not happy with coolant system :(

I'm not the expert on this but spent a lot of time on this as well.  I'm using the Ron Davis radiator that lays forward but both fans are suckers on the inner side of the radiator.  I have the header tank setup as well and I know that you have to have the coolant level above the lower tank hose but not completely full so that the air has somewhere to go.

Did the coolant actually boil over after you parked it?  I've been spooked by high temp readings but as I've learned on this forum, if it isn't boiling over then it isn't an issue.

For reference my new Ford Raptor will clip 230F on the freeway if I'm driving 80MPH or more for extended periods of time.  It doesn't overheat but the gauge gives me the heads up reading.  It has front mounted fans and I suspect they may be stalling out at high speeds due to high pressure.

I'm sure some of the experts will chime in here shortly.

John

#2551

I might be premature in my conclusions.   I am thinking I did not comprehend the tempurture rise to fully open an 180F  thermostat (and when to cut off the fans.).   I have the fans cutting off when the radiator outlet is 160F, think 20F drop from 180F inlet. while it looks like with 20F rise to fully open thermostat,that would be the seen 200F.   so I proably should change the fan switch and consider 200F the operating temp

I just ordered a Tim Myars 160F thermotat and that might be the route I try

But...back to basic.

75F day

180F thermostat (say 100% open at 200F)

both fans running

the fact the coolant goes to 200F (and climbing) indicates insufficient cooling ... period!

Might be a dumb question, but are the fans rotating the right direction?  If the wires are reversed maybe the motors are running backwards......just a thought.   (I've seen it happen).    I have muti blade Meriah fans, 5 core copper rad in the stock position, fans are still pusher and I also have a 3rd fan (sucker) on a toggle switch in  case of heavy traffic (never had to turn it on), overdrive pulley, 180 thermostat, Hi flow water pump (but not excessive as too fast a flow sometimes pushes the coolant through too fast and doesn't give it a proper chance to cool), and no overheating problems.  (although I did have an overheating problem when the engine was rebuilt as one head gasket was reversed blocking the coolant from flowing through the head, which is possible on a Cleveland).  (Another time the top rad hose inner lining collapsed blocking all circulation and you couldn't even tell from the outside.  Found it by accident when taking things apart.....)

Just a few quick thoughts.

I would not use a 160 degree thermostat. It wont help and may allow the engine oil to run to cool in cold weather that contributes to added wear and compromised power output.

Your temps are actually very good. We want oil temps between 210 and 220 degrees.

Your highway temps are very good. That temps rise during slower driving is evidence of reduce air flow through the radiator. (no surprise)  Thus, increasing airflow with higher CFM fans would lower temps. However, if your temps are below 220, I wouldn't change a thing. Assuming you are running a 16lb cap, water boils at 265degrees with 35% ethylene glycol; 253 at 12lbs. Lots of margin.

Some info at https://www.spacecitypanteras....Cooling-JTaphorn.pdf

JT

what is making me cautious as temps get to what is "normal" ie say 210F.

I am running a 7psig cap (~230 boiling).

long story... BECAUSE, I wanted the Gates heat shrink "clamps".   during my first mile after car came from shop, a bottom hose blew off (dumping all coolant).   the Techs that deliveried did a change out of with band clamps underneath and removed gasket from 15psig cap.   Plans were to return car to shop to replace other Gates heat shrink, but I keep car for more testing.

I am thinking the remaining Gates heat shrink have seen more than heat to set up and I should try a 15 psig cap with local drives and see if they hold.   I need to run that by shop because if one blows, they are to send roll back (4 hours away).  the restro shop is providing "warrenty"

IF i accept 200F as normal running, I'll need to change fan switch to cut off higher.   durring interstate drive today, fans stayed on at speed.

I have verifies fan rotations.   hot air blowing from both sides, behind radiator

STILL . . . I would expect idling to stayed below 200F on a 75F day

Just throwing this in the ring. Had the same problem but my guy put a vacuum on the cooling system and sucked all the air (pockets) out of the system since there are lows and highs in it. People here would know better

@DaveT posted:

Just throwing this in the ring. Had the same problem but my guy put a vacuum on the cooling system and sucked all the air (pockets) out of the system since there are lows and highs in it. People here would know better

do you have the "self venting" modification?   I was thinking that midigated the need to pull vacumm.   But, I'll see if I can find some one with rig and give that a try anyway.

