Alright, we went and picked up an engine from a 1989 F150. Story was the engine was rebuilt about 10 years ago, very little use, about 10,000 miles since rebuild.

History was it was used for camping for about 6 years, sat for 3 years. Last year the brother changed out the fuel pumps got it running then the trans went out.

When we got there the motor was oily all over, low on oil, oil was very black. But it did have replacement gaskets. Trans was out, mileage matched so we made a deal.

We got the engine on a stand, valve cover gaskets were all loose, distributor was loose (someone had adjusted, the retainer fell off the bolt and they just had the bolt holding it down). That would explain the oil on the block.

When we pulled the oil plug, a tablespoon or 2 of green came out then the oil. Pulled the pan and the bottom is pretty sludgy.

The rest of the engine looks fine, some drops of green under the pan on the side we rotated the engine around when we flipped it. No antifreeze in the filter or in the oil pump.

Any ideas? Thinking I need to pull the heads and regasket?? The hoses all had very green antifreeze in them when we pulled everything, but I don't know how any could have gotten into the pan unless through the loose distributor.....but that seems unlikely.

Any input appreciated.

Most likely cause; intake gaskets, headgaskets, timing cover or cracked head, start disassembling the engine and thoroughly inspect the gaskets and sealing/ mating surfaces, inspect the timing cover for cracks or damage from a faulty water pump impeller, try to find the culprit of the internal coolant leak, if you are unsure post pics up before you clean anything. Hope this helps