Galvanized roof rust question

I currently have a really old galvanized metal roof. I noticed that there are different materials that were used on various parts of my roof to stop leaks. One thing I noticed was that anywhere where a tar-based material was used started to show signs of rust where as this other material that was used does not. My questions is what should I apply on a metal roof that stops leaks and does not create new rust. I used Henry 208 roof cement but I realized it started to rust around the edges of the tar patch. I know this may not be the correct material to use. Please help		Jon Galiza 2/29/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17139/find/
We will see if anyone else has anything to add.		Todd Miller Isaiah Industries, Inc. 3/10/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17140/find/
We don't do much in the way of re-coating so I am sorry I cannot be of more assistance.		Eric Novotny An informed customer is the Best Customer! 3/13/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17141/find/
My experience is that field-applied coatings intended to fix leaks offer at best a temporary benefit. The best resolution is to determine the source of the leak and address that, whether it is deteriorated or misinstalled material, flashings or sealants. Regards, David Stermer		David Stermer 3/13/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17142/find/
+1 Solid advice right there. Top coatings for leak repairs are band-aid only fixes and should certainly be thought of as temporary at best.		Eric Novotny An informed customer is the Best Customer! 3/13/2012	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/17143/find/

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