Overheating

[shuagriz]

I need some help/ideas. I just bought my bronco a few weeks ago and it started to run really hot, verge of overheating. The needle on the gauge is running between the end of the normal and the line rite before the red when driving. It stays in the midlle of normal fine as long as it is just sitting and idleing until you drive it around. I've changed out the thermostat and the fan clutch with no good results. Any ideas?

 

[Yardape]

You could have some of the cores plugged in the rad, run the truck until its hot, then feel around on the rad for cold spots, this is easiest using a digital thermometer gun thingy. If this is the problem smile and have a beer, your fix is easy. If not...... you may very well have a blown headgasket. The head gasket can be fixed by a reasonably competent weekend wrencher, just dont fall into the trap of "well since your there, yank the engine and do the bearings, hey what the heack how often is the engine out, might as well do the rings, hey the pistons are out, maybe a little machine work, **** why not build a stroker, the heads are off why not slap a set of brodex heads on there........ and on and on." Just fix the head gaskets (if thats the problem)

 

[Yardape]

Another thing I should add, I had an 83 F-150 with a 302 that had a whole lotta crap wrong with it. It over heated alot, I tried everything I could think of. My mechanic guru friend told me to check the rad cap, make sure its holding to the correct pressure.(buy a new one they are cheap). That wasn't the problem. Then he suggested a pressure issue elsewhere, eventually I checked the frost plugs, one had a pin hole in it which caused a loss in pressure, which caused overheating. I replaced them all and the problem was solved. They were in very rough shape, everyone of them were ready to rust through.

 

[Yardape]

My Bronco used to overheat, has a 3 inch body lift and had no shroud. I cut up a shroud that I had laying around and put the rad from my other Bronco in it. Old one was quite muddy. Never even hits the halfway mark anymore on the temp guage.

 

[Stubby1971]

i would suggest starting with the easy stuff- check the upper and lower radiator hoses to see the difference in temp- make sure that the coolant is flowing through the radiator and that enough coolant is flowing. make sure you have a fan shroud that isn't in shreds- make sure the thermostat is working properly, does it have a clutch on the fan? is it the rite fan for the vehicle? does it run cooler when you run the heat on high? if it's a head gasket you'll end up with more problems than over-heating- check the oil just to make sure none of you coolant is ending up there- also check the condition of the coolant- does it appear milky( that would be oil), is it clear( no coolant- just water), make sure it's a good 50/50 mix. let us know what you find- and ask more questions as you work through it- one other thing- check and see if the gauge is working rite- we all know it is, but you should still check it

 

[Broncosaurus!]

Mine is doing the same thing, but its like -5 here and I don't work in those conditions, how can i test the pressure of the system?

 

[shuagriz]

Mine is doing the same thing, but its like -5 here and I don't work in those conditions, how can i test the pressure of the system?

Pressure test is easy if you have a pressure tester. Its just a pump with a gauge on it that connects were your cap goes. With the vehicle off you pump it up till it reads the spec pressure for your system. Then check for leaks and see if the pressure goes down. If you lose pressure then there is a leak some were. You might be able to get the tester at Auto Zone or some place like that. They might loan them out as a specialty tool. not sure though. Hope to find out since I need to pressure check my system.

Thanks for the help and ideas

Any who as for my Bronco, Here is what I've done so far in order:

1. Checked coolant level and condition. No oil in water or water in oil.

2. Checked fan shroud condition. It was good.

3. Coolant not good mix so I flushed the system and and refilled with proper 50/50 mix

4. Found that the upper and lower hoses were in bad shape while Flushing the system so I changed them.

5. Put on a new radiator cap with O.E. spec for pressure

6. Changed the thermastat with O.E. spec one. (installed rite way)

7. Noticed Fan clutch leaking some fluid. Changed fan clutch.

After I drove it today to see if the fan clutch fixed it, I noticed the top of the radiator was realy really hot. hotter then the upper hose by a lot. Then I noticed when I got home tonight that there was some coolant on the ground but I can't figure out were it is comming from. Doesn't seem to be from any hoses. I'm starting to think the radiator its self might be the issue. I'm going to try and pressure test it tomorrow and find the leak, but I'm thinking it might be comming from the seal were the tank and core mate up. Well its to dark to do much now and I'm to tired. I'll let everyone now what I find out tomorrow. Any one have any more words of advice?

 

[Yardape]

If there was "fluid" leaking from your fan clutch, I'd say your water pump might be done.

 

[KJEfting]

A very quick and easy way to check for obvious pressure loss is to check the upper radiator hose when the engine in running and hot. If the engine is running and at operating temperature, the upper hose should be pressurized enough that it's pretty solid. If it's not, then you're obviously losing some pressure somewhere.