You may have already done this but if not, I would try measure the temps with an Infrared thermometer if you can.  The gauges are not always accurate and may be off be giving higher readings.

John

I suffered with borderline overheating for 12 years and after doing everything I could, Hall 45 degree radiator, Flowcooler pump, more fans, smaller pump pully. Someone else finally figured that the orifice plate hole was one size larger than the RS thermostate plug. I matched that up and all my problems went away!

I actually took that plug out, soldered a penny over the hole and put a regular thermostat in it. My car was a former track car and didn't have a thermostat in it when I purchased it. (amongst a lot of other things) but its fast

Overheating at low speeds indicates a fan issue. I'm with Steve M. here. Your fans are probably blowing away from the rad, as opposed to towards it. Are you sure they are "pushers" and not "pullers", that are designed to mount on the rear of the rad? Which vendor did you buy the fans and rad from and why are they not helping you? 

Comments to your setup - take them for what they are based on what I found works for my car:

1.  180 degree thermostat - correct.  160 will not help in any way.  Will make worse.  Been there, done that.

2.  7 lb rad cap -  why ?- should be 16 lbs.  A higher pressure cap HELPS prevent overheating.

3.  Converted overflow to pressure tank - why?  I don't follow how that helps in the cooling system working better and to me seems to further foul correct operation and make something simple very complex.

4.  Hard line from top of rad to tank "self bleeding" - if system is vacuum bled properly, not needed.  Just another line to leak and source of an air pocket.

5.  Gauge temps could be off for many reasons - agree with other comments - if you want to know real temps, get an IR thermometer.

6.  Overdrive pulley - IMHO - not needed - another vendor's wet dream.

7.  Fans blowing from front - fine.  (They are spinning the right way right?).  They are wired off the battery and getting plenty of voltage and putting out probably 3000 CFM?    200 as set point??  I have mine on a manual switch.  On for slow driving and off when I hit the highway - keep it simple.

8.  As several old timers have said to me over the years "So your car is overheating?  its it puking out the cap?  If it isn't , then it isnt overheating".  So is yours puking coolant at the cap?

9.  Why does car appear hot after driving it - heat sink from hot motor and coolant being very hot and NO air moving through the radiator when stationary.  Mine will  be at 210 if I drive it a while and then pull into the garage and let it sit and idle (which I don't).  

I think keep it simple on these cars and the cooling system.  

@panterapatt posted:

Comments to your setup - ..

why ?-

to further foul correct operation and make something simple very complex.

I think keep it simple on these cars and the cooling system.  

Oh well.   things were done .

just going to record what I did today.

got a 13 cap to replace 7

jack front up (cleared tires)

filled the pressure tank to top, cold

idling under shed, slight breeze blowing through. cool.

with in a few minutes coolant came up to 180, during this ramp up, the 13 cap relief peed coolant.

using a contact probe, the swirl tank was about 5 lower than Sniper coolant (sender front of block)

the fans came on when radiator outlet temp reached 150F

over the 30, 40 minutes idling, fans running, the coolant creep up to 200F with the radiator outlet slightly under 170f.   (another problem that over shadows my concern of coolant system is the alternator is insufficent to run fans, thus draining battery durring run, even crusing)

after shutting down, there was no gurgling nor  puke.

the amount peed was 20 ounces (40 in^3).   that coolant was cloudy brown, not clear green

after cool down, pressure tank level down about 4"  (about 40 in^3)

the other (main) reason for idling was to test the gates heat shrink "clamps" with increased pressure before risking a leak on a drive.  (the reason for the 7 cap)

The cloudy brown coolant comment sounds like you probably need to the flush the system.

It's easy to check the fans to make sure they are blowing into the radiator and not away from it.   Just put you hand behind the radiator and feel for air being pushed thru.  It could be something simple with the fans being wired backward.  They will run whether the wiring is correct or not.

Since you are trying to check all your gates connections, I would kill two birds with one stone here.

I would flush the system first and then use a vacuum pump to fill the system.  This is super easy and gives you the time to find leaks without the car being hot and also pulls all the air out of the system.  I used this system from Harbor Freight and worked well.  Cooling System Test and Refill Kit (harborfreight.com)

John

#2551

Another thing to check: on the fan shroud, there should be an arrow somewhere, that indicates the designed direction of airflow. Make sure that arrow is pointing towards the rad, not away from it. The arrow might be cast into a fan blade or the motor housing itself, but it's likely there somewhere.

