How do you flush the radiator on a 1987 bronco II?

Question

I was needing to know all the steps to flushing the cooling system...

Answer 1

My suggestion....

Disconnect the lower radiator hose from the radiator. Catch all the coolent you can as it has a sweet taste and is toxic and animals would love to drink it.... in other words.. you could kill your pet or someone elses.

Remove the top radiator hose.
Remove the Coolent intake on the engine where the thermostat is. Unless you KNOW the thermostat is good/new.. toss it! They are too cheap not to replace.
Clean the thermostat housing and engine block where it bolts.
Bolt the thermostat house back on but with out the thermostat or gasket (it's ok if it will leak some).
Reattach the top hose to the thermostate housing.

Now you have the radiator isolated. Use a rag/towel and wrap it around the end of a water hose to where the hose and rag will make a semi-tight seal in the top hose connection on the radiator. Turn on the water and let it run for a good while. You should run it until the water coming out runs clear.

Repeat the same process.. but attach the water hose/rag combination to the top hose that is connected to the engine. Again.. run the water until it comes out clear.

If your vehicle has an overflow reservoir, remove and clean it out as well. Coolent can move in and out of this reservoir if the system is still working properly and there by 'suck in' any dirt / residue that is left in there.
Remove the top hose and thermostat housing from the engine.
Examine the radiator hoses to determine if you should replace them. You have them off.. and they aren't that much... it might be a good idea.
Attach the bottom hose to the Radiator which should still be connected to the engine.
Attach the top hose to JUST the radiator.
Begin to refill the radiator/engine with coolent. Keep the end of the top radiator hose elevated to keep the coolent from flowing out of it.
Continue to fill the system until you see coolent coming out of the thermostat housing area.
At this point, reinstall the thermostat housing with the new gasket and thermostat.
Attach the upper radiator hose to the engine/thermostat housing.
Complete the filling of a the cooling system.
Don't forget to fill the reservoir tank if require.
Check for leaks.
Start the engine... check for leaks....
Move the vehicle and let it idle until it reaches the normal operating temperature. Check for leaks. By moving the vehicle you can more easily see if there are leaks as you will be in a 'dry area'.

THere ya go. This process will insure that no 'air bubbles' are trapped in the engine block and therefore creating an overheating issue.

IF you suspect the heater core is a problem.. you can discconnect the two hoses to it and flush it much the same way as the radiator. There is a valve on one of the hoses that regulate the water that you may have to manually operate or bypass to get the heater core to flush.

Good luck and I hope this helps!

Answer 2

Without making this too long, the way it's usually done is with a Flush kit , do you have that? If not , go to your local auto parts supply and get one , then they can tell you how to do it. The one i had before has a connector that you splice into one of the radiator hoses , then you connect a simple garden hose to it and with the radiator cap off you let the water flush it out . but first you would drain the radiator then refill it , adding the flush liquid , then running the motor for a bit.

Answer 3

I surely have a 1987 Bronco II, after I receives as a lot as accepted operating temp, it hesitates and then dies. I surely ought to tug off the line and wait a couple of minutes then it really is going to restart and that i'm able to proceed on for some better minutes till now it does it again. I surely have replaced both gasoline pumps, and the gasoline pressure is accepted by ability of the total adventure, 40PSI. I traced the lines, and there aren't any warm spots that may reason vapor lock, and there aren't any kinks or unusual bends contained in the lines. i'm at a loss the position to bypass from the following.

Answer 4

Drain the radiator into a bucket, close the petcock and refill with water. Run the engine with the radiator cap off so you see the water move through the engine when the thermostat opens, when the water stops moving, shut off engine and redrain the radiator. Then fill with radiator fluid to the containers specs. Take the bucket of fluid to your local garage that recycles and DO NOT poor or drain it on the ground!