[I]Getting water in oil on new rebuild. Dropped pan to discover water running in between number 4 #5 cylinder(the front 2 on the drivers side). from a whole in the block. Don't know if hole should be there or something has knocked a hole.

Where does the whole go? water is running out of whole, not dripping. Can anyone tell me where that hole goes?.

Any help is appreciated

 

Howdy,

It's really hard to tell unless you reveal what engine this is. Some V-8's have holes in the "valley" for oil to run back into the crankcase.....

If it's a small block chev, and the block is cracked (from freeze damage) they frequently crack in the valley right above the lifters on the cylinder (was this engine previously in a boat?)

If you have a leaking intake manifold (cracked, etc) or gasket leak it could allow coolant to get into that valley which could put it into the crankcase.

Regardless of what engine this is, the best way to find hidden cooling system leaks is to pressurize the entire cooling system to 15-20 psi using compressed air.

Disconnect the radiator, heater core and close off all the cooling system connections. Then connect an air hose, via a valve and gage. You can make all these connections and close open open holes using simple plumbing stuff from Home Depot.

Pressurize to 15-20 psi and close the valve.

After your compressor shuts down, it'll be easy to hear any leaks. Do this with the heads, intake manifold, water pump installed.

For external leaks, you can spray a solution of dish-soap and look for bubbles to locate and identify any cracks.

For internal cracks (with the pan off) you could do the same thing once you hear the hiss of air escaping if it's not obvious.

Cheers,


Rick

 

It is a 8RT Flat head V8 Ford 1952 model

 

NO on pressuring the whole system to anything more than 4 psi, unless you want to blow the tanks off the radiator! It's leaking now with no pressure, if he pulls the intake manifold it will be obvious where the leak is.

 

Yes I read that and knew not to pressurize over 5 pounds. I found the problem with water in oil. I removed the intake manifold and found a crack behind # 1 cylinder valve springs in the block right at the top of the cavity where the valve guides come through the block.

I guess I will have to find another block. Can't get the machine shop to call me back. Wondering if I find a 8BA block, how many of the parts will work on the 8RT or is there a difference?

 

Sorry to hear it. Was the engine stuck when you took it to the machine shop? In other words, did they have to pound any valves/lifters out due to rust?

No real difference between 8BA and 8RT; truck engines had a slightly different cam, heads with lower compression ratio, but all parts interchange.

 

You may have missed that I said to disconnect the radiator and heater core.

We're only talking about pressurizing the block and heads here.

If you remove the intake manifold on most V-8s, it will usually be impossible to pressurize the cooling system since coolant flows in the manifold (don't know if this is true in a flat-head) If you wanted to make that work, you would have to bolt blocking plates to the heads to cover the coolant ports for the intake manifold

Since the engine type wasn't indicated, I was speaking generically.

One NEVER pressurizes any cooling system with a radiator (or heat exchanger) connected.


Sorry to hear the block is cracked. I wonder if someone left it over a winter with plain water in it at one time.....

 

There were some valves stuck open but the engine turned over. Do u think the machine shop could have cracked the block while dissembling the engine?

 

HT32, Sorry, I did miss that about disconnecting the radiator. Flatheads don't have any water connections to the intake, and each bank is a separate cooling system, only connected to the other at the radiator. With 6 connections to plug (two inlets, two outlets, plus 2 heater), it's easier to just pressurize at the radiator cap.

It's possible, but not real likely the shop did this. As HT32 says, likely a freeze crack. I was wondering if the lifters in that area were rusted by previous leaking.

Did you ever run the engine, before the rebuild? Sometimes cracks in running engines will be plugged by mud and rust, only to be opened up by hot tanking and flushing. Can you post a picture of the crack?

 

Ross, No Problem! I just learned something about a flathead!

I think it's unlikely a reputable machine shop would crack a block and not know it (and then not tell you ) (not sure how they could do it unless that block was sleeved and they cracked it that way....

It is possible to get a block welded and there are shops that do that......but it is fairly expensive to do it right though. It might be worth it to fix a big diesel, but it may be more cost effective to just find another block.

I know a guy in Seattle that rebuilds flatheads. Next time I speak to him, I'll ask him if he knows of a source

Sorry about that,


Rick

 

Really? Maybe I misunderstand you but then what is this tool for?

 

Howdy Pete, actually you're right!............ Never say Never.......I should have qualified that statement I suppose........ When checking an engine block cooling system for cracks, I would not pressurize it with the radiator (heat exchanger) and/or heater core connected (because I would want to see if the engine block(& heads) would hold pressure)

If I was going to pressurize the radiator to check it for leaks and I knew the block wasn't cracked, I would use something similar to your device above.

Cracked blocks are very common around Spring time in marine engines. (people frequently either don't drain them for winter or they don't drain them properly.)

One of the best ways to find the cracks (if they're not obvious) is to pressurize the block to about 15-20 psi and spray some soapy water on the outside and look for bubbles. If it's on the inside, you can usually hear it when putting your ear to the oil fill.

If I suspected a cracked block, I would still disconnect the radiator and pressurize only the block and heads (and for the reasons indicated above, you probably shouldn't pressurize any of the older rads to that kind of pressure,.........although the guy that rebuilt my OEM radiator for my 55 F-600 told me I could probably get away with a 13psi cap)

Obviously, the newer radiators are ok with higher pressures. ( My 2005 F350 has a 16 psi cap)

 

Well IMHO that tester is a good place to start. Pretty much standard practice in the auto industry as the radiator is most often the source of the leak. Obviously not in marine.

I'm somewhat familiar with marine engines. I had one of the last Super Novas built by Nova Marine before they sold to Wellcraft. It had a 440 6-pack with Speedmaster outdrive and big Kiekhaefer hydraulic trim tabs. It was a real beast until the heads cracked from heat due to rubber water pump impeller loosing all its vanes. "The happiest day in a boat owner's life is the day that he buys it and the day that he sells it". . . well maybe not entirely true. At high speed it was a real thrill ride for the guy driving it. Terrifying for those riding as the deep V hull skimmed across the top of waves.

 

AKA "Chine-Walking"? Very scary!! I have experienced it in my 87 Four Winns Liberator crossing a wave at an oblique angle only going about 60mph!

( powered by a 1997 7.4L Mercruiser powered Bravo III)