Originally Posted by Hotrod Lincoln
Try "water glass" (Sodium Silicate). It's available in quart bottles on Ebay at pretty reasonable prices. It's a very effective sealer on low-pressure cooling systems. I managed to seal a seep leak from the head gasket on the 503 GMC engine that I drove from Tennessee to the reunion in KC last summer, and Ed Pruss drove it on to Denver without any problems.
Jerry

Using my inner google-foo I was able to find that Bar's Head Gasket Repair contains sodium silicate without a bunch of extra additives. Cost is $11 locally, which isn't much more than e-bay.
http://barsleaks.com/product/head-gasket-repair/

Now to flush the system and disconnect the heater.

Thanks to Jerry & others.

Last edited by Fred T; 04/15/2016 4:50 AM.
Fred
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