I posted a couple of times last week or so. I've got two '83 GL wagons. I THOUGHT I had a wrecked one with a good engine, and a good one with a blown head gasket.
I had all the classic symptoms or so I thought. Overheated, couldn't keep coolant in it, couldn't see where the coolant was going. There was ugly gunk in the oil filler neck, it looked like there was coolant in the oil. I parked it, and they both sat in my yard for two years. Now I want to get one going again.
So I did a leakdown test on both engines, and was surprised to find the one with the blown head gasket had better readings. That did not deter me from proceeding with pulling the heads, as some posters indicated that I could still have a head gasket leak with those relatively good leakage percentages.
After I had the intake off and thinking about it, I started getting scared. What if I pull the heads off and it doesn't look like there is anything wrong? I could waste all that time and two good head gaskets for nothing.
It gets better. Before yanking the heads off, I came up with the idea of pressure testing the cooling system. I made two flat metal plates and used two new intake gaskets to plug the intake manifold. I plugged both outlet hoses from the water pump and all the other fittings and hoses common to the cooling system. I pressurized the cooling system to 20 PSI and guess what? NO LEAKAGE. The damn thing sat for an hour with my pressure gauge glued to 20 PSI.
I am now afraid that I over reacted to the overheating and assumed that I had a bad head gasket when I really didn't. Could the residue in the filler neck just be from condensation? I now go wipe the dipstick off and put it back in, and the oil looks brown instead of black, but what does that mean? Also, the spark plugs look all the same and normal.
Sorry for the long post, but what do I do now? I've got the thing all ripped apart, should I proceed with the head gasket job? Or should I put it back together, change the oil, and do a better job of troubleshooting?