A Cool Running

I'm about to the point of swapping out my direct fit alum 2row radiator for a 65 mustang (17Wx16.5H)with a 2400cfm fan to a 69 mustang 250 alum radiator (24Wx16.5T) with a dual electric fan setup that has 4000+cfm
my end goal is to run a 195* t-stat all year long and never have it run above 205* no matter the outside temp (I want my mechanical guage to never pass the 195* mark again)

I have racked my head around this topic so many times I'm afraid I'll start quoting it...
General Discusion on Heat
I'm afraid I just don't have sufficient enough cooling surface area

I have flushed the whole system countless times, (forwards and backwards) and it's "clean" coming out.
I have been conviced by my cousin to flush one last time try water wetter with 25% coolant, and the rest water, and if it doesn't fix it I'm pulling the plug...
the radiator does AMAZING when it's cool outside, when it's 80* or cooler, but go to 95* outside and it's warming up and don't forget tripple digits, I'm not aloud to run my AC cause I'm running 230*!!! on a 105* day (using a 195 t-stat!)
I don't understand WHY this same size radiator can cool a 400hp v8 but not a measily 115hp i6!!! it's ridiculous!!!

so, anyone out there wanna suggest somthing? I'm really desparate as I'm honestly planning a major remodeling of my radiator support to nip this thing in the butt once and for all

just for kicks and giggles, I'll run my 3 core copper radiator till my new radiator is in... it might cool better than this POS...

8) ok you may have an airflow issue rather than a cooling system issue. have you tried running the car with the hood off? if not give it a try. sometimes air get recirculated around the front of the car and pushed back through the radiator because it is backing up in the engine compartment. sometimes an air dam under the radiator will do the trick. also do you have a fan shroud? one more thing, how many fins per inch is your radiator running? it should be about 16 per inch. if less than that then you will have a lack of surface area, because the radiator was designed for racing and not the street.

rbohm":2m72b2b3 said:

have you tried running the car with the hood off?

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rbohm":2m72b2b3 said:

sometimes an air dam under the radiator will do the trick.

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Rbohm this is ingeneous, I was so excited to try it that I when i read this i dropped everything and took off my hood, went for a drive and it still climbed to 230* I honestly thought this might work...
I honestly feel like i'm getting no where... :deadhorse:

the fin count is 15-16, depending on how you count it...
my 17 inch fan takes up 77% surface area on the radiator

I was just wondering about your AC.
Is there a big condenser in front of the rad?

And advanced timing can increase heat, can it not?
I see your cam is advanced 4°, what's your static timing?

What oil are you running?

Did the 3 row run cool before? Sometimes a radiator can lose the fin bond (an old rad.) or it never had it to begin with and will never cool (as in a poorly manufactured alum. unit i.e. epoxied or poor welding).

8) go back over the basics, what causes an engine to run hot. lean fuel mixture, timing advanced or retarded too far, head gasket leaking, faulty thermostat(yes even new ones fail). does running the heater help cool the engine? when was the last time the block and head were thoroughly flushed? what is your coolant mix?

I'm one of those in the camp that swapping out a good radiator for an 'upgraded' radiator does not solve cooling problems. Sometimes I can overcompensate, but the real problem is still likely there. I can run my 3 row normal radiator (not AL) in 95* days and the needle will barely hit the T-stat set point even sitting in traffic.

Like rbohm said, go back to basics.

Water pump
Condition of hoses (old hoses will collapse when underload, but not at idle)
Timing
Fuel (lean particularly)
T Stat

For how little most of those parts cost, I would suggest replacing them all if they are not relatively new.

