346 water in the oil and cylinders?? Again! (Still) Another development!!

[gary griffin]

Another development  4/3/18

  Now I find that water is being sucked from the cooling system into the intake manifold.  In the center of the block on both sides of the valley three are two  outlets feeding into the intake  manifold probably to pull out moisture from the center of the block.  Apparently there is a leak in the block and the vacuum caused by the carburetor is now bringing large amounts of water out of the water jacket into  the intake manifold and into the cylinders. I have a head off but when I cranked it with heads on there was a drop in  cylinder pressure of about 50 percent so I suspect I have bent rods for those cylinders as it was cranking against two cylinders full of water.

Time to look for a new block or a good 346 engine!!


Below here is an older posts!!
More about the perplexing failure of my engine. I have been chasing the water leak in the garage and on this site for a long time. Working with a rebuilt engine and have never figured out how large quantities of water get in the oil. History! I am retired and have other cars and hobbies so this is a long running problem that I do not invest enough time in. Getting serious now. Following is short version of the story!

I noticed a pin hole the in the water crossover from right bank to left bank. New soft plug was installed in the shop??

Engine ran fine but did not run it very long.

Car sat a couple of years and  I started it with minimum water and it ran fine but as I added water it soon started coming out of the exhaust.  Replaced head gaskets  and ran same way. Large amounts of water quickly in the oil and in the exhaust.

This morning I hooked up a compressor and jury rigged an adapter to put air in the radiator.  At 5 PSI at the regulator there is good flow but
no air exit points in the engine compartment  have been detected but there is air discharge in the tail pipe so there is clear opening from coolant side to exhaust !!  I did not have an adapter for the small spark plug holes so I did a compression check with old worn rubber tapered tip. Compression seems to be equal in all cylinders.  Water discharged from a few of them probably got in when head was removed?  I have put WD-40 in all cylinders as it is heaver than water and will go to the low spots and protect the rings and cylinders to some extent.

I suspected the replaced soft plug in the coolant crossover was part of the problem but it is separated form the galley by sheet metal cover and a gasket. Is the gasket good enough to stop pressurized water flow??

There are picture of the inside of my engine in my restoration blog page 2. If you look you will see the pin hole in the soft plug in the crossover before it was replaced,

ANY IDEAS???

[Steve Passmore]

I suspected the replaced soft plug in the coolant crossover was part of the problem but it is separated form the galley by sheet metal cover and a gasket. Is the gasket good enough to stop pressurized water flow?,

ANY IDEAS???

I don't fully understand this part of your thread Gary  What do you mean when you say the core plug is separated from the Galley by a sheet metal cover and gasket? We are talking about a flathead, aren't we? Nothing covers the core plugs over the water crossover gallery.  Not that this has anything to do with water in the oil, unless there's a flaw in the cast iron base of that gallery?

[Bobby B]

I don't fully understand this part of your thread Gary 

Gary,
Hi. I agree with Steve...It's not making sense. Are you referring to the 2 valley covers under the manifold where the tappet blocks are hiding? Are you referring to the Crossover cast into the block with the 2 small core plugs? That's the ONLY spot that water should be in. You need to do a real compression check/ leak down test with the proper tools, or pressurize the cooling system with the correct tool. Please Post a picture and point to your suspected trouble spot.
                                                                                                                        Bobby

[gary griffin]

You are both right.  There are two covers in the valley. The perplexity is how water is getting into the oil when it gets over a certain level, yet when ran with low water level no water gets in the oil or cylinders.

I have new knees as well as back issues and therefore I do not work under the hood myself but have a fairly good mechanic working for me part time. He is young and not familiar with flatheads. 

I will do more air testing trying to eliminate possibilities,  Next will be to remove heads I guess? The compressed air going from the radiator to the exhaust has me puzzled too.

[Bobby B]

Gary,
Hi...Was the block magna-fluxed? Sonic tested before boring? Are you sure there isn't a hairline crack (block, cylinder wall) that rears it's ugly head once warmed up and pressurized? You need a leak-down/ compression test. If you want to do a cheap quick test, go to your local NAPA and get this kit. Immediate results. But I think you already know that you have a problem, it's just locating it. It's got to be something that was overlooked during the rebuild. We all know the issues with these blocks....Good Luck!
                                    Bobby

[Fred Pennington 25635]

Car sat a couple of years and  I started it with minimum water and it ran fine but as I added water it soon started coming out of the exhaust.  Replaced head gaskets  and ran same way. Large amounts of water quickly in the oil and in the exhaust.

This morning I hooked up a compressor and jury rigged an adapter to put air in the radiator.  At 5 PSI at the regulator there is good flow but
no air exit points in the engine compartment  have been detected but there is air discharge in the tail pipe so there is clear opening from coolant side to exhaust !!

Gary, I believe this says it all. The bad news is I think you have a cracked or rusted through block in one or more exhaust ports.
I would suspect the 4 in the middle ( two on each side). The crack or perforation could be around a guide. if the valve guides were improperly installed that could cause a crack. If the metal was deteriorate then the guide installation could have pushed it over the edge. This area is know for cracks around the valve seats. It is not a stretch to include the port.

You might be able to test it by pressurizing the cooling system and with the spark plugs removed listen for the air leak.
One cylinder at a time you will need to jog the motor around to get the exhaust valve open, then listen for the air leak.

If the heads are off just listen for air leaking with the valve open.


Good Luck
 

[gary griffin]

I have since removed the heads and pressurized the oil pan with vacuum cleaner exhaust and saw no bubbling in the water jacket.   

Engine running on low water nothing but when water is added a large amount of steam and moisture coming out the exhaust.

I do not know if there is a way for water to get from the valley into the oil pan??  I know that a soft plug in the water crossover was faulty and was replaced. Could it have failed and the valley is flooded? If not it almost has to be in the heads. I took them to a good machine shop who does test them but the head is too wide to work in his equipment.

Water gets into the oil, not the opposite, no oil in the water!!

[Jeff Rosansky CLC #28373]

I dont know much about your engine but had some thoughts on something to try.
Jack the car up to where you normally would for an oil change. Then let it sit overnite. Come out in the morning and just crack the drain plug and see what comes out.
If it's oil then there is no water in the oil so your problem happens in such a way that the oil doesn't become contaminated. If it is water then you can drain it to where oil comes out, run it and try it again.
This is not an answer but it may help you diagnose where the water is coming from.
You could also disconnect (easier said, I know) the exhaust crossover or Y pipe to see which side is blowing the white smoke. Then if you want to dive in more then swap the heads and see if it follows the head or stays with the block.
I have been watching this thread and wish you luck--both in finding the problem and then the fix.
Jeff

[C Gorgas]

I think that is an interesting problem that can be resolved by magnafluxing  the block big job of course. I had a '41 and the block cracked due to lack of antifreeze. I went to the pharmacy and bought a quart of eising glass often referred to as rising glass poured in the radiator and solved my problem. I drove the car for about 4 years with no further difficulty. It never missed a lick. Chet 445

[bernie schweiger]

I hade had a problem with the head bolt threads being dirty which causes the torque of the head to be low. I always clean the threads with a thread chaser before installing the head to make sure you have proper torque on the cylinder head. I believe the rated torque is low for a cylinder head so a  little loss is substantial.

On my Lasalle (322 engine) I was able to remove the pan and see the water leaking out of a crack on the inside of the block. Had to get it welded.

Bernie