Timing Belt ON!! Now what about brown in the green??

[grantgsr]

Thanks to all of you over the last couple of weeks who have responded to my inquiries about my accelerator and choke and, most recently, my timing belt. I now have my timing belt on and all the timing marks remain correct even after rotating the crank. New issue now . . .

When I removed the radiator to install the timing belt, I had a pan under the hoses as I disconnected them to catch the coolant. I noticed as I did so that the liquid coming from the very small hose from the radiator filler cap to the overflow tank was brown, not orange brown like rust, just brown like chocolate. However the liquid from the big bottom hose to the radiator was clean and green. This 71 spider is new to me and the guy I bought it from hadn't really driven it much in the one year he owned it, so I can't diagnose much by how it was running before I changed the timing belt. Should I be concerned about the brown in the coolant? Does it indicate a blown head gasket or other serious problem? I plan to do a compression test soon after I get it running again, but what else can I test or check out or do I need to be aware of? As always, thanks for any help.

Grant

[So Cal Mark]

maybe the PO flushed the cooling system but neglected to clean the reservoir. I'd certainly drain and clean the tank so none of the bad stuff gets drawn into the radiator. Hard to say if it's rust or oil. Are there any signs of coolant in the oil?

[grantgsr]

I haven't changed the oil yet, that will probably be one day this week. I didn't see anything but normal looking oil on the dipstick and in the valve cover when I removed the oil cap. I'll report back when I see the oil drained out. Thanks.