Radaitor Flush

[Bill Kemp]

I got a different veh. in Aug. and have been trying to get the maint. up-to-date.
I dont think the rad. coolant has ever been changed. (75,000 miles) Sort of brackish looking so I decided to do a flush.
There is a kit that comes with a valve to put in the heater hose line so you can hook up the garden hose and really flush it out. Usually you have to either cut the hose and leave the valve in or add pieces of hose to splice it in line. Not this time.... The heater control valve is positioned just right to be replaced with the flush valve. (I'm holding the flush valve over the heater cont. valve.) Used Prestone Flush followed by garden hose flush and refill w/50/50 antifreese & distiled" water. Also cleaned overflow tank.

 

[Kadarom Douhrek]

The downside being you don't flush the heatercore.

 

[Bill Kemp]

I dont know why it didnt. Had the heater on and engine running per instructions of the Prestone & hose flush sheet. Didnt that go through the heater core?

 

[Kadarom Douhrek]

Hmm, maybe I'm not getting how you hooked it up.
Your control valve has 4 connections right?
Did you put the flush valve between the hose going into the valve and from the valve to heater core leaving both outs attached?

 

[Bill Kemp]

The heater cont. valve is an "inline" valve as is the flush valve. I "replaced" the heater cont. valve with the flush valve. Which then get a garden hose hooked to it to provide the flushing action.

 

[Kadarom Douhrek]

I know how the flush piece works.
On mine, the control valve has four hoses.
One from the engine to the valve, from the valve to the heater core, back to the valve and then to the engine.

Which hoses did you put the flush valve on, or is the second gen heater control different?

 

[ipozestu]

Bill I had this set up for a little while. The T where you hook the hose up ended up cracking. Might want to watch for this in the future. A good flush can be accomplished with this though. Although it's just as easy to flush the traditonal way. Drain, fill, flush with heater on, drain it again, fill it with coolant and water then start it up and run it. This method always works well.

 

[VairKing]

With the T valve it should backflush through the heater core as well as the rest of the system. All areas should be flushed out..

 

[Bill Kemp]

I guess I should have said I "temporarily" replaced the heater cont. valve. I notice, after looking at the Haynes manual that the valve I temp. replaced is probably only on vehs. w/ auto climat cont.
There are two hoses that go into the firewall. I used the one closest to the pass. side.
I used this flush method cause I've always felt the traditional way could easily leave some of the flush chem. in the system.

 

[skipc10]

I haven't used it in a while, but I made up an adapter from 2" dia or so galv pipe nipple (4-6" long and sized to fit the hose) to female hose fitting and disconnected the lower hose at the radiator. I clamped this thing into it and connected a garden hose.

Turn on engine, turn on hose and adjust flow to keep up with what drains (if you have high water pressure, monitor the upper hose and don't try to pressurize the system). The flow through the heater keeps it from ever being really pressured at reasonable rates.

The water pump flushes the heater, and all water taken into the block is fresh! The old stuff comes out the lower radiator fitting.

After a few minutes, turn engine off and keep rinsing until the stat closes, which will be quick (you'll know when by flow). You'll have a cool engine and a complete flush by then, and no cuts to heater hoses or components to fail.

I did it the old way last time because I couldn't find this adapter (I will when I get a chance) and it took 3 drain-and-refills before it came out uncolored water....

 

[Kadarom Douhrek]

Originally posted by Bill Kemp
I guess I should have said I "temporarily" replaced the heater cont. valve. I notice, after looking at the Haynes manual that the valve I temp. replaced is probably only on vehs. w/ auto climat cont.
There are two hoses that go into the firewall. I used the one closest to the pass. side.
I used this flush method cause I've always felt the traditional way could easily leave some of the flush chem. in the system.

So the heater valve is only on one hose?
Does it just block the flow or redirect it?
That's what is confusing me.

On first gens the valve switches between coolant runing through the heater core and just looping through the valve.

Open, water flows in bottom left, out top left, in top right, out bottom right.

__| |_| |
| _ / __|
| | | |

Closed, water flows in bottom left, out bottom right.

__| |_| |
| _ \ __|
| | | |


Not sure what I was thinking in my first post.
Now I just want to know how your valve works.


Stupid second gens with your fancy valves.

 

[Bill Kemp]

The valve in the first pic is inline before the cont. valve behind the firewall. It just opens & closes so the heater doesnt come on untill there is hot water to heat the interior. On Xs without that you would need to have a short piece of hose to go from the firewall fitting to the T flush valve which would be connected to the hose you just took off the firewall.

 

[Kadarom Douhrek]

Ahh, on ours the control valve is where that thing is on yours.
That's why I couldn't figure out how you where replacing it and still getting water through the heater.
Although I still don't see why they would have that cutoff instead of just keeping the valve in bypass mode until warm.

And yeah, I just use a short piece of tubing to "splice" the T inline with the valve.

 

[lonestar]

Originally posted by Kadarom Douhrek
Open, water flows in bottom left, out top left, in top right, out bottom right.

__| |_| |
| _ / __|
| | | |

Closed, water flows in bottom left, out bottom right.

__| |_| |
| _ \ __|
| | | |

It's not that hard. Just connect the "T" in between the bottom left and the top left. Fresh water flows into the heater core, into the valve, out the valve just like regular flow when the heater is on.

Or even easier, just connect the garden hose straight to the heater core inlet..