My newly acquired 88 Bronco 5.0 AOD w/ 200,000 miles had been parked in a field for the last 5 years. I put a battery in it checked the fluids and drove it home. When I shut it off I could hear & smell it was overheating. The gauges did not work for some reason. I changed the thermostat 195 deg, removed the upper & lower hoses and flushed the radiator out with water, checked the timing 10 deg. The upper hose would get hot but the bottom would stay cool. Both heater hoses were equally hot. No leaks from the water pump. Please help I don't want to replace parts until resolved like I normally do.

 

well you did do a start on the replaced thermostat. You will need a good block flush to get the grime out of the block though.

 

The first thing you should do is VERIFY that it is overheating.
Don't assume.
Do not throw parts at it to solve a percieved problem. Diagnose it.
Aftermarket gauge will verify the temp.
The condition of the hose temperatures sounds somewhat normal. The lower hose will be the cooler of the hoses.
If it sat for 5 years with no driving, a system flush would be in order.

 

Thanks I will try that as soon as I can.

 

You might check to see if the fan clutch is engaging. Once the radiator gets hot the clutch should grab the fan and it will make a loader roaring sound than when it is just free-wheeling.

With the engine off - duh, but I never know - try to spin the fan. It should move freely, but have a somewhat sluggish heavy feel. If it spins with no effort at all the clutch may be worn out.


Calvin

 

I back flushed it last night and dumped in some radiator flush, I will check out the fan when I get home. Thanks

 

OK, I took it for a drive around town and it started heating up, when I would accelerate or go up hills it rattled like a diesel. Timing? I'm not sure if it is set right I took the previous owners word it was right. I tried to check it but could not read the numbers ( too rusty ). Anyway I could not hear the fan clutch kick in, checked the fan while engine was off, thanks for that advise and it was the same hot or cold. So timing and fan clutch? I'm in Utah @ 5500 ft. The sticker says 10 deg is that right for this elevation? Also when I pulled in the driveway the engine died wouldn't start and was puking fluid out the overflow.

 

I like to mark 10 and 12 degree btdc with white typing correction fluid to make it easy to time. I don't know about altitude so adjust until it does not knock. You did not mention replacing with 50/50 antifreeze. Fan clutch sound very suspicious especially if over 120K imo.

 

bypass the heater core, double check timing with spout connector removed. perhaps the water pump is bad as well

 

inst there a sensor/diaphragm that allows the flow of fluid through the engine. that could be a problem. my pops car was overheating and that fixed the problem, took 10 min and was around 10 bucks. don't know how that would relate to the other problems tho.

 

I am having a similar problem I have replaced the radiator, thermostat, waterpump, and hoses after dropping a new crate engine. It was running fine but seems to be overheating and dont know why. I did noticed the petroleum jelly that i packed the oil pump with was sticking to the bottom of my breather cap that connnects to the valve cover. I do not really know how to create my own thread but any advice would be helpful.

 

Welcome to FTE and the Big Bronco Forum. We will do our best to get you the most accurate info we can.

The suggestions above about the fan clutch should really be high on the priority list. Let the truck sit for a while... basically with the engine cold... and NOT RUNNING... reach in and give the fan a spin by hand. A fan clutch in good shape should only allow about one full revolution even with a good strong spin.

As for creating a thread of your own, go to the Big Bronco Forum and look for a button near the upper left corner "New Thread". Click and follow the prompts.

 

It's too bad cguest didn't finish. He probably had a blown head gasket.

 

corpmanup, it might be your thermostat is in backwards, spring goes toward the engine.

Did you get a long block or short block?

 

I have fixed the problem it was a hose that came just the tinyest bit loos when the truck was running it doing great just need to work on the body now