hickokcpa

I recently replaced the incorrect intake manifold with the correct on my 1973 small block. I got it put back together and added coolant to the radiator and noticed the coolant was leaking from the front of the pan near the timing chain cover. I figured it was a bad water pump gasket or timing cover gasket. Since this was going to set me back I decided that while I was at it (of course), I would replace the oil pan gasket and rear seal. When I opened the drain plug a mixture of oil and coolant rushed out. Prior to replacing the intake the car ran fine. I guess my question is, is it probable that I didn't get the intake sealed correctly and thus my leak? I read a few threads responding to similar problems suggesting it was the head gasket. However since it was running fine prior to my disassembly, I find it hard to believe it's the head gasket. Also, what steps do I need to take to cleanse the engine of the coolant that leaked in. Thanks!

rbowman

Since there was no issues before replacing the intake gasket, my guess something went wrong when this was performed. As for getting the coolant out of the oil pan, just replace the oil and filter. If you choose you can change oil and filter again after a short run, at least it would give you a little piece of mind.

Ron

hickokcpa

Thanks Ron. I needed some reassurance. The oil I drained out has never been run through the motor. I changed it before I starting tearing in to it. When I drained it, it seemed to pour out a little thinner than I was accustomed changing used oil. Now I'm wondering if coolant is actually in there. Hard to tell.

resdoggie

Oil is less dense than coolant so when you remove your drain plug, the coolant will flow out first if there is any significant amount.

Roozstr

Are you sure it isn't the coolant that ran into the crankcase when you took the intake off? Trick is to leave the oil plug out and do an oil change after you put the intake back on.

hickokcpa

So put the intake on, take out the plug, and add oil? Just run oil through it?

hickokcpa

Yeah, it sure looked like it was diluted but was hard to tell for sure. I guess when I get the water pump back on and the gaskets replaced, I'll add antifreeze back in and see if it leaks out the oil drain. Before I remove the intake again.

Roozstr

An Intake manifold has coolant running through the front and back of it. When you remove it coolant runs into the lifter valley and then into the oil pan. This is normal. No getting around it. You just need to change the oil after the intake is replaced to make sure all the coolant is out of the crankcase.

JimLentz

If you leave the drained oil sit in a container a few minutes the coolant will separate out and will come to the top of the container. If you put it in something clear you would know right away if there was coolant in it and about how much.

hickokcpa

Ok got it. I knew I was missing something there. Thanks!

hickokcpa

Great idea. I'll try this. Thanks!