Heat, heat and more heat!!

[DocDirk]

Well I thought since my BB Ford wouild overheat with the hood on and wouldn't overheat as long as I had the hood off, that the 1950cfm fan plus the hindered engine compartment airflow was my main cooling problem. I purchased a 3000+ cfm fan and have yet to install it. It's been a nice balmy 65-70 degrees here lately but we're having a bit of a heat wave today and I drove in 95+ degree April weather (phew!) and that nice steady 185 degree temp reading moved itself to 225 again. No other changes in the car were made, just driving in 30+ degrees warmer weather. I ran it up onto the freeway in the hopes that the ram air effect would reduce the temp but it didn't. I'm wondering....

Does anyone know at about what speed the ram air effect exceeds the cooling benefits of a good strong fan? If 55 mph exceeds the fan's capacity to move air through the radiator with an good shroud then the fan alone won't keep my car cooled in stop and go traffic on a 100 degree summer day around here I've read every post on the engine heat/cooling topic on this wonderful forum and have made every effort to optimize the system other than not yet rerouting the surge tank hose from the pressurized radiator side to the water pump intake hose as suggested by Kitcarbp.

I'm beginning to wonder if this is really a Northern Canadian car in disguise??

Thanks!

Dirk

[FWB]

dirk i've been talking to bill and i am privy to his idea, but before that road is taken , is the area around the radiator blocked so the air moves only thru the radiator? what is your total advance set at? are there any vacuum leaks, i mean verify this with a vacuum guage. is your radiator hose collapsing? is the water pump actually moving water. now don't take offence but is the thermostat in backwards? what is the motor i know 460 but what is the build?
email me my address is in my profile

Fred

[Tom Wells]

Dirk,

Don't know how far you've chased the trapped air but this turned out to be my major problem. Once cured, my car runs cool regardless of speed.

Burping the cooling system is vital and frustrating. I have to cycle mine at least five times (cold to warm to cold) and between, remove the cap and squeeze the hoses to get the air out. Then cycle again. When I can no longer observe any air bubbles when I squeeze, it's done.

Through all of this, the overflow reservoir needs to be kept nearly full so when the car heats up the water goes into the overflow, then returns to the radiator without sucking in any air from a nearly empty reservoir.

As a second thought, there's a thin metal plate that goes behind the 460's water pump along with a second gasket. If this plate is omitted, overheating will result.

Hope this helps,

Tom

[vector1]

imo

usually 40mph+ should be driveable without fan running.

your cooling fins are not plugged, you can see clearly through the cooling tubes?

using a shroud on your cooling fan?

radiator ducted to front opening?

air as much as possible removed from cooling system?

bypass hose used or holes drilled in thermostat?

air moving through the radiator must have someplace to escape to, preferably lower pressure area, such as wheel wells. is your engine bay sealed off from the wheel wells keeping the air from moving freely through the radiator? especially if you have a hood scoop and are pressurizing the engine bay.

overflow hose routed to bottom of overflow tank so when coolant is evacuated it will be recovered?

thermostat in good working order?

just some things to think about. hth

[DocDirk]

Originally Posted by FWB

dirk i've been talking to bill and i am privy to his idea, but before that road is taken , is the area around the radiator blocked so the air moves only thru the radiator? what is your total advance set at? are there any vacuum leaks, i mean verify this with a vacuum guage. is your radiator hose collapsing? is the water pump actually moving water. now don't take offence but is the thermostat in backwards? what is the motor i know 460 but what is the build?
email me my address is in my profile

Fred

Fred, no the front of the radiator is not shrouded. The advance total is 32 deg at 3000RPM. My radiator hoses are Coolflex, no collapse there. The water pump does move water, tested for output, actually overdriven and rated originally at 20% above stock. Thermostat is in correctly thanks The build is 533 BB Ford with a Vic. Jr. intake, Trickflow heads, ported, cam specs have been lost but are on their way to me from the mfgr as we speak. The exhaust baffles are too small at 1 7/8 but I'll soon have those replaced by 2.5" ID baffles. The engine was running rich at the BAR testing done to qualify the vehicle for smog in December. I thought the small baffles might cause it to run lean... Dyno tune is coming but not until I have improved air filtering surface area and less restrictive muffler baffles.... mix is 70/30 water/antifreeze, thermostat 180 deg. puller 1950 fan with very good shroud.