Also, is your heater core properly hooked up?

oil = 15-40 been running this for 5 months now, with oil changes every 3k miles

IDK the static timing on the dis... we retared it and it seemed to help, I'll put a timing light to it tonight for a deffinet number, static is to be 12 BTC and 24* mechanical and the vacuum can retards the timing when it sees manifold vacuum, the canister is adjustible. I can try 8* but it don't ping ATM

the condensor imo isn't big compared to other mustangs at the car shows, I'll take a picture and post it, I'd say same size

the 3 row copper ran 'warmer-hot' (according to the stock temp guage, never had it on the new temp guage) until it devoloped a pin hole leak, it's at the rad shop getting fixed for $79, should be done by end of week.

basics
carter YFA - AF mixture was 14.1, we drilled out the main jet to alow almost ~33% more fuel, it's probably rich now @ WOT
autolite 1100v - AF ratio @ WOT is 12.5, I'm going to swap this back on, it's not much power but I know it better and I'll watch the heat
timing- I'm thinking the total timing should be around 38* right? so I ususally set it in the past @ 12* - 14* and a 24* mech advance @ 3k rpm, the vacuum can retards the timing, some how boosts the rpm up when I plug in the can... (i thought the canister was supposed to advance the timing)
the heater is blocked off with a valve as I have a heater AC box in one... no that I have noticed
t-stat- I really don't like the one I have now, I got from napa, I'm going back to orielies and getting another one of thiers. it just seemed more "consistant" the opening was larger too.
block and radiator flushed 3 weeks ago runnign 2gallons coolant and 1 gallon distiled water, and what ever hose/tap water was still on the block
I'll be reflushing the block again tuesday and again when I get the other radiator back

CobraSix, I'm also in the same camp, I'd rather not but if it "solves" the problem, it solves the problem... one thing to think about is the humidiy factor, ur 95* with 30%+ humidity helps the engine... I'm lucky to see 3% here, and in 95* weather it's "okay" and can keep up, it does rise to 195-210 and I'm comfortable with that. the problem is that it keeps rising to 230-250 on the guage in 100+ weather, and my infared hand held confirms the block temp, the rear block/head is close to 235+ and the frontblock is 199ish and the front head is 220*, it shows less water flow might be in the back, but with the front block being 199, I think the block might be absorbing the head heat in the front. I'll drive around with the heater core running and do the same tests again now that it's hotter outside, but I honestly don't think I'll find a difference.

I can put my mech fan back on, and test the cooling capacity CFM, but it won't help in my stop-n-go traffic, I see cooler temps in slower traffic with the electric...

the hoses are new, maybe 3 months, can replace I'll get a new t-stat also,

the water pump IMO is good, my previous one (from summit) "sweeped" out the little hole on the pump and the current (napa) one does the exact same. maybe swapped the water pump 2 months ago. I want to go back to the summit pump

running with the heater core flowing, (windows down) I ran less than 210 in traffic, then hit the freeway and hit 220, the engine seemed more stable but I didn't

same road test- hood on heater core free flow not heater fan,
got on the freeway turned around after a few miles and got off at the same location as before, temps were as follows,
top rad= 223
bottom rad =202 (it ranged in spots along the bottom of 195-210!)
block front = 218
block back = 214
head back = 222
head front = 229
T-stat housing = 225
lower rad hose 189-218?

if I'm seeing this right the radiator only cools up to 30*, granted with hot air, but it should be more than that no? and i'm not running the AC which would make these temps worse...

EDIT: hmm i found something that might be a culprit
my vac can unplugged didn't change the timing or idle, maybe i need to adjust it.
the timing was set to 14*, i retarded it to ~7* will retry the test run.
these temps won't be safe for me to use the AC, it should stay at the t-stat temp and only flucuate with the AC on as the compressor kicks on and off.

It's not boiling over, and it's running OK right?
Those temps are probably not to be unexpected considering you live in AZ.

mp mustang, if you want to rid yourself of overheating, buy the summit sum4917 flex fan, I tried the most expensive electric fan set ups and they did not compete with this fan and a good adapter that puts your fan about an inch from your radiator, I have been burned twice now with this electric fan stuff, once on the bronco and the other on my hod rod chevy truck, no electric fan can compete with drawing air thru your radiator and over your engine and getting it out of the engine bay like a mechanical fan period. Yes you may loose a little horse power, noticeable maybe, I doubt it, it made a 25 deree difference on my blown bronco and now that I put my shroud and clutch fan back on my chevy, absolutely no issues, even when pulling 8 tons, there are engineered applications for electric fans, but not on this application in my opinion, if you do this and still overheat I will pay for the fan and adapter, just PM me. If you choose to go this route, put a paper towel in front of your grill and then after with the mechanical fan and tell me which pulls the paper towel to the grill with the most force.

