Cracked 389 Block?
 

Are these blocks known to crack with overheating or detonation?

This engine is showing condensation on dipstick and water vapor out valve cover filler cap.

Water level is low and leaks out water pump shaft seal when filled, so it was probably run with too little water.

Going to pull the heads and look at the head gaskets and bores.

Most likely, gaskets perhaps with warped components that the gasket is supposed to seal--manifold to head, head to block, timing cover to block, etc.

Could be cracked casting(s)--heads, block, timing cover, intake manifold.

Could be corroded timing cover.

If you yank out the plugs, and one looks steam-cleaned, you'll have an idea where the problem is. Otherwise..."good luck" with the examination.

My bets on failed head gaskets!

I hope so.

There is a lot of blow-by so a good chance a ring is broken or bore is worn.
Back before, when the oil was clean, I had noticed a lot of old oil sludge under the valve cover.

Then I let 2 different people store the car with the keys, so who knows what happened.

Will tear it down because I don't want to let water potentially sit in a bore too long.

It is actually a 2bbl 326 so I really would rather not put the money into a full out machining and rebuild potentially including new pistons, valves, guides etc.

Getting my cars confused.

A lot of those 326 , 389 and 421 motors have piston / ring failures which make for bad blow by.

I have had 2 different 389 motors that had broken out the ring lands between the top and second compression ring.

If that's the case with yours then it rebuild time not only due to the broken piston, but if the motor was run even a little with Antifreeze in it then it's going to need bearings also!

I agree. I have experienced the same thing. Happens when running a 10:1 or more CR closed chamber, carboned up old engine on too low of an octane. Have seen many factory cast pistons with the lands broken out.

Update.

Lapped the valves, gasket looked to have failed. Glazed bores got a little flash rust while getting the heads done but no scoring so hopefully the pistons and rings are OK. I put a 3.75 flex hone down the bores, new blue felpro 8518PT head gaskets and will see if that solves the water-in-oil and blowby problem. Bolts torqued to 95ft lbs,, a little more (105) on center bolts.

We have a problem on getting the exhaust pushrod in on the #8 cylinder. The AC blower box is in the way!
Can't remember how I did this back in the day. Not the first time I've had heads off an early AC car.

I think I had removed the passenger motor mount bolt, and jacked up that side of the engine until it fit?
Any ideas?

Yup, jack up that side of the motor, but loosen up on the long thru bolt on the drivers side mount also., and also loosen up on the head pipe bolts in the exh manifold.

Yeah, I think the drivers side throughbolt needs to be loose also. What to use as a jacking point? The last '65 I did this to had a manual trans and I believe I jacked it on the bellhousing. This car is an automatic.

Maybe block of wood on the front of the exhaust manifold?

The amount of caked oil in the lifter valley was amazing. Got most of it out. We hot tanked the heads so those are clean.
There was a little rust on the underside sheet metal of the valley pan and valve covers, so I think this car has had a failed head gasket for a very long time, prior to me buying it.

While the valley pan is off, was thinking of flushing with gas but don't want any to remain in the pan.
I know the baked oil does little harm.

I drained the recent but blackish oil and there wasn't much water in it at all. There was moisture but it wasn't a brown mlkshake.

Forgot to mention the timing cover water outlet on this '65 engine is badly corroded, probably the worst I've seen.

Oil sludge in those earlier engines isn’t unusual. Far more paraffin was used in motor oils back then( most of the motor oil was non- detergent as well.

Am I reading that you flex-honed the bores with the pistons in place and are hoping the old rings will seal?

We all assume the cam lifters dished, camwiped, and timing chain smacking the Timing Cover. Dizzy didnt lift out huh. Just gotta be.

Once you get this all bolted up and ready to fire over I would first borrow from a friend or rent from a tool rental location a rad pressure tester and just fill the cooling system with water and confirm that it holds 16 psi.

I just needed to do a quickie to get this car movable again under its own power. Will rebuild it later. Flex hone was only used to knock off flash rust on the bores while the heads were off. I know it's not meant to be used like that, but I have no time or space to pull the engine and do a rebuild right now. I bet it will run just fine.

Cam and lifters in good shape despite the mess in there.

People worry too much about old engines. They will work enough for a driver while in amazingly loose condition. Years ago I had a 326 that had worn holes through the bottoms of the lifters. At low speeds ran rough but once you got the speed up it ran fine. One thing you need to be careful about is cleaning sludge out of the engine. You are better off in some cases leaving it there. I saw several that were "cleaned" only to find that a lot of that sludge was now caked in the oil pump pickup and no oil pressure.

Agreed. Don't know of any way to get sludge off besides scraping off or hot tank. Or letting dry out and flaking off. Will keep an eye on oil pressure and run 15w40 or thinner.

One man's " running fine" is another mans needs a rebuild!

We’ll see if the vapour blowby is gone after replacing head gaskets and timing cover.

Looking for a nice 65 timing cover BTW.