Thanks,

Dirk

[DocDirk]

Originally Posted by vector1

imo

usually 40mph+ should be driveable without fan running.

your cooling fins are not plugged, you can see clearly through the cooling tubes?

using a shroud on your cooling fan?

radiator ducted to front opening?

air as much as possible removed from cooling system?

bypass hose used or holes drilled in thermostat?

air moving through the radiator must have someplace to escape to, preferably lower pressure area, such as wheel wells. is your engine bay sealed off from the wheel wells keeping the air from moving freely through the radiator? especially if you have a hood scoop and are pressurizing the engine bay.

overflow hose routed to bottom of overflow tank so when coolant is evacuated it will be recovered?

thermostat in good working order?

just some things to think about. hth

Thermostat is in good working order (pro quality 3 months old)

Overflow hose is routed to bottom of an overflow tank. Come to think of it I haven't been making sure the overflow tank has fluid in it before a drive. I will from now on.

I have a very large hood scoop but don't expect it to help me much with ventilating the engine compartment. Wheel wells are open for airflow. The engine compartment has been criticized by others on this forum as poorly designed for exit air flow.

I have burped the cooling system as much as I can and refilled it until it won't take any more...

Tom - my Coolflex hoses won't allow me to burp the system by compression...maybe I should find a hill and park it facing uphill?....

The radiator is not shrouded to the front opening, I wasn't sure that would make a lot of difference, does it?

Tom - Yes, the plate is there behind the water pump...checked that after you responded to another post with that information, thank you

I have not drilled holes into my thermostat.... should I?

Signed......frustrated in Krazyfornica

Thanks!

Dirk

[vector1]

drilled thermostat won't help the cooling, just helps keep temperature spikes down and allows the bleeding process to go smoother imo.

hood scoop will not ventilate the engine compartment, that is my point. why is the engine compartment criticized for poor air flow if the wheel wells are open, something else restricting movement?

overdriven water pump? wouldn't be cavitating would it? is this normal setup?

[Steve Gallegos]

Dirk, one thing that might be happening is that your water pump is too good, I tried a new 3200 cfm fan and it did not change a thing, my temp still ran at 220. The pump is pulling the water through the radiator so fast that it doesn't have time to cool. That's what happened to me. I took out my thermostat and replaced it with a restrictor washer, I used the medium ring. Temp now runs between 180 and 190 even in 100+ heat. I have a Backdraft, I got the part from Reg at Backdraft. If you go to the Knotts cobra meet this Saturday 4-25, go to the Backdraft display and talk to Reg, I'll be there Saturday after 9AM also, or you can find him at www.backdraftracing.com Good luck Steve

[DocDirk]

Steve, I don't know, you might be onto something there.... My water pump was rated at 20% over stock output by the engine builder who installed it. I also have a March pulley on it which is smaller than the crank pulley, meaning it's overdriven and puts out even more water (WPM? LOL)

I have nothing to lose, I'll search for the part - what might it be known as? Water flow restrictor? Thermostat replacement restrictor washer?

Does anyone know how important shrouding the front of the radiator is?

Dirk

[Rick Parker]

Moroso makes them, 3 in a kit different hole sizes.

[Jac Mac]

If the car runs cool with bonnet off , but not with it on isnt the problem in airflow under the bonnet, you say you have a large hood scoop, is this sealed to the carbs only so it doesnt creat pressure under the hood & therefore prevent air from coming thru radiator when car is moving. Venting around wheel arches is easy to check, tape some tufts of wool & see if air is coming from that area while moving. Rule of thumb is lots more outlet area from underbonnet than going in & these should be in low pressure areas. Big motor like 460 is a real problem to get air circulation past.

[Steve Gallegos]

Dirk, when you get the restrictor, start with the middle one. Try this first before you buy a fan. I diid't I went with the fan first and it cost me $300.00 for the fan, plus install. The washer is cheeper by about $295.00. Steve

[1blackbb66]

Dirk,

You shouldn't be concerned about 225* I have an iron head 460 in my West Coast. I run a 190* T-stat and twin 900 CFM pusher fans on a T-stat. I have the fans set to come on at 240* and as soon as they come on, which is only in traffic, the temp comes down to 210*-220*. The fans never run when I'm moving faster than 30MPH. Cruising on the freeway on a 75* day she will run about 200* to 220* depending on how hard I'm running. You must remember that a 50/50 mix of antifreeze and water with a 15 lb cap will raise the boiling point to 265*, and a 70/30 mix, which is what I run, won't boil till 276*. These numbers come right off the Prestone jug. I have always run all of my engines hot. They make more power, run cleaner and last longer than running them too cool.
I'm sure there will be many that strongly disagree with me on this, including some engine builders, but I have over 35 years and many engine tear downs that prove to me it's good to run them hot.
If you want some interesting reading, do a search for "Smokey Yunick Adiabatic Engine"

Ray

[kitcarbp]

Dirk, If you are overheatig when above 35 mph its either a water flow issue (not enough) or as FWB pointed out there is not enough air going through the core, (its going around it) shroud in front of rad to improve.
Do not put a restrictor in place of the thermostat, you want to maximize water flow not slow it down, this will make it worse. Putting the larger elec. fan in will only solve problems of low speed overheating when you dont have enough air velocity over fins and need to pull the air through core using high cfm fan . There is still something mech. not correct. (you said WATER FLOW IS ok). I dont think you are cavitating pump at highway speeds (2-3K rpm), this would happen at higher engine/pump rpms.