Jackfish, I want AC with those temps, but that was with the heater core flowing, I can't flow the core and run the AC, i'd just get hot air as they are the same box.
and just by-pasing the heater core with the hoses only seems to be patching the problem, All i want is max hp and mpg (usually electric fan setup) and AC here in the heat.

Broncitis- I appreciate the offer, but i ain't putting a flex fan on here... last one i had took a bite out of the radiator, put a hole in my hood, and destroyed my battery, no sir ain't going to happen again. i still have my rigid 6 blade 16inch i can run, but it's just not the road I want to take with this car.

i'll do my flushings and get back to this topic.

timing- I'm thinking the total timing should be around 38* right? so I ususally set it in the past @ 12* - 14* and a 24* mech advance @ 3k rpm, the vacuum can retards the timing, some how boosts the rpm up when I plug in the can... (i thought the canister was supposed to advance the timing)

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Right the normal at cruse is for the vac. advance to add more timing. Tune to what the engine likes 45-50- some even 60 total Timig. Something seems odd there, dose the advance can still hold a vacuum?

8) one more thing to check is the radiator cap. make sure it holds pressure like it should, and make sure the vacuum break is operating properly also.

Hi MPGMustang.I did`nt notice how much if any you have bored your block.But something that I have noticed over the years is that if the cylinder walls are TOO thin,overheating can and will occur.Just a thought.
Good luck.Have fun.Be safe.
Leo

MPGmustang":34344ckv said:

the water pump IMO is good, my previous one (from summit) "sweeped" out the little hole on the pump and the current (napa) one does the exact same. maybe swapped the water pump 2 months ago. I want to go back to the summit pump

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rbohm":34344ckv said:

8) one more thing to check is the radiator cap. make sure it holds pressure like it should, and make sure the vacuum break is operating properly also.

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Hey Richard, something to go along with rbohm's comment. If the new pump is leaking a bit out the "weep" hole, that would concern me. It would seem to suggest that the cap is not releasing pressure properly (is faulty) or is rated too high.
EDIT: [or water pump seal is faulty]
Do you have an overflow tank? They can aid in monitoring fluid loss, and mainly ensure the system is always full (purged of all air...drilling a small hole in the thermostat can also help with this). I like Stant products for cap & t-stat but can be harder to find these days.

I used this dorman one, compact but good capacity, listed as universal but is rated for coolant and cheap
http://www.summitracing.com/parts/RNB-603-001
even cheaper at rockauto
http://www.rockauto.com/catalog/raframe ... 001-422177

Cap should be only point to vent pressure or liquid...if weeping at WP could indicate system not holding proper pressure, and water boils at higher temps under pressure or does not boil over at highher temps when pressure is properly regulated.
Good luck!

Do you know anyone that still smokes?

If not by a small cigar, get it lit and start the engine with the hood closed. At idle blow a stream of smoke at the front of the radiator. It should flow through into the engine compartment. Then have an assistant increase the RPM to cruse values and blow some more smoke. This should also be drawn into the engine compartment.

Confirm that the fan setup you're running is not creating positive pressure.

Good luck, Ric.

Did the flush tuesday night, replaced the t-stat using 0'riely's 195, I just like theirs better than napa's.
also took the WP off and cleaned up all the rtv to try and re-seal it, reason being I had some RTV floaters a while back and I wanted to make sure I didn't have any within reach I can pull out. but it all seemed clean. I checked the water passages up front (two 1/4 inch holes alowing water to circulate in the front of the head) and found they were clean. I didn't use the same coolant mixture as I'm used to, this time my cousin wanted to see a "what if" i use water wetter... so 2 bottles of water wetter, 1 gal of coolant and the rest of distiled water (about 2 gal).

temps, well I am able to run the AC to and from work. and it feels great, I get up to 210* most of the time, now this is only 8-9 miles of travel, and I time lights with the speedo so I make most greens, until i hit about .5 mile of construction. one day, with AC on full blast, I went home for lunch, and headed back, I turned on the AC to full blast. I saw 210 on the guage most of the way, it crept up to 215ish but when I hit the stop-n-go construction, it was 230* I turned the ac on low and but didn't help, it was already hot. turned it off, and still didn't help, if i did have a mech fan I could have rev'd the heat away. I still don't want a mech fan...