 

[miesk5]

the rads have a plastic shell crimped onto an aluminum core so...the radiator plastic side seam leaks, esp. during engine cool-down period/overnight - our's leaked @ 50k miles - look for leaks after engine has cooled down, esp overnight.

some say they fixed it with epoxy or silicone but that is a temp fix

 

[shuagriz]

Ok, well I got a pressure tester from Autozone this morrning and found the leak. Before I was even at 10 PSI I could here a hissing sound from were I thought the leak was comming from. Then I looked down and sure enough there was coolant ******* on the ground. Turns out the radiator is leaking around the seal were the tank is crimped to the core. Its just below the bottom of the tranny cooler. I let the pressure sit and bleed off till it somewhat stablized and it was at about 4 PSI. Goes to show that a static small leak, when at operating pressure turns into a big leak and problem. I should have pressure tested the system, after fixing the coolant mix, didn't work. Oh well, would have had to change all that other stuff before summer anyways. I'm going to try and order a new radiator from NAPA at school today. Student discount is pretty good. Hope this will fix the problem, so my Bronco will be more then a lawn ortament. :wacko:

 

[shuagriz]

A very quick and easy way to check for obvious pressure loss is to check the upper radiator hose when the engine in running and hot. If the engine is running and at operating temperature, the upper hose should be pressurized enough that it's pretty solid. If it's not, then you're obviously losing some pressure somewhere.

I did this and the hose felt solid but obviously there was a pressure problem. From what I know, and have learned this is a good quick check but should never be substituted for an actual pressure test.

 

[shuagriz]

I got a new radiator Yesterday and put it in. The dang thing is still overheating!!!!!!!!!!!!!! I'm about to go insane!!! Well I think I'm going to change out the water pump today. If that don't fix it I don't know what will.

 

[miesk5]

I got a new radiator Yesterday and put it in. The dang thing is still overheating!!!!!!!!!!!!!! I'm about to go insane!!! Well I think I'm going to change out the water pump today. If that don't fix it I don't know what will.

darn it!

too bad, but you did have a leaky rad at the seams, right? hate to see pals use $... the water pump laek can be @ "weep hole" - Check for shaft seal failure by carefully inspecting the water pump weep hole. When a water pump is new, some seepage is normal in the initial hours of operation as the seal seats. Other than that, any leakage that occurs is due to seal failure and the pump needs replacement. There may be tell tale trails of rust, calcium and coolant deposits on the water pump housing with the weep hole as the origin.

Detect a worn water pump bearing by checking for side-to-side play at the shaft. There should be no perceptible play as you apply hand pressure to the shaft. Accelerated bearing wear is characterized by screeching or rumbling noises coming form the water pump housing. If any of these conditions exist, the bearing is worn out and the pump should be replaced

gl!

 

[gnarly_bronco_kid]

I'm having the same problem with my truck. It's fine if I'm just cruising around town but as soon as I pop it into 4 wheel drive and start throwin mud the temp goes way up. So I bought a lower temp thermostat, it helped a little bit but still didn't do the job. I did however put a skid plate right below my fan so that my fan won't throw mud everywhere. I'm thinking maybe alot of my air came from underneath my truck and my skid plate is blocking it. But I still don't know? Oh and how much was your new radiator and or water pump, I know just the radiator didn't work, but let me know if the new water pump does.

 

[shuagriz]

I'm having the same problem with my truck. It's fine if I'm just cruising around town but as soon as I pop it into 4 wheel drive and start throwin mud the temp goes way up. So I bought a lower temp thermostat, it helped a little bit but still didn't do the job. I did however put a skid plate right below my fan so that my fan won't throw mud everywhere. I'm thinking maybe alot of my air came from underneath my truck and my skid plate is blocking it. But I still don't know? Oh and how much was your new radiator and or water pump, I know just the radiator didn't work, but let me know if the new water pump does.

The radiator was $140 and the water pump was $48. I could have got a water pump cheaper but, I got a new one, not a rebuilt piece off crap

 

[shuagriz]

Well I got the water pump in and my problems are over. The needle stays on the R, the hottest it got was to the front of the M. And there was much rejoicing............... Yeeaaa. The old water pump had no water comming out its weep hole or any side to side play. The impellers were fine, so it must have just started to slip. Hmm, well I shouldn't have any more cooling problems in the near future, everything is new, knock on wood. Thanks for the help and I hope this might help someone down the road trying to figure out a cooling problem. You guys rock! /emoticons/[email protected] 2x" width="20" height="20" />

 

[Yardape]

Congrats