Water in this oil or not?

[Grub54891]

You might not see the crack as its inside the manifold. you can take the endcaps off and have a look, or do the acetone test, you fill the wet side with acetone and see if it leaks in to the intake side. Or I n your case since the wet side already leaks, fill the intake side and and see if it leaks to the wet side. I would do neither, as you already know it's cracked.
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[lister]

Yeah im just going to throw this intake in the trash. I may take a cutoff tool to it just to investigate.
I was just looking for a smoking gun for the cause of the water in the oil.
Im going to do a proper leakdown on the cylinders too

 

[lister]

some good news, the leak down test turned out very good.
So im pretty sure now i DONT have a cracked block, head or headgasket!

So i'll be replacing that intake manifold and all the gaskets and then.....fingers crossed!

 

[Rick Stephens]

Leakdown test won't tell you if the water jacket in the block is cracked, only if the head is cracked.

 

[lister]

What will then? Fixing everything else then running the motor and looking at the oil later?
I did a pressure test through the thermostat and it held pressure well

 

[alldodge]

Leak down test checks cylinder pressure integrity, the cooling system (block/heads) would need to be pressure tested and Bruce mentioned and easier way

 

[lister]

Well I JB welded the crack on the outside of the manifold, sealed off the exhaust and ran pressure through the thermostat and it held.
Even if theres a crack on the engine side of the manifold I would think that means the block jacket is good surely.
hurrrgh so confusing

 

[alldodge]

Thought you were getting a new manifold

 

[lister]

yeah I will be when I have the money.
Just wanted to test the head gasket this weekend which tested fine. I'll take the old one off tomorrow and hope to see some cracks on the engine side or inside when I cut it open

 

[Rick Stephens]

We are probably talking different thing when we say leak down. Normal leakdown you pressurize the cylinders through the spark plug hole to find leaky rings or valves.

 

[lister]

Yeah this ^^^ also checks head gasket and cracked head problems.
All I found was a tiny leak in the valve cover gasket

 

[bruceb58]

You need to pressurize the water jacket. Testing the cylinder with a leak down does nothing for the problem you have.

 

[lister]

Isnt that what Bondo's tip was for?

Ayuh,.... It ain't the compression that seems to be the problem,....

It's the block's coolin' passages,....

Isolate the block, from the rest of the plumbin', 'n pressurize it to 'bout 15 psi, 'n Listen,....

It oughta hold the pressure, if it don't, follow the hissin' sounds to the cracks,....

Which I did and it was fine, held pressure well

 

[alldodge]

In your previous post you were mentioning the leak down test and using the spark plug holes, that is the cooling system. So if you did pressurize the cooling system and there was no air leak then guess you don't have a leak

 

[rderenzy]

how did you find out your oil was this color anyway?
did you not change the oil prior to winter and you were just now changing the oil?
or did you just want to check, had a feeling and extracted some from the dipstick?

Any chance this was cracked all of last year? even if you did not remove all the water, but you still ran antifreeze into the engine(a good 5 gallons) there shouldn't have been any freezing issues....right?

 

[lister]

Yeah you know I've had a feeling of the same too, maybe the exhaust manifold was just cracked towards the end of last season.
I've had a funny feeling that I checked the oil before ever starting the engine this year and noticed it had water in it. So you may well agree with my suspicions.
I noticed the oil was a funny color through the dipstick then emptied it all out of the drain plug to produce the pictures in the first post of this 6 pager.


At the end of last season, I ran water through it, then 2 gallons of antifreeze until it stopped coming out of the exit hole on the outdrive for a few seconds.
I appreciate your help everyone, im going to call it good and cross my fingers. Worse case I can sell the manifold im going to buy so im only out the cost of the gaskets if it turns out it really is no good.

 

[rderenzy]

gotcha...so you emptied the oil. I was just curious.
2 gallons seems a little low...I thought mine took close to 5.
4.3L merc
good luck

 

[Grub54891]

At the end of last season, I ran water through it, then 2 gallons of antifreeze until it stopped coming out of the exit hole on the outdrive for a few seconds.

Did you drain the block of water before the anti freeze went in? If not you have more than likely broke the block.

 

[bruceb58]

Did you drain the block of water before the anti freeze went in? If not you have more than likely broke the block.

More people crack their block with this method than any other.

 

[lister]

No Title

Took the manifold off, no obvious cracks that I was hoping for. Also noticed the freeze plug slightly pushed out on the block.
Could be the manifold is cracked on the inside I suppose, second pic shows one of the holes pretty gunky and brown like the water jacket