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Overheating

redbronc72

New Member
Joined
Feb 5, 2012
Messages
29
Ok so I was driving the bronco down the interstate the other day running about 70 mph. No big deal I used to run it 300 miles down I-85 at that speed or faster with no issue. All of a sudden i lost all my power it wouldnt go above 50 mph. I started smelling anti-freeze and my temp guage was pegged out. Blew the radiator hose off at the thermostat. Got it back home changed the thermostat since i figured it was stuck closed. checked the old thermostat and it works fine. now when i get above 2000 rpms it starts getting hot. under 2000 its fine. hasnt overheated again but ive been taking it real easy when i drive it. the neddle normally sits about 190 ish but as soon as i break 2000 rpms it jumps to the 210 range. drop back below 2000 and it cools down. cant swear to it but it seems like i have less power than before it over heated. this sound like a water pump problem to anyone? what direction do i need to start looking? Thanks in advance for any help you guys have.
 

blamejane

Bronco Guru
Joined
May 12, 2012
Messages
1,953
I would have thought thermostate too, but you've taken care of that. I too, will be interested in what other members have to say. Good luck.
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,604
Check your cooling system for pressure...you might have blown a head gasket which would contribute and/or cause both the overheating and the loss of power.

You can run a check on your anti-freeze solution to see if it has any combustion by-products in it...easy check, any garage should be able to check it.
 

jckkys

Bronco Guru
Joined
Mar 15, 2012
Messages
5,196
A blown head gasket is a common result of over heating, the head warps and the head gasket can't seal a bigger gap and water or compression leak through. There are two cylinders with no compression or coolant in the oil or a cylinder. None of these symptoms were mentioned. An engine scope or compression test would tell the story. The only parts in the cooling system affected by rpm are the water pump and fan. Neither would be hurt by over heating. I'm at a loss. Good luck.
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,875
I am guessing a head gaskit was lost when the truck overheated. but I would check that the spring inside the lower radiator hose is still intack and doing its job keeping the hose from sucking flat.
 
OP
OP
R

redbronc72

New Member
Joined
Feb 5, 2012
Messages
29
Thanks for the input so far, I havent had much time to mess with it yet. My oil looks clean and I'm not loseing coolant that I can tell. A local guy suggested i pull the radiator cap off while it is at normal temp and still running and check for bubbles. I did that and didnt see any bubbles. I have a 16lb cap by the way. I did drive it yesterday, did fine for the 10 miles to town about halfway back i got into it just to see what it would do, and again running somewhere around 70-75 mph and about 2600-2800 rpm it started getting hot. Makes me think water pump or a hose collapsing, that sound right? Maybe I need to bump up to a higher flow water pump? And would it still be worth getting the test to check on a head gasket?
Thanks guys
 

Bronco Junkie

So Cal Broncos
Joined
Feb 29, 2012
Messages
3,232
It has been my experience that if it was a head gasket...you would be losing coolant. Am I correct on this?
 
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