thesnake
Bronco Guru
- Joined
- Jun 20, 2001
- Messages
- 3,503
As with a lot of older vehicles, the Bronco cooling system is prone to overheating, if not properly kept up. Some of the sources of overheating are listed below:
Not enough coolant in the radiator. You should check the coolant level every 200-300 miles or so. If you have the coolant recovery reservoir, mounted on the passenger side front wheel tub, you can judge the level from the markings. If it’s below the low mark, check the radiator after it’s fully cooled. It should be 3/4 to 1 ½ inches below the radiator neck and add coolant to bring the level up. If the level is really low, then there may be leaks in the system.
Where to check for leaks: radiator hoses, heater hoses, hose clamps, bypass hose, heater core, thermostat housing, water pump, freeze plugs and the radiator. It also wouldn’t hurt, if you do have a leak, check your engine oil to insure it’s not watery, which would give you an indication of a blown head gasket at the minimum to a cracked head or cracked block.
Another cause for overheating which I’ve had happen to me before, the fan belt not being adjusted properly or the belt is bad.
If the radiator is blocked (dirt, mud, (Nebraska)bugs), this can lead to overheating. The radiator should be hosed off every so often.
If you’ve been working on the engine, incorrect timing could be a issue, causing overheating.
Another source of overheating is a bad thermostat. To test it you can pull the thermostat out and heat it in a pan of water and if it opens it’s good, if it doesn’t open all the way or not at all it should be replaced.
Damaged fan blades can cause overheating. Depending on how your bronco is set up, running just an electric fan, may not be enough to keep your bronco from overheating. Running without a fan shroud is a biggie also.
Sometimes it’s the radiator cap that goes bad, I've dealt with this, you can have the coolant system pressure tested, but sometimes that's a hassle, I've just replaced the cap before and that has been all it took to cure the problem.
Insuring that your C-4 (or other auto transmissions) has plenty of tranny fluid and that the lines aren't leaking, could also be a preventive measure to insure that you avoid overheating.
Putting in a beefer engine (hi-po) can be a cause for overheating, if running the stock radiator.
Any one of the above could cause overheating and driving your bronco hot for any period of time could cause severe damage. Checking hoses, water pump, hose clamps, coolant levels (and getting that faulty gauge fixed), could prevent blowing a had gasket, cracking a head or the block.
For this article I browsed the 66-77 Chilton's and my own personal experience. While not all inclusive and detailed, this should give an idea of what is some possible problems and some solutions.
Not enough coolant in the radiator. You should check the coolant level every 200-300 miles or so. If you have the coolant recovery reservoir, mounted on the passenger side front wheel tub, you can judge the level from the markings. If it’s below the low mark, check the radiator after it’s fully cooled. It should be 3/4 to 1 ½ inches below the radiator neck and add coolant to bring the level up. If the level is really low, then there may be leaks in the system.
Where to check for leaks: radiator hoses, heater hoses, hose clamps, bypass hose, heater core, thermostat housing, water pump, freeze plugs and the radiator. It also wouldn’t hurt, if you do have a leak, check your engine oil to insure it’s not watery, which would give you an indication of a blown head gasket at the minimum to a cracked head or cracked block.
Another cause for overheating which I’ve had happen to me before, the fan belt not being adjusted properly or the belt is bad.
If the radiator is blocked (dirt, mud, (Nebraska)bugs), this can lead to overheating. The radiator should be hosed off every so often.
If you’ve been working on the engine, incorrect timing could be a issue, causing overheating.
Another source of overheating is a bad thermostat. To test it you can pull the thermostat out and heat it in a pan of water and if it opens it’s good, if it doesn’t open all the way or not at all it should be replaced.
Damaged fan blades can cause overheating. Depending on how your bronco is set up, running just an electric fan, may not be enough to keep your bronco from overheating. Running without a fan shroud is a biggie also.
Sometimes it’s the radiator cap that goes bad, I've dealt with this, you can have the coolant system pressure tested, but sometimes that's a hassle, I've just replaced the cap before and that has been all it took to cure the problem.
Insuring that your C-4 (or other auto transmissions) has plenty of tranny fluid and that the lines aren't leaking, could also be a preventive measure to insure that you avoid overheating.
Putting in a beefer engine (hi-po) can be a cause for overheating, if running the stock radiator.
Any one of the above could cause overheating and driving your bronco hot for any period of time could cause severe damage. Checking hoses, water pump, hose clamps, coolant levels (and getting that faulty gauge fixed), could prevent blowing a had gasket, cracking a head or the block.
For this article I browsed the 66-77 Chilton's and my own personal experience. While not all inclusive and detailed, this should give an idea of what is some possible problems and some solutions.
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