IMO the current system is "good enough" for the autolie 1100v that gives only 95hp and with the timing down to 7* I just got 14mpg... but I can't be certain as I did have the carter YFA on for part of the tank.
the WP is good, I don't loose any water per say (that I can see), maybe only when it was new it would until it plugged itself.
the smoke trick I could do, but didn't the "remove the hood" trick also give a change of pressure in the engine compartment? as I got the same temps w/ or w/o the hood.
yes the cap holds great and I do have an overflow can, I see it always has water in there, never dry and hot and cold has different levels sometimes, depends how far I go.

cooling system never has blown steam, but I don't want it to, I'm more of a "I don't like it doing(not doing) this so lets fix it so it doesn't(does)" and I want the engine to run a constant temp no matter what speed I'm going and no matter what the temp it outside. I'm comfortable in the 210 range as i see the guage doesn't move, I get squirmish around 220-230+ ranges and I'll pull over when it hits 250* as that's just too hot. and I also want to run the AC when I'm hot.

ATM I'm running my 95hp carb, what would happen when I run a 127hp carb? I would create more heat... faster (I have a very heavy foot and often can't lift it off the pedal )
a bigger radiator can cool the water more efficiently... the 24inch wide rad would have a 41% increase in survace area, and give me the option to run a dual fan setup that reaches +4000 combined cfm.

IMO the timing is a band-ade to heat, I'd like to run it without chaning timing as timing is MPG. routing hoses around to alow free flow is also a band-ade, as I would have to switch them back to use my heater. Jet's I understand, I should change them to run a healthy engine during the summer or winter months as an ECU would control the amount of gas too.

I finally have all the parts to mount Mikes holley 350 on for a road test, with a bolt on 32hp I'll watch the temp guage, with more HP i suspect more heat, if it climbs too quickly I'll go for the bigger rad&fan setup.

Bear in mind that if your guage is using a sensor that is located on the back of the head, that is probably one of the hottest areas, and your temp readings may be influenced by cylinder head temperature.

I have a guage sensor located in the old PVS hole on the temperature thermostat.
I believe it gives a more accurate reading on the actual temperature of the coolant, and on my car it hits 180 and stays there pretty rock solid. But I don't get the air temps up here that you do.

Jackfish brings up a good point about the temp transducer. You mention that you don't boil over. It looks like you confirmed the temps with another gauge. I had replaced the temp transducer on my Stang with a new one and the the temp readings were not accurate, even though the stock gauges don't have actual temp readings. But I ended up replacing it with an original transducer and it was reading in span again.

With regards to removing the hood: Years ago I had replaced the hood on my Vette. I putted around town without the hood on the car while I was painting it. I was surprised that I had an instant cooling problem with the hood removed. I figured cooling would improve. But without the hood, air does not want to enter the radiator. While driving, the air will enter the engine compartment from above and build up pressure in the compartment. This decreases the pressure differential across the radiator and less air moves in through the fins. As you drive with the hood in place the air passing under the car creates a lower pressure in the engine compartment. So the hood helps the cooling. This is also true if you have a radiator has any seals around the edges of it to help air from flowing around the sides of the radiator. These seals are important on Vettes, because they typically have smaller opennings for air than many cars.

I know your cooling problems have been going on for years, but how sure are you that the timing is correct. Was the balancer replaced? Has the timing mark slipped? You mentioned the timing did not change with the removal of the vac hose. Does the vac can hold vacuum? When you apply vacuum to it at higher engine rpm, does it change? You mentioned that you were thinking of retarding the timing from 14 to 7. That will likely raise the engine temp. To help the cooling, you need to dial in all the ignition advance that you can as long as you don't ping. You might want to run manifold vac to the distributor unless you have the load-a-matic and spark control valve setup. The additional timing will increase the idle speed and help cooling. It also helps the engine cope with the load that the AC will put on it. With all new cooling equipment, I think you have a timing problem.
Doug