I assume you're using the electronic temp reading from your EFI system, not the known-inaccurate stock water gauge. Where is its temp sender? It should be in the block under the thermostat to match where the stock sender was in millions of Mustangs, Fairlanes and Galaxies. High indicated running temp was one of the earliest 'problems' Ford encountered (1972!), and they used several no-cost-to-Ford fixes. They are all listed in the Ford TSBs (Tech Service Bulletins), of which you should have a copy.

One was putting the stock gauge sender in the small water reservoir to drop the indicated temp by 10-15 F. Another was to install a resistor in the gauge line to do the same thing- often combined with the odd sender location. And there were two different resistors recommended- a 5 watt and later a 10 watt!

Note there were also two stock gauges- a 0-220F and a later 0-250F. They read differently on the same engine. Normal 351-C running temp is 210-225F with excursions higher under heavy load. The early gauge will be pegged which scared owners so Ford went to the later gauge in mid-1973. As mentioned, my late model Z-28 normally runs 230F; 'Hot' is 250F!

the Sniper EFI sender is located in the engine block and display is digital.

while idling, about 190 displayed, contact on swirl with fluke Ktc contact was ~187 so I think Sniper is near accurate.

the Veglia is the 220 with sender in the water pump inlet, don't know brand sender.   with Sniper 190, Veglia indicates ~170.   the fluke contact on upper radiator 160.  so about true

I also have a 250 idiot light switch in swirl.   this mimics the systems i was familiar with at work where the inlet was control / monitored with an alarm when outlet exceeded design rise.

Both fans are off switch in upper radiator, suppose to be rated cut off 160, but observed it came on at 150.

NOW. . . My current conclusion is ;  Since I've had car weather has been cold 30 - 50.   short trips at 55 mph had the Sniper display 185.

the day of this post, weather was 80 and I made first substained 70mph drive.   my attention was focused on the fact the fans remained on while at speed with Sniper indicating 195 to 200.   AND given the alternator is known to be undersized, I was concerned about battery during 2 hour driving.   PLUS, part of the quick fix when the Gates heat shrink blow off was use 7 psi cap (boil point about 230) I worried I might get stuck in traffic going back home.

another biggie is I get overwhelmed quickly lately.   So I am thinking I have unrealistic expectations that 180 thermostat would keep coolant at 180.   not considering reality 200 is proably expected at full load.  with radiator outlet temp about 170

the significant change I have currently made is installing 13 cap (~ 250 boiling).   The next items that are needed are;

1) replace alternator

2) raise the fan cut off temp.

Yesterday, weather 50, I took 4 hour drive 65 / 70 mph and fans only came on in stop n go traffic.

the shop has wanted to take the car back and make those fixes, BUT I have been driving and not making arrangements for them to do so.  Maybe in the next week or so.   then I will revisit my statisfaction.

fans off vs fans on

Before you do anything else, get rid of those Gates heat shrink hose clamps. Replace them with high quality, stainless steel hose clamps. Someone previously suggested you get a vacuum coolant filler. Get one and make sure your cooling system has no leaks. This would be after you’ve replaced the clamps but before you fill it with coolant. When you pull a vacuum in the system, it should hold for “hours”, without any loss of vacuum.
Why are you using 160° fan switches? With a 180° thermostat, 185° or 190° would be more appropriate. It’s useless having your fans turn on before coolant is even circulating through the radiator or at highway speeds. Can your Sniper EFI system control the fans? If so, that might be better.
Did you confirm that your fans are blowing through the rad?
At 190° or 200° your system isn’t close to overheating but you have some issues you need to deal with before your cooling system is correct and reliable.

When I was evaluating cooling fans and shrouds, I found that how the fans are wired makes a large difference. If you plug any fans into the stock wiring, they run.... at some rpm. If you direct-wire them to the battery, with only a relay or on/off switch so they get a full 13.8VDC, many fans will run noticeably faster, and fan air output is not linear. 15% more fan rpm can = 40-50% more cooling air.  Before modifying the wiring, check at the present fan connections to see exactly what voltage is available now. Then hot-wire them and see what happens. You really need an anemometer to check airflow quantity but a piece of stiff paper in the breeze will show trends.

