Opinions on radiator flush ?????

[BobT-47P15]

I bought some Prestone radiator flush liquid, planning to use it on the Plymouth. Any reason it would not be good to use it?? Would seem as if it would help clean the system a bit.

[55 Fargo]

Hi Bob, some folks believe the chemicals may be a little harsh for these old rads, and once used could end up with leaky rad cores. Not sure if this would work or not in your rad. Are you having cooling problems. What about just plain water and flushing the entire system, then don't forget to fill with antifreeze and de-mineralized or RO water. Fred

[Norm's Coupe]

Bob,

I flushed my radiator out when I had it off the car during the engine rebuild. All I did to flush it out was stick the hose in the top and let it run out the petcock at the bottom. Haven't had any problems with cooling or the radiator. That was in 1998. So all I used was plain water.

[bob westphal]

I have used the flush you're asking about. If anything, I thought it wasn't strong enough. The new aluminum radiators are more sensitive to harsh chemicals than our old copper ones. You shouldn't have any problems if your system is in good condition. It could eat out old stop leak material already in the system, though.

[BobT-47P15]

Comments such as these are the reason I asked. Have not had any problems with the cooling system.....seems to work about right. I actually do not know if there is a thermostat, but there probably is. Don't think any stop leak stuff has been used. Don't know how much gunk has accumulated in the block as have not changed coolant for a while. Maybe I'll just skip the stuff and flush with water. Any further thoughts appreciated.

[Plymouthy Adams]

I usually flush with clear water...back flush if there is a seious enough amount of sludge...

My method is to remove the thermostat so you will not have to wait to eng temp to circulate...I also turn on the heater control valve to route water through it as the same time. I remove the upper rad hose, place garden hose into the radiator fill spout..start engine..open the flow of water till you get to the point that the engine is pumping out what you are putting in at the hose..route your open top hose away from the fan and the distributor.....let run for a spell till all water returning is clear..or if clear to begin with..just run about 15 minutes to be sure. Replace the thermostat and upper hose, use new gasket on thermostat...fill with minimum 50/50 mix...if in a real cold area...60/40 may suit your fancy..