Date:         Sun, 4 Apr 2010 19:13:44 -0500
Reply-To:     mcneely4@COX.NET
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dave Mcneely <mcneely4@COX.NET>
Subject:      Re: Radiator flush
Comments: To: Zoltan <thewestyman@GMAIL.COM>
In-Reply-To:  <F4727FEAA65945EEA6B22181DB17E825@ZoltanPC>
Content-Type: text/plain; charset=utf-8

---- Zoltan <thewestyman@GMAIL.COM> wrote: 
> I don't remember seeing a posting about how to flush a radiator to get out all the deposits.  And what kind of liquid to use to free the deposits up.  I can hook up a separate pump with two different hoses to it, so only the radiator would be involved.  Do I need a certain pressure to push out the dirt?  Do I need to do it both direction?
> Anyone know anything about this kind of work?  Do I need a filter with flush like that?
> I have tried to hook up the garden hose, but other than the water going through freely, I did not achive any positive result.
> Maybe I have to soak it with some liquid inside for a day to lift the deposits, then flush?
> Zoltan

Parts houses carry special chemicals for flushing, and special hose attachments that are supposed to flush the cooling system better than simply draining it.  The chemicals are packaged and sold by the major antifreeze brands like Prestone.  Most of the chain shops like Firestone advertise "power flushes" and highly recommend them.  A radiator tech who runs his own shop told me it's a waste of money (both the chemicals and the power flush).  He said to run fresh water through until it runs clear, then seal the system, run the engine to hot, drain, and if clear, it's probably good.  If not, then you probably should just buy a new radiator.  Radiator shops still do what is called "rodding out" the radiator, which is running thin metal shims through the radiator passages to clean them out.  They also will immerse your radiator in a chemical bath to help to clean it out, preparatory to the "rodding," and they will for some radiators solder a new tank and new fittings on to the old core.  Of course, those radiators with plastic tanks are not so easily repaired as are all metal ones.

The price for all this comes to half or more the price of a new radiator.  And, some new radiators are copper, rather than aluminum, which makes for better heat exchange.

David McNeely