Overheating

[Pacopico]

New to the bronco, not new to engines...

Here's the setup 351W (mild), headers, 3-row raidator, WH Fan shroud, 7-blad flex fan (3" spacer - it's cirrect in the shroud) new (and working) 180 thermostat, 13lb cap, "cowl induction" fiberglass hood (cutout in rear).

What is considered overheating for the SBF (351W)?

The truck will run at 55/65 at ~190 (2800 rpm)
when keeping up with SoCal traffic (75/80 - 3400rpm) it will run up to ~200 and stay put...if you come off the freeway and immediately sit in traffic it will stay at ~200 until you get going again (normal road speeds) and cool back down to ~185...Does this sound normal to anyone?

As well when doing some crawling it likes to get up to ~205/210 and takes a while to come down...

It never blows water out of the overflow, and doesn't loose any coolant (ie. pressure leak).

Would adding an auxilliary electric pusher help...or any other ideas?

I searched and saw some mentions of cutout inner fenderwells - pros and cons? (I do use it off road, and see mud only sparingly).

Thx! :-*

 

[Skuzzlebutt]

All Broncos should have cooling as good as yours.

 

[76Broncofromhell]

I would say don't worry about it. If you have an auto sitting in traffic will cause the fluid to heat up which causes the coolant temp to go up. 200 isn't bad anyway. As long as it doesn't go over about 230 I wouldn't worry too much. Also I have found flex fans don't cool as well as the stock fan, and electrics aren't nearly up to par. For this reason I am going back to the stock fan with a non-leaking new 4 core.

 

[74bronc]

The fact that the engine cools down again after moving, that means you don't have a cooling capacity problem, but you have an air moving problem, like every other bronco owner out there. Your temps don't sound bad at all. If you want to stabilize it even more, I would put a pusher electric on it with an automatic thermostat. Also, if you have an auto, I would consider a stand alone cooler and fan for the tranny, therefore moving the heat from the auto tranny away from the radiator. If you really want to pull some serious air, put a fixed pitch fan on the thing. BC Broncos has them.

 

[Hnrys69]

Hmm. Yours sounds kinda like mine. Heres my theory on it.... I dont think the stock temp gauge is accurate. Seems to be off to me as I have seen mine jump over 230 fast and still no boil over and under the hood doesnt seem to be that hot. I think its ok. I did add a 10inch pusher fan on mine to give me the peace of mind of being able to toss the switch and move more air...

 

[MKD]

From page 12 of a 1973 Owner's Manual:

"ENGINE TEMERATURE GAUGE -- The temperature (TEMP) gauge indicates how hot the engine is. Your Bronco engine is designed to run hot for more efficient use of fuel. Therefore, the temperature needle will move to the right side of the operating band of the gauge as the engine warms up.

There is no danger to the engine unless the pointer goes to 'H' and stays there. If this happens, stop the engine and let it cool..." ...blah, blah, blah.

(Thanks to http://www.broncohio.com/tech/73broncomanual/73man-12.JPG)

So, maybe this means we don't have to be so worried about 190+ temps?

 

[Pacopico]

Thanks for the responses...I have an aftermarket gauge (autometer, readings verified w/raytek infrared heat gun), so I know what I am seeing is real

I think I will add a pusher (same as HNRYS69), just for piece of mind...and eventually I intend to go to a seperate closed transmission cooling system...Sounds like I am on the right track!

 

[chuck]

Any of the things that 74bronc mentioned will help but 205 is not too bad. 185 would be better but 205 is not bad, 230 is bad

 

[mvbronco]

Boy, that make me feel better. I thought I was running way too hot. I have a 76 completely stock with an auto and was concerned when I was getting up to 205-210 in stop and go so. cal traffic. I run 175-180 any other time. I'm getting ready to put a WH 4-core to see if it helps. Maybe I shouldn't be so concerned after all. I'm still changing the radiator, but I feel better now. Thanks All!!!