1965 Chevy C10/350 engine - This truck sat for many years, cranked up, sounds solid, filled w/water/ it went into oil pan why.

[Miquini]

Bought an old truck that sat 4 many yrs. Crank up well (w/o) radiator in it. When the radiator was filled with water, the water just ran straight into the oil pan.What's my next move & how do I fix the problem?

 

[Darkbreeze]

There is either a crack in the block somewhere, or a blown/rotten head gasket. Either way, it's a tear down and rebuild. Hopefully it's not the block but if it was stored with water in the block rather than an antifreeze/water combination, and you live in an region that see freezing temperatures, it's completely possible on an old casting like that to have cracked a hole or seam in the block.

It's one of the two. There is no other reason water would go directly into the oil.

 

[SKIPPY PB]

A new motor is probably the most cost effective solution for you. As they are cheap used and the diagnosis and R&R will probably be more pricey than a swap + good used motor. Some pressure tests and a comp test might help give you a little more information but not enough to be 100% with out the tear down.

 

[Darkbreeze]

If water is going directly into the oil, there is no need to do a pressure test, you already KNOW there is a leak. Compression tests probably aren't going to tell you anything either, as you can still have a good seal on the head gasket around the cylinder (Where no oil other than a very, very small amount not scrapped by the oil control ring, belongs anyhow, nor does coolant), good valve seating, free exhaust flow, everything required for good compression, and still have a head gasket that is blown between oil and cooling ports in the block/head, or a cracked block. If there is water going into the oil there is no other way to tell where or why it's getting then than to do a tear down.

 

[SKIPPY PB]

If water is going directly into the oil, there is no need to do a pressure test, you already KNOW there is a leak. Compression tests probably aren't going to tell you anything either, as you can still have a good seal on the head gasket around the cylinder (Where no oil other than a very, very small amount not scrapped by the oil control ring, belongs anyhow, nor does coolant), good valve seating, free exhaust flow, everything required for good compression, and still have a head gasket that is blown between oil and cooling ports in the block/head, or a cracked block. If there is water going into the oil there is no other way to tell where or why it's getting then than to do a tear down.

These tests can be used to help pin point what is going on. You know its internal to the engine, its whether he wants to get dirty or not. Obviously your not going to pay someone to do the tests for you as if you where down that road they would probably have other recommendations. If he or a buddy has the tools and feel like tinkering they can help aid him in pin pointing some locations. It's a shot in the dark but worth it if you have the tools lying around. He may be a weekend warrior. And I don't think this is his daily and only car.

A compression test can help give you a heads up on where to look a little harder. Im not saying you have to do but the tools are pretty cheap and regular common for people who are in the auto industry as a hobbyist. Again if you don't have access to the tools no its not necessary but not a complete waste of time to get the data from those tests. Im not sure how involved he wants to get with it. For the cost I would still suggest a new motor if he wants the challenge for a weekend project then why not.

 

[Darkbreeze]

This is what I do for a living. Compression and pressure testing won't tell you anything you don't already know, that there's a leak from the cooling jacket into the oil passage or pan. He already knows that. If there was a leak from cooling into the cylinder, there would have been steam out the exhaust. If there was leak from an oil passage into the cylinder, there would have been smoke out the exhaust. Since the coolant is going directly into the oil it can only be a failure in the head gasket between a cooling passage through the head and an oil passage through the head, or a crack in block that is allowing coolant to leak directly into the oil pan or an oil galley. That's it. There is no other possibility.

Since the OP has never bothered to respond, I'm closing this thread.