Ever since I had my 89 7MGE rebuilt I have been chasing small leaks here and there on the thermostat housing and associated parts bolted to it. I got a housing that had no corrosion then I tumbled it fiberglass media until it looked like new. I warmed up (it’s freaken too cold to paint here) using a heater then painted it with Red Insulating Lacquer. Once everything is hard as glass and this stuff gets like that, I’ll paint it all white. I’m going to use white epoxy all throughout the engine bay a little at a time on brackets and things like that. I have used this method this in the past; it works great preventing corrosion long term. You can see I even painted the temp sensors, yes I know it’s an insulation paint, but once it’s warmed up I pretty sure the reading will be what they were, maybe more accurate since the brass surface isn’t corroded now. Also you’ll notice I painted the surfaces where the hoses go, this is really cool since the hoses don’t get welded to the corroding surface, and come right off. The surafce where the housing gets a gasket and bolts to the block will get slightly sanded on a surface place, being careful not to remove all the coating. The surafces the use the copper sealing washers are left bare metal. In about a year I’ll take it apart to show the results. In the past I did this everywhere I could on my old dodge 440 when I built it, especially the insides of the brand new expensive aluminum water pump housing, and aluminum water pump to which I had welded an anti cavitation plate to the impeller. After about two years I took it off to see, and everything was like I had just assembled it. No paint flaking, and what I really liked was no corrosion on the pump housing, which I had seen in the past. The bummer is I didn’t have a digital cam back then.
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455467301460466
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455471309206818
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455476498658098
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455475593475330
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455467301460466
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455471309206818
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455476498658098
http://picasaweb.google.com/jusrick/ThermostatHousingPainting#5561455475593475330