Thread: 426 Hemi Oil In Water

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I recently Purchased a 66 Dodge with a 426 Hemi that was left out in the cold with not enough antifreeze in it. the unit runs and goes and doesnt overheat but gets oil in the water. What would be the most likely way to preserve this motor and how and where should i look for the possible crack. Any tips would be greatly appreciated. Email gymbotwo@verizon.net

V8's often crack in the valley, above the lifters. Usually not worth fixing, but a 426 is worth the nickel. A hemi head has a large flat top surface, flat places are the first to bust. The sides of the block usually crack on the outside and don't cause internal leaks.
Are you sure it froze up? A leaking head gasket can also cause oil in the rad. Does it get coolant in the oil? If not, it's probably an oil passage that's cracked, that can be a bitch to find, let alone fix.

Gymbo; I would tear that thing down and take a real good look at it.
I don't know how old that motor is not only that If there was no Anti-
Freez in it. The head head gasget could be gone too.
That's where I would look first before thinking the worst.
It's just like Pope said but I would give it a good looking at.
I used to play with the big block dodges back in the day,
but they started getting to expensive for me.
If the block is cracked I wouldn't even mess with it.
Save what you can and toss the block.
We had several 426 hemi's that we tried to have
fixed or welded and all of them would just crack again.
Kurt

i diddnt think a head gasket could cause oil in the water. how could it? is there oil galleries in the head? i thhought the oil went up top via push rods. i dont have much experience in hemis so please forgive me. i will look at the head gaskets.
Thanks,
Gym

While you will need to look at ever possiblity, I wouldn't think your problem is caused by a head gasket. There also are more ways other than welding to fix a cracked block. If that is the problem.

With the price of orginal Hemi cars going through the roof, and if this is the orginal Hemi block the last thing in the world you want to do is throw it away. Any number matching Hemi, that is all numbers orginal to the car, is worth 10's of thousands more with the correct block.

The first thing is to determine were the problem is. Then and only then can you make a choice on __How to TRY and fix it. Welding is one way but it is only one way. Good luck!!

Roland

Hombre; He could just fill the block if he ain't gonna drive it on the street.
But if he tries, and it comes apart again he may not save anything from the motor.
I have had lots of experience with big block dodges, though it has been a few years ago.
I'm just trying to save the guy some money. Kurt

There is an oil passage that takes oil to the rockers. I doubt that's what's causing the problem, but it's just possible.
If it runs well, you could try waterglass in the rad. Flathead Jack sells it for cracked Flatties. I have used it with good results on freeze-cracked engines, though nothing high performance. It might not hold up to the stresses a Hemi could put on it.

Kurt, I understand with what you are saying, and usually would agree, but this is an orginal Hemi car from 1966. It then becomes a whole new ball game because of the worth of those number matching Mopar's. The internals of the engine are easily replaced and at no disadvantage. The block however is the verifible part of this equation. If and that may be a very big "IF" it can be saved it should be simply because it add's so much value to the car.

I know severeal folks with original Hemi cars, a couple of Chargers and a Road Runner or two. I personaly have a Hemi Cuda. Some of these folks and I include myself in that some, like to drive our cars. The number matching engine means so much as to value of these cars that some folks pull out the orginal Hemi and replace it with a Mopar Performance 426 to do that driving, store the orginal Hemi until they decide to sell. Seems like a lot of trouble but when you are talking about a motor worth as a number's matching engine for a Hemi Charger you are talking $25,000 to $75,000 dollars worth of value just in the motor alone. Yea you need to save one if you can.

Roland

Originally Posted by vara4

If the block is cracked I wouldn't even mess with it.
Save what you can and toss the block.

Kurt, you can't be serious, toss a Hemi block??? I agree with Roland 110%, especially if this is a numbers matching engine block, only a fool would toss it. If it isn't cracked in a 'load bearing' place, it can be usually be saved. I used to own and race numerous Hemi cars in my younger days, I've seen Hemi blocks with holes punched in the side from broken rods that have been repaired and used again.

Gymbo, the first thing you've got to do is disassemble the engine carefully to locate the source of the leak. If necessary, have the oil passages pressure checked to locate the leak. If this is a numbers matching block, take Roland's advice, do whatever it takes to save it.

JMO,
MIke

Well believe it Mike,
Because I didn’t hear him say that the numbers were matching.
And I have done it with hemi’s that were not matching.
And I agree with Hombre on that, Sure if they match stick it on the side.
But You can bet if you had a block with a hole in the side from a rod, that thing
will crack or break again in that same spot.
I know because I’ve tried to save plenty of them, I might add with on luck.
And I spent tons of money trying too.
All the guy’s that I ran around with in Las Vegas will tell you I was known for BIG BLOCK
Dodges. I walk in to work early and I hear the boss call me on the pa intercom system.
I ask him how he knew I was there when I was an hour early.
He told me when I pulled up in my Charger I would shake all the windows in the front of the Hacienda Casino.
And I’ll just leave it at that. Kurt

the block could be fixed if you know what your doing i would say it would have to be looked at some iron welds better then others. the block could be welded with iron filler rod or nickel rod if not all busted up .i have fixed very hi out put bbc engines with nickel rod .you can look at my photos to see what can be fixed .if you can buy new then do so. but iron blocks get fixed every day just like any thing it is fixed not new

Thanks Guys! FYI, it is a numbers matching 66 Coronet with a 4 Speed ragtop. There is no water in the oil only oil in the coolant water. So im guessing its leaking somwhere where the oil and water come in close proximity and due to the higher oil psi the oil migrates in that direction. if the water psi was higher than the oil psi i guess i would have water in the oil. is there anwhere that i can get some diagrams of where the oil galleries are?
Tanx,
Gym

If you want to do it right you're going to have to strip it to the bare block and pressure test the oil passages. Lots of tedious work, but nothing you can't do in a home shop with some dedication and ingenuity. Or take it to a good engine man to have it done. My guess would be a crack in the valley, intersecting a fore-and-aft oil galley.

Here is a site that saves us diesel guys occasionally. The Dodge guys with the infamous '53 bock all have this place bookmarked. It really does work. I don't know the physics of it but Cummins will use it on occasion so it has to be good.

http://www.locknstitch.com/