.

Sorry but 195* thermostat is a stock setting that runs with the IMO very high stock fan settings starting with 222*.
You will never bring your cars running temperature down with that.
You will need a 180* thermostat and that is a "middle" temperature setting that I personally think is perfect 99% of the time and its what I run.



Then you will need the fans to come on close to that temperature.
With that configuration you should be keeping the car in the 180* to 200* range.
Its easy to do with adjustable , temperature controlled fan controllers'.



Do you have just the one fan ? If so I have the perfect fan set up for you costing around $ 25.00. Its soooo simple to do and it uses the stock wiring.


You can still use this with the duel fans .

Streetstuff

Yeah I wanted a 180*. I'll probably buy one sometime soon. I only have the belt driven fan so please do elaborate on the $25 setup. I've been thinking about electric fan(s) for a while now.

naf

iTrader: (7)

the 195 is fine, I wouldn't waste any more $ there. good average summer temps for your motor should hover in the 200-220 range. a lower rated t-stat won't change that.

the recommendation to simply replace the radiator is a good one. no telling how much scale and crap is in yours OR the condition of the fins.

install new rad and run antifreeze with distilled water. both help prevent corrosion.

seems to me if the coolant can move too fast through the radiator to cool down, it could also move too fast through the engine to heat up. following that thought process there would be some flow rate at which the temperature of the coolant wouldn't change at all...

actually the heat energy transferred is the important part and will stay essentially the same as long as the flow characteristics don't change (turbulence, cavitation, etc.).

as a (very) simple example, consider the heat energy transferred in one minute by a fluid with an overall delta T of 10 degrees at 10 gpm vs. the heat energy transferred in one minute by a fluid that drops 1 degree at 100 gpm.

Queball

my 92 RS, came with Fan running soon as you turn key on..i was running past 220° (mind you i live in Arizona)..so i run a thermostat 160° during summer time and 195° winter time here. works out fine for me. I didnt try the 180, i might do that n see if thats the happy medium. but for now..with running the AC and making trips to Phoenix Az.she runs cool..never goes past 220 with AC on..and fan constant running...one other thing i did was replace the Temp sensor..that changed alot on how my gauge was reading too.

hamster35

Something else to think about. The thermostat is to keep your coolant at a minimum temperature. Once it opens, at 180 or 195, it is out of the equation except as an orifice to control the speed of the coolant.

Ron U.S.M.C.

If you have a manual fan than as apposed to installing a electric one, test to see if it has enough draw to take ADVANTAGE of a 180* thermostat.
I dons see how a 180* thermostat can be compared to a 195*. I'm not an mechanical engineer but you don't have to be one to understand that coolant entering the engine at a lower temperature will keep it cooler than having it enter at a higher temperature.

Example = you can have a typhoon blowing through a radiator with a 195* thermostat and that engine will not get any cooler then 195*.
Same typhoon blowing through a radiator with a 180* thermostat will allow that same engine to run at 180*.
Unless he wants to run in the 220 range as opposed to the 190* range.

Wasting more money ? Were talking about $ 10.00 to cure his headache.

Sorry but this kind of stuff just pisses me off.
I don't like giving exhalent advice just to have it dismissed.

hamster35

I didn't say anything about you being wrong. Nor did say to dismiss your advice.
What I meant is that if your engine is running 210* with a 195* thermostat, don't expect a 180* thermostat by itself to make the engine run cooler.


Just something to think about.

Ron U.S.M.C.

Well if he has a fan that is coming on at 180* , and since his fan is mechanical its actually acting like at the very least a 170* fan, the coolant will be at 170* initially when it starts to flow through the 180* mark.. The 180* temperature is what's on the engine side of the thermostat .The thermostats flow is slow enough that it cools whats in the radiator to the 180* mark. Then the thermoset allows it to enter at that temperature. It’s a cycle that is continua's and is what keeps the engine at a cooler temperature than a 195* thermostat.

Just to be clear, I'm talking about the temperature of the coolant that the coolant temperature censer is suspended in.
That coolant temperature is what regulates the thermostat.
All being measured with a infrared temp. gun pointed at both the thermostat housing and directly at the surrounding area of the temp. censer.

Camarothatcould

iTrader: (3)

Stock tpi cars run hot, hell my first fan doesn't even kick on til passed 220. Sitting in traffic I'll see 230+ but once I'm noving, it drops

naf

iTrader: (7)

The biggest issue with running your engine too cool (provided the system can even keep it at 180) is that it may not get hot enough to boil water out of the motor oil. Trapped water causes acids and sludge. Water is a product of combustion and it WILL get into the oil.

The stock mech fan has a temperature regulated clutch and will essentially freewheel at engine temps below around 200/220.

mmadden55

Ron, I do have a single electric fan and I would be interested in your solution.

deadbird

To side with hamster and not discounting Ron, if there is a heat transfer issue within the block (rust scale, sludge), you could run ice water through the engine and it will overheat because the 'muck' is inhibiting heat transfer (muck insulates)

Another consideration, the impeller of the waterpump may be shot due to age/erosion (they do get less efficient over time) but, not leaking as a traditional water pump fail since the seal is still fine.

James Sutton

iTrader: (2)

I had a 190 thermostat, and my 91 Rs was running 30 degrees warmer. Turned out to be a bad torque converter.

Ron U.S.M.C.

