Coolant Flush

[Riptide]

We just went through hell getting the thermostat housing back on my girl's 1994 ranger with the 3.0 V6. In the process some crap got down into the coolant. Some tiny metal filings (mostly AL) and old gasket sealer that we had to sand off around the edges before putting the new seal on there. Even a little PB blaster may have made it's way into her coolant.

I want to flush the system and I want it done professionally. Are they going to have to take the thermostat housing off to do this? The one we just spent hours and hours with a drill getting fixed?

 

[rizoss16]

coolant flush? just a drain plug to take out at the bottom of the radiator from my experience

 

[H munster]

Do it yourself. Go to your favorite parts store and get a flush kit. Less than $10. Instructions are on package. And you are driving again within an hour.

 

[fordboi415]

Forget spending money on a kit, pull the return hose off the rad. It will be the bottom hose, let the hose hang freely allowing water to exit the block and plug the rad. return spout, stick a hose in the filler neck and turn that baby on and let it idle and flush everything out, also turn your heater on high so it flushes the heater core out as well, when the water starts comming out clean your done, put everything back together and fill it up with a 50/50 mix

 

[Deamers87ford]

really thats how you do it

 

[fastpakr]

I don't believe the heater controls have anything to do with coolant flowing through the heater core on the Ranger. You should have coolant moving through there at all times.

 

[alaskan155]

I don't believe the heater controls have anything to do with coolant flowing through the heater core on the Ranger. You should have coolant moving through there at all times.

yup the blend door conrols the heat,

 

[Riptide]

If it's not that expensive I'm going to pay to have it done. Seriously after spending as much time as we have just getting the housing back on I don't want to mess with it any more.

I've heard they have machines that are used to flush the systems under pressure now. I just wondered whether they would have to take the thermostat housing off in order to do that.

 

[Sasquatch_Ryda]

Most flush machines just go inline with the upper rad hose.

 

[LearjetMinako]

It is critical to have the heat controls on. Some vehicles (like the Ranger) actually shut-off the flow of coolant through the heater core when the controls are off.

And most shops machinces do use the upper raditor hose to flush the system. FYI, I recommend that you just do it yourself at home. Just make sure you recycle the old coolant.

Coolant flush:
1. Drain system
2. Add chemical cleaner and top-off with clean water
3. Run at high idle for 10min after thermostat has opened
4. Drain system
5. Re-fill with clean water and repeat step 3
6. Drain system
7. Fill with correct coolant mix of 50/50

For extra care, at step 6, leave the drain valve open and continous add clean water with the engine idling until the water comes out clean (15~30mins later). Then go to step 7.

 

[Riptide]

If it's less than $80 or so I'll have it done. I'm not going to pay a King's ransom for something like this but I'm willing to pay a bit just to avoid having to screw with it another day. We're putting her new fan in, tightening up the belt, and putting everything else back together tomorrow. If there aren't any leaks then we'll run with it for a week to make sure the gasket is OK and then I'm gonna flush the system.

 

[fastpakr]

It is critical to have the heat controls on. Some vehicles (like the Ranger) actually shut-off the flow of coolant through the heater core when the controls are off.

And most shops machinces do use the upper raditor hose to flush the system. FYI, I recommend that you just do it yourself at home. Just make sure you recycle the old coolant.

Coolant flush:
1. Drain system
2. Add chemical cleaner and top-off with clean water
3. Run at high idle for 10min after thermostat has opened
4. Drain system
5. Re-fill with clean water and repeat step 3
6. Drain system
7. Fill with correct coolant mix of 50/50

For extra care, at step 6, leave the drain valve open and continous add clean water with the engine idling until the water comes out clean (15~30mins later). Then go to step 7.

What year Ranger are you referring to that had control valves on the heater core?

 

[Sasquatch_Ryda]

98+ have them IIRC, called a 4 port vacuum operated heater control valve.

They have a tendency to leak over time as well.

 

[snake]

If you remove the LOWER rad hose and run water thru you are just running water through the rad-

The way I've always done it is to remove the UPPER rad hose, put a water hose in the rad, and let the waterpump pump water up thru the top hose and onto the ground while you replenish it thru the rad. The flow starts and stops as the thermostat opens and closes. When the water turns clear, run a few gallons of distilled thru it, and shut the engine off. Then drain the rad. Find out the cooling system capacity, and add 1/2 that amount of anti-freeze FIRST into the system and then crank the engine. Top it off with distilled and you have a perfectly flushed, full system with 50% water/antifreeze mixture.

edit- you run distilled thru the last few gallons because you can never get all of the water out of the block when you drain it- so whats left is distilled.