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Radiator flush

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Inheritr6

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I just noticed my Tr6 is leaking coolant from the bottom radiator hose. I figured I might as well flush the radiator while I am replacing that hose but I have never done this before. I know something needs to be done because the liquid in the overflow bottle is black...

My question is, what are the procedures and products used to flush the system properly? I've heard a few different opinions about this and I just want to hear what you experts have to say:smile: Any advice would be greatly appreciated.

Thanks,

Dan
 
Aloha Dan,

I think any of the commercial radiator flush solutions you find at the auto parts store will do the job. Usually you pour it into the radiator and run the car for about 20 to 30 minutes. Open any valves leading to the heater if you have one so it is flushed also. When draining the system also open the drain petcock on the engine block to make sure fluid drains out of it. If it does not you can use a metal rod through the open petcock to poke around and loosen any sludge in that area.

If you are going to replace the lower hose, you should consider replacing the upper hose. While the system is drained and the hoses are off, check the thermostat and replacing it maybe prudent. A new radiator cap would complete a revamp of the cooling system.

With the hoses removed, a good flush with a garden hose may remove sediment the initial flush did not get or just moved to another spot, like the bottom of the radiator.

Even if you don't need antifreeze, I would recommend you use maybe a 25% antifreeze and 75% water mix because the antifreeze also contains rust inhibitors and water pump lubricants.

Good luck. It isn't a difficult job, just a little wet sometimes.
 
Hey Dan. Prestone makes 2 different flush chemicals and a kit that has a fitting to splice in a coolant hose for a garden hose so you can flush all the coolant passages after the chemicals work, but you have to either sacrifice the hose because you have to cut it or get a hose of the same dia. to spice onto.
But you might want to take the radiator completely off and bring it to a shop to get it really in shape. There's no telling what that Mississippi River water has done to it.
 
Hopefully, some of the "black" you are seeing are stains in the bottle.
You may want to run more than one flush before putting in new antifreeze. I bought a larger container that was enough to do two. Both came out with heavy rust.
 
Thanks for the info guys, I just bought some Prestone radiator flush that you are talking about. I will give this a shot this weekend.
 
Most rad shops will reverse the flow as well when they flush
I would pull rad as per the above. No time like it and well worth it!
Also watch for heater leaks as the flushing chems are corrosive. flush with ruuning water.
Agree on adding af when your finished works to dissapate heat

Watch your drains and disposal method as AF is toxic to your pets and the wildlife!
 
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