I see. I was not familiar with the mechanical fan only spinning at a set temperature.
Sorry.
As far as water in the oil I've been running at the lower temperature of 180* to 200* for over 9 years now with not trace of water in the oil. I run 5w-30 EP Mobil 1 synthetic I change at 3,000 miles or 1 year what ever comes first. Usually just on my B-Day once a year.
Any way there are tons of guys here that don't like running there cars at 230*. I'm just one of them.
When someone says there car is running hot, I suggest the 180* to 200* range.
As far as the circuit for a single fan that wants to be adjustable ,temperature controlled for around $25.00 here's what it looks like. There is nothing simpler than this. You just place the controller on the ground wire going to the switch in the head. Remove the wire from the switch in the head and ground it.
Slide the probe in between the fins of the radiator about 3in below the top row.
Adjust the controller to have the fan come on when you want it to. Generally 180* to 190* and install a 180* thermostat. and your done.


There are 2 different circuits. This basic one for a basically stock fan using stock wiring. And another for a completely independent circuit that can support any fan including the large high amp motors.
You "do not" use the instructions that come with the controller.


Here's what the first circuit looks like. And a link to the controller.

http://www.autozone.com/autozone/parts/_/N-9pd8y?itemIdentifier=267187_69565_0_
Part # 733653

Ron U.S.M.C.

I have duel controllers. One for each fan.
Here's what they look like painted black and the probes.
And the independent circuit. It takes two of these circuits for my car. One for each fan. A 14in puller mounted over a engine and transmission oil cooler and a 16in pusher. The transmission oil flows constant and the engine oil cooler is also temperature controlled only starting to flow at 180*. I guess Derale thought 180* was hot enough. Just do a search on how water in a cars engine oil evaporates. Its not what most think it is.

Streetstuff

One thing I forgot to mention is that I do not have a heater core right now. My car has extended antique plates so I don't drive it when it's cold anyways, but I will get a heater eventually.

naf

iTrader: (7)

I usually only p*ss off people that work for me. It was not my intent to spread my negative influence any further than its current radius.

Seem a little sensitive? Maybe you went thru SD instead of PI? (1990 0311)

Ron U.S.M.C.

Back in "82" Parris Island, what they consider "old breed" and average of two a year were dying. Then 0351 (Anti-tank/light demolition)That means an educated grunt for those that don't know, at Camp Lejeune .
You and I both have been here for a long time and I don't want to bump heads with a VET soooooo.
Carry On.

mmadden55

Ron you had some useful information that helped, however i gotz a whole different problem.

1986 Firebird 305 has been modded some by PO. Singleelectric Fan. The other day, I discovered that the Fan was not coming on, came across this thread and followed OZ advice. This is where it gets weird.

Pulled the wire off the thermocouple sensor in the block, passenger side by dip stick, switched the key on and low and behold the fan came on, without the wire being grounded. Grounded the wire, the fan stayed on. So it makes no difference now. Key on Fan on. I have found a relay wired into the harness and taped to the wires near the battery. It may be switching the fan on when the key comes on. Or not. Still tracing wires.

The other thing is I have a small blower fan unit over by the battery stuck in the fender well on the passenger side. This is wired to a thermal couple switch in heater hose line at the water pump. One side to ground, the other to the power lead plugged into the relay just mentioned. It works because it switched on the little blower motor. I have no idea what this little motor does, it just blows a small amount of air from inside the fender into the engine compartment by the battery. May have been a battery vent fan or something.

I am thinking of using the thermo couple for this small fan to trigger a relay for the fan. However I have no idea really what temperature it switches at since, the working instruments in the car are the speedometer and the fuel gauge kinda.

Any ideas at this point?

naf

iTrader: (7)

The small blower fan may be the dealer installed fix for the carb 'fuel boiling' issue. I have seen photos but have not run across one in person. It should have a small duct forcing the air towards the carb. As a dealer installed fix, I would expect actual installation to vary from vehicle to vehicle. I would also expect some to be wired to operate only with 'key on' and some to have constant power.

The stock 'fan on' command comes from a ground to the fan relay. The ground was provided by either the fan switch in cylinder head or the 'AC ON' switch within the HVAC dash controls. Verify that the fan relay is not receiving a ground from the HVAC.

mmadden55

May have had the wrong sensor, it had a green wire to it.

^Thanks for the info on the aux fan, it was installed behind the battery inside the passenger fender and was sucking in by the battery and blowing it out above the battery. Looks like there may once have been a hose there going somewhere that is missing. It was definitely switched direct by a thermo couple switch. In any case I removed it since it is not needed, I have an open powerbulge hood on this car so it doesn't normally get that hot under hood.

I have a relay that is wired to something that the aux fan is wired to that had a wire that was getting hot when the radiator fan was on. So I am thinking the fan was shorting to ground which is why it is constant on now.

Any way I am going to use that aux fan as a vent fan on my Astro Van.

Later today I am going to see if I had the wrong sensor out of the block, and if not I am going to rewire my radiator fan, to run off a relay, switch by the sensor that was running the aux fan.

And thanks Ron for good infor on the fan wiring.

Ron U.S.M.C.

Please......... install a 180* thermostat just for kicks and giggles.
If not we will never know
Here I included this .

If that wire was hot you might have to run a heaver gage on the fan power wire.
That's the 30 to 87 wire from the battery terminal to fan and the fan ground wire.

mmadden55

I agree, that is the circuit I am going to use, except I am going to put the thermal switch in the circuit between ign and the relay since it is open, nonconducting, cold and closed conducting hot.

Ron U.S.M.C.

Sounds good. I usually put it on the ignition source ground wire coming off of the 86 pin. Either way will work.
So what switch did you decide to go with ?

rjack37

Did you check the timing?

GeneralDisorder

iTrader: (1)

Hopefully he's checked everything and resolved the problem since this post is 5 years old.

GD