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M360 Flooded with Water - What next?

Resorter_Dude

Resorter_Dude

New member
I F'ed up. Ran my newly rebuilt M360 in my driveway. Not bad in and of itself, although the driveway is a steep down slope, so water from the exhaust flooded back into the cylinders.

Next, I made attempts to dry it out, added some Mystery Oil to each cylinder.
Removed, tested and replaced the Exhaust manifolds.
Removed all plugs and turned her over several times.

Replaced plugs and tried to start.
Now it won't turn over. Tried to go, moves a small amount, and stops. Like it is full of water again. Even tried it without the hose running, same thing.

Troubleshooting in the dark.
Compression test?
How many things, and what, could I have busted?

Thanks for any help.

RD
 
Sounds like the manifolds or risers are shot, letting water leak into the cylinders at shut down. First remove plugs, disconnect the coil, then turn the engine over to dry out the cylinders, hopefully it didnt sit too long rusting the walls and rings. before putting the old manifolds back do a pressure test on them to make sure they are not rotted out on the inside. Or you could block off one end, pour some colored water in the open end and see if any is leaking into the exhaust ports, also look for rust inside the exhaust ports, that would tell you if you got a leak there. P.S, dont run engine without water flowing to it, you'll burn up your raw water intake pump.
 
Is a few drips a deadly leak? I pressure tested them before they went back on... The system is not under pressure, it's raw water cooled...
 
You're flirting with disaster if you try to keep starting it with water in the cylinders. I'd pull the manifolds and pressure test them. All you need is to fabricate a 1/4 " steel blockoff plate for the other end, fill it with water, and put 15 pounds air pressure on it. If it leaks, toss it out; if not, you might have head gasket issues.

Jeff
 
Sorry if I missed it but did you check the oil to make sure there’s no water in there?

If the oil is good, I’d repeat the process of pulling the plugs and turning over the motor.

I know it’s a rudimentary suggestion but, check your battery as well…….it may be worn down from these exercises and lacking the juice to turn the motor.

I’m not suggesting that you run it off the hose but, I would keep the hose off of it until you’ve narrowed down the problem (at least having ruled out that manifolds….again).
 
OK Manifolds passed the pressure test.

Took the plugs out, turned it over small amount of water can out...otherwise seemed fine.

Tested with two different batteries and two starters, won't turn over.
Turns 1/4 turn or 1/2 turn and stops again...

UGH
 
So you just rebuild it ,it ran for a while then it got stiff and it got water in the cylinders sounds like what happened to my parts motor

which head gasket did you use,what kind?

I noticed this guy used copper coat on the head gasket

is that customary?
 
If you have water in the oil, and you're sure the manifolds are good, then check out the head gaskets, might be blown or the wrong ones. You should be able to turn over the motor by hand with a large socket wrentch on the crank pulley bolt.. If you cant,, then it might have rusted in the cylinders siezing it up.
 
Thanks for all the detailed comments...

I finally got her un-hydro locked. I had to drain the block and remove a hose from the water pump to get water to stop coming out of pistons 1 and 2. Now it will turn over with compression (which by the way checked out about 125 psi per cylinder)

Next question is weather to try to start it or see if water makes its way into the cylinders from simple water pressure in the to the cooling system?

Thanks again.
Michael
 
You can hook up a hose to the intake, and see if any water gets in there. If it does and you're 100% that the manifolds are good, then I would suspect the heads might have rotted out inside, especially if you're in salt water. Happened to me on a mercruiser I had, the cylinder head rotted out from the salt water cooling, letting water get into the cylinders. That would also explain the water in the oil thing
 
Michael - did the shop that rebuilt the long block put the intake manifold on? If not properly sealed, this can be a culprit.

If your manifolds are good and all of the plumbing is correct, the ingestion may be more than the angle of your driveway......as you'd originally suspected.
 
Still filling with water. I turned it over thinking I would start it and get it up to temp to dry everything out. Filled up fast and I could tell the starter was laboring. Plugs out and sure enough more water in the cylinders, mostly #7.

Next plan is to dry it our again, and see if I can fill it up without the manifolds connected...

Oh and to remove the valve cover and see if they are moving correctly.

Bummed Out Resorter Dude.
 
Like I said before, your cylinder heads may be rotted out letting water into the cylinders, take off the manifolds, connect the hose, and see if you get water out of the exhaust ports, if you do there's the problem.
 
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