The reason this occurs may be because if you look under the flat bar that the hood hinges bolt to, you'll find a large factory-taped bundle of wiring. Inside are many FEET of extra wire folded into the bundle, some not hooked up. There are many extra connectors also, with a voltage drop at each one. We think the front wiring loom came from some large front engine car and the Pantera is much smaller. By stripping unneeded wires and connectors out of the bundle and re-taping, voltage to the headlights, fans and other up-front devices is improved.

Food for thought- you already know that sucker fans are more efficient at cooling than pusher fans, since a sucker shroud causes cooling air to move thru much more of the radiator core area. While most of us lay the rad' down for convenience, its quite possible to run shrouded sucker fans behind a stand-up radiator, even a larger one than stock. In any case, fans & shrouds are not needed above about 30 mph.

@davidnunn posted:..

Why are you using 160° fan switches? With a 180° thermostat, 185° or 190° would be more appropriate. It’s useless having your fans turn on before coolant is even circulating through the radiator or at highway speeds. Can your Sniper EFI system control the fans? If so, that might be better.
Did you confirm that your fans are blowing through the rad?
At 190° or 200° your system isn’t close to overheating but you have some issues you need to deal with before your cooling system is correct and reliable.

my "reason" for 160.  - the fan switch is to regulate the temparture of coolant leaving the radiator.   I expected a 20f drop across radiator with 180 leaving thermostat.

the Sniper would use the temparture sender at the thermostat.   that location is not regulated by fan operations.

I can't get by with Your philosiphy and Commander Montgomery Scot's - "The more they overthink the plumbing, the easier it is to stop up the drain."  In my former Life, I made my living by trouble shooting overly complicated controled systems, just trying to relive those glory days

I am NOW begining to realize normal should be around 200 (at the block sender).   corrected those other problems should let me get there

@bosswrench posted:

When I was evaluating cooling fans and shrouds, I found that how the fans are wired makes a large difference. If you plug any fans into the stock wiring, they run.... at some rpm. If you direct-wire them to the battery, with only a relay or on/off switch so they get a full 13.8VDC, ..

I am NOT getting full voltage because of undersized alternator.   when fans come on voltage drops from ~14 to 12.1 .   My directions to the shop was more and seperate runs of copper to relays and then to fans.

When I upgraded my condensor fans, I had to upgrade the alternator too. I went with 100 amp.   Believe it or not wires can wear out, As the current runs through it, the electrons eventually build resistance. I had a Corvette with a hot start problem, and when I replaced the wire to the solonoid I noticed it was stiff and actually brittle.  I realize we are talking about radiator fans, but same difference.  BTW< I also pull air in from the rear so as not to suck engine heat and push out through condensor.

Don’t all Pantera’s pull air through the condenser?

@jfb05177 posted:

my "reason" for 160.  - the fan switch is to regulate the temparture of coolant leaving the radiator.   I expected a 20f drop across radiator with 180 leaving thermostat.

the Sniper would use the temparture sender at the thermostat.   that location is not regulated by fan operations.

I can't get by with Your philosiphy and Commander Montgomery Scot's - "The more they overthink the plumbing, the easier it is to stop up the drain."  In my former Life, I made my living by trouble shooting overly complicated controled systems, just trying to relive those glory days

I am NOW begining to realize normal should be around 200 (at the block sender).   corrected those other problems should let me get there

But with a 160° fan switch, your fans would always be “on”. Even if your fans could lower the temp to 160°, you wouldn’t want them to. Ideally, you want your coolant temp to rise to normal operating temperature and stay there. If you replaced your 160° fan switch with a 185° switch, I believe you’d see no change in your operating temperature but your fans would cycle on and off. Most importantly, they’d switch off at speed, when they aren’t needed. The nice thing about having your Sniper ECU control your fans is, you can experiment easily with different trigger points.

Don't all Pantera pull air through the condenser?

No. Thats a stock 'pusher' fan setup. Many have upgraded to sucker fans that pull air thru.

I think David was talking about the air conditioning condenser in the back…

With my rear condensor fans, I tried it both ways and I get colder a/c sucking the cooler air from outside and blowing it into the engine bay.