Initial timing checked with a timing light is confirmed to be what ? (between 10-16 BTDC is the range but depends on your combo and octane)

Engine builder should have shared exactly what INT timing should be on pump gas not race gas. I assume he set up engine timing for intended pump gas (92/93 octane yes ? Retarded ign timing will add heat to combustion. Too lean of a A/F ratio at steady state cruise is another root cause of over heating at speed.

Engine builder should confirm your carb was set up and A/F ratio checked while on dyno at steady state. Based on what you have now described, the 3,000 cfm fan will not solve this issue of overheating while cruising.

[Garage10]

Hey Dirk
I have my rad out to do that surge tank hose mod and am waiting for a higher cfm fan. Now I really didn't want to do this but maybe I will put it all back together and try it with just the hose mods to see what the results are. Bill and I really think coolant is really just circulating through surge tank and not fully through rad. My new set-up will eliminate that chance. Will let you know results but not for 4-7 days as I'm busy this week at work.

[DocDirk]

Bill and Brent, I still haven't installed the fan. I have ordered but not installed the flow restrictors ($6). Picturing the water flow plan I don't understand why there has to be the larger line from the radiator to the surge tank after all..... isn't the other end of the radiator already plumbed to the surge tank? Why not just eliminate that larger line altogether? The surge tank vents to an overflow tank anyhow... what function does that larger line serve? I've half a mind to just plug it at both ends and see what happens.... but then I've only got a half a mind when it comes to automotive engineering, that's prolly what got me into this spot in the first place

Truckin' along!

P.S. is it true that 220 is an okay operating temperature???

Dirk

[Garage10]

I can't say for sure but have read all over here that 210 is about as high as you want to run. Has to do with aluminum heads not liking real high temps and warping causing head gasket failure.

[Tom Wells]

Dirk,

my Coolflex hoses won't allow me to burp the system by compression

I'm still stuck on this

Maybe someone could suggest an alternate method for burping?

Perhaps something like this: http://www.ehow.com/how_7369_burp-cars-cooling.html

Also,

Be sure to move the heater control to the full, open position. It's part of the engine cooling system, and may have air trapped in it.

If you think this is a rare problem, I used these words in Google -> burping cooling system radiator <- and got over 6,000 hits...

Bottom line: other mods may indeed help; just make sure this step is successful before making any of the other changes!

Regards,

Tom

[kitcarbp]

Dirk, The Surge tank large diameter (5/8) line on the WC is referred to as the FILL line and gives you a convienient place to be able to fill the coolant system when radiator is mounted below the height of the engine. The surge tank needs to be the highest part of the cooling system to collect and purge trapped air into the coolant recovery reservoir. Trouble is the surge tank is a little lower than therm. housing. Our WCC and most systems are an "outlet temp controlled system" (thermostat is on the engine outlet upper hose) and the fill line needs to feed into the low pressure side of the cooling system. For the 460 in the WC, this means you have three choices for plumbing.
1) Feed fill line into top of rad outlet tank (low pressure side of rad)
2) "T" into the lower rad hose. (what I did because it was easy)
3) "T" into the by-pass pipe between water pump and intake manifold. (WIZARD did this on his WCC)

Read the section under RADIATOR CAP LOCATION at this link for surge tank info.when using a cross-flow rad mounted lower than the engine.
http://www.stewartcomponents.com/tec...ech_Tips_2.htm

With that said, burping this system is a PITA. Therm. housing as a threaded port to aid burping at fill-up and thermostat should also have by-pass holes (I drilled my own) to allow any remaining trapped air to exit the engine and enter the radiator while running to facilitate air from exiting the engine. You can also loosen water temp sensor in the intake during re-fill to burp engine. The rad low pressure side (outlet tank) has the air bleed line connected to the very top of outlet tank on the rad back into the top of the surge tank (also called de-gas line). Flow restrictors are not needed and will inhibit cooling in a street application, thermostat only! see this link http://www.stewartcomponents.com/tec...ech_Tips_3.htm

[Garage10]

I just picked up a GM air bleeder. It has 1/8NPT and it goes on your intake or your thermostat housing and has a small wheel on top to open and bleed system. I will post part number if anyone wants. Hopefully this will make it easier and not so messy to bleed. Still waiting on fan.
Take Care
Brent