cooling problems

[funnycar]

I have a 16" electric pulling fan. Alum. 2 core rad., it has a reverse rotation water pump. I have blocked off openings so that all the air goes thru the rad.. It wont recover after it reaches 200 and keeps climbing up to 250. It doesnt cool down going down the highway or in trafic.

 

[funnycar]

I took the heater core out along with the heater. my serpentine belt group is from March and a ford racing rad.

 

[funnycar]

I have a 180 deg.high flow therm. I run a 50/50 mix water and ant. along with a product like water wetter.

 

[funnycar]

I made a mistake , I have a ford racing reverse water pump

 

[savage]

I'm really interested in this looping of heater hose causing over heating problems. I haven't had a heater for years and it 's been looped, with old engine and now with it rebuilt and bored over .60 no over heating problem.

 

[Broncobowsher]

Electric fans and Broncos are not usually a good combination. For an electric to really cool a Bronco it needs to be drawing something in the 40 amp range.

Take the hood off and go for a drive on the highway. If it still runs hot, you have a water flow issue. If it stays cool you have an airflow issue. Probably not about getting air into the radiator, You stated you have that sealed off pretty well. But getting the hot air out of the engine compartment. Cowl induction hoods pump air into the engine compartment, fighting what is coming through the radiator. Close off the cowl induction hood unless it is a sealed ductwork to the carb. What do you have for a lift? What about a front bumper? Lifts tend to leave the front axle hanging out in the breeze. They block a lot of airflow. It isn't just the diameter of the tube, aerodynamic effects reach beyond the hard surfaces. This tends to make air pile up under the engine compartment, pressurizing it (like the cowl hood) and fighting the airflow through the core.

The 351 blocks are a little wider. There is some thought that they block some airflow down the sides of the engine. Vented inner fenders have been around for years for this.

All of this and I hope you have already gone through the engine tune to make sure it isn't too lean at cruise and the timing is set right.

 

[74strokerbronco]

I'm really interested in this looping of heater hose causing over heating problems. I haven't had a heater for years and it 's been looped, with old engine and now with it rebuilt and bored over .60 no over heating problem.

It is not always a issue, if the rest of the cooling system is working well and engine is tuned well . the majority of the flow when the thermostat opens is water from the radiator. Its not a cure all but something to consider when chasing down things that are contributing to a hot running motor and I have seen it- cured it in hot motors. I would wager that a looped hose will make the thermostat open wider and more often and longer then if the loop was pinched off or the fittings capped. I look at it this way, there very easy and cheap to cap(any auto parts store will have the rubber caps for a buck or two or even loop it but kink the hose or pinch it down to restrict the flow) and why would I want to recirculate hot water when if I cap it I know 100% of the water the pump is moving will be cooler water from the radiator and then from there the thermostat can do it's job of regulating. .

I'm running in my EB a near 700hp 408 dart block that has siamesed bores, big heads, timing at 34*,180* therm, idle afr of 14, cruise afr of 13-13.5 and wfo afr of 12-12.5 on carb, and it stays wonderfully cool with a champion 3 core with no shroud and 5 blade flex fan and milodon hi volume aluminum pump all on the factory belt pulley setup. I run it on the street, in town, highway, sand dunes, general wheeling etc. and I run the heater outlet and inlets capped and lower half of inner front fender wells removed and c4 cooled by external cooler and not in the radiator . I live in Oregon we seldom see a 100 degree day but 80's -90's are common in the summer and if there was a sbf combination that should require heavy cooling I would think mine would be one of them.

these are the unmentionable causes for overheating still not discussed , cracked cylinder head or block allowing combustion gases into the coolant, blown head gasket doing the same, engine builder error and head gaskets installed wrong . . not trying to be a downer just pointing them out. .


funnycar have you checked for combustion gases in the coolant or can you see bubbles percolating in the radiator? ? are you sure you need the reverse rotation pump ? have you verified water temps with a lazar temp gun on the intake near the thermostat and top and bottom of the radiator??

 

[savage]

What's interesting, this is the first time I've heard that this may cause overheating, When I did a search about this subject, no one talk about it causing overheating problems, and suggested to loop it, and not block it off, if you had a leaky heater core or you eliminated it.This one article was really interesting about the cooling system, he talks about it in paragraph 5. http://www.fourdoorbronco.com/board/showthread.php?5230-Engine-Cooling-System

 

[74strokerbronco]

http://www.fourdoorbronco.com/board/...Cooling-System

he only states its safe, he fails to state that your recirculating water that's at thermostat level which is what is happening when you loop it. I know Of NO disadvantage to capping them off. some will say the motor will warm up a little quicker when looped also. I know of no race vehicles without heater core that run a loop , always capped if equipped with the provisions for a heater core on the intake and pump. I do recommend the usual 1/8" drilled hole in the thermostat . .

there was a long discussion on looping/capping the heater and the using or not using a bypass hose a few years ago over on the sbftech forum . I'll see if I can find it.

 

[jw0747]

Funnycar, toss the electric fan and install a fixed blade, engine driven fan like was on the Bronco when it came from the factory. A fan shroud also needs to be installed if you don't have one. Also install a 195 degree thermostat and with these three items go forth cooler than ever.

 

[ntsqd]

Just a foot-note about those rubber heater hose caps: Consider them to be a temporary - for testing only solution. They don't last. BT, DT; cost us a race and danged near the engine too. If testing proves it worth keeping capped-off then do what ever it takes to plug those holes with pipe plugs.

 

[savage]

Just a foot-note about those rubber heater hose caps: Consider them to be a temporary - for testing only solution. They don't last. BT, DT; cost us a race and danged near the engine too. If testing proves it worth keeping capped-off then do what ever it takes to plug those holes with pipe plugs.

I've been doing a lot of research on this and the rubber caps were a big problem for a lot of people. They were either cracking or blowing of do to pressure from the system, some people were taping and using screw in plugs, when it come to looping the heater hose or capping the water pump and intake its pretty even for opinions.

 

[ntsqd]

I think it's being over-thought. How many race cars (Cup cars, Desert cars, etc., anything except drag cars because they don't run long enough to count) do you see with heater core plumbing?

If you need or want a heater, run the plumbing. If you need the auxiliary cooling, run the plumbing. If you don't need or want either, permanently plug those holes.

 

[savage]

;D

I have a 1975 Bronco with a 392-450 hp. motor. It has a two core ( 1" wide) alumn. rad. This runs around 230 deg. going down the road and will not recover. Cant drive it in the weather here in Texas durning the summer.

Thanks

Funnycar:

Agree, so back to the main thread question, cooling problems. Funnycar,did you figure it out yet.