Water in cylinders. Yikes!!!

[Howard Sterndrive]

Re: Water in cylinders. Yikes!!!

I connected a water hose to the the incoming hose line from the outdrive to the thermastat housing. This pressuzied all of the motor water passages

and water was pouring out the exhaust during this test? or you had the water lines to the exhaust manifolds blocked off?

if the former, then nothing was pressurized.
If the latter, then the manifolds sure aren't the issue.

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

All water lines were attached as designed. All I did was diconnect the water hose from the outdrive to the thermastat and I installed a connector to that line to pressurize the entire cooling system.

 

[Howard Sterndrive]

Re: Water in cylinders. Yikes!!!

then there's nothing pressurized.... the water would be pouring out the propeller and idle reliefs. 0 psi.
pressure only exists when there is restriction to flow, and when it can freely dump out on the ground, there is no restriction
boat cooling systems like yours are not pressurized.


regardless, it sure sounds like you need new manifolds.

Take them off and look in the exhaust ports. After that test you'll probably find rust and water in the exhaust ports and maybe even see the cracks or holes in them by eye.

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

I'm already in the process of pulling them. I'll be back.

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

Here is what i found on the exhaust manifolds.
Left side where most of the water was coming out of the spark plug holes. Slight rust stains in manifold where it bolts to the motor. Drain hole completely plugged with drain device removed. Opening at the top of the manifold severely corroded and falling apart. Hard to see water ports due to the corrosion. Right side. No rust in the manifold openings on either end. Drain hole completely plugged with drain device removed. I have an inspection camera but it is very difficult to see any internal damage. Any ideas???

 

[Reinell-BRXL-191]

Re: Water in cylinders. Yikes!!!

do the test again that got water in to the cylinders as you were rotating it... then open up the carb and take your inspection camera and make sure water is not entering the plenum - yes.. we are back to the intake manifold... I find it very hard to believe that both sides of the engine had the exact same failure at the same time allowing water in to both sides of the heads... sounds to me like it has a central source that both are getting water from.. and the only source would be the intake..

more water in one side vs. the other could be the angle the boat is leaning on the trailer.. you should be able to eyeball that and determine if the side with more water is listing to that side..

You may want to block off the hoses going to the exhaust manifolds.. that will actually pressurize the engine

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

I did block off the hoses that go to the exhaust manifolds and turned the water on again. The cylinders stayed dry with the water pressurizing the motor and cooling system for the 45 minutes I tested it. For my next test I'm going to hook a water hose up to the supply side of the exhaust manifold and check the water flow though it. I'm surmizing that the exhault manifolds might be plugged up with rust and rot that it is creating back pressure within the exhaust mainfold allowing water into the cylinder head. I'll update later.

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

I ran the monifold trest as mentioned above. Through an assortment of fittings i connected a garden dose to the supply side of teh exhaust manifolds. I stood the manifolds up to simulate how there mounted on the engine. When i turned on the water the right one did not have any water coming into the exhaust ports. However the left side had a a wterfall coming out from the two back exhaust ports. The left is definately trash after this test.

I know the bat wing manifolds are no longer made. I will have to by a new exhaust manifold so do I have to buy two new ones or can i buy one of the new styles and use my existing good manifold. Besides looking crazy would there be any other considerations to account for?

 

[Reinell-BRXL-191]

Re: Water in cylinders. Yikes!!!

Well, I can't speak to the differences in the marine applications, but on the automotive side, running 2 different manifold is a no-no - they all have different flow characteristics, and back pressures... which in turn creates differences in the combustion process.. whether or not it would cause any noticeable differences in the way the engine ran, is impossible to tell . My concerns would be if one manifold is junk, the other wouldn't be far behind.. plus, it is probably just as full of gunk as the broken one.. which would cause differences in it's ability to cool the exhaust tract for that side.. my vote would be to replace them both - because water will take the path of least resistance..

I would check ebay.. you can get manifolds used and new from 100-350 - the conversion will run you about 600-700 - so depends on your pockets.. but glad you found the problem.. ( still scratching my head on how the water is getting in the other side of the motor if only one manifold is bad )

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

Thanks for the input Reinell. I will definately replace both of the manifolds. I'm also perplexed on the water in the opposite cylinder bank. I did pressure test the motors colling system as mentioned above without the exhaust manifolds. I ran the test for 45 minutes and there wasn't a trace of water. I also didnt see any water leaking when looking through the holes in the cylinder head or through the carborater. I also checked the oil level before and after the test and there was no increase in it's level. I don't know seams weird. we'll see what happens after I replace the exhaust manifolds. Thanks again for everyones input.

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

I had one last thought. When I tested the motor cooling system as mentioned earlier. The thermostat was still in. Would that restrict water pressurizing the block? Should the thermostat have been removed for water to flow through all of the passages? As a reminder the exhaust manifolds were removed and a garden hose was installed on the supply side of the thermostat housing. The test was done without the motor running for obvious reasons.

 

[Reinell-BRXL-191]

Re: Water in cylinders. Yikes!!!

The thermostat would remain closed - whether or not any leak by would allow enough pressure to facilitate your test, I don't know... maybe not.. plus, you have to factor in the ability of a crack to open up wider when the water is hot vs. cold... But for sure you know the manifolds are suspect, and possibly the one not leaking in your test, does leak when hot...

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

Another question. I know I have to replace the exhaust manifolds. Unfortunately I cant find any good used manifolds I cant afford new ones right now. I would like to run the motor just to make sure there are not any other issues like bad head gasket or an undiagnosed intake manifold crack. So can I run the motor without the exhaust manifolds? I know it's not a real good thing to do but I just want to make there are no other issues before I buy the exhaust manifolds. In theory all I would need to do is extend the water lines that go to the exhaust manifolds and run them into the exhaust that runs through the outdrive. Any advice?

 

[Bratcher4079]

Re: Water in cylinders. Yikes!!!

Does anyone have any thoughts on how I can run my motor to ensure I dont ahve any other motor issues without the exhaust manifolds. Can I leave the manifolds off and extend the water hoses from the thermostat and place them in the exhaust Y. I know this isn't the best way to do things but I want to check for any motor issues so I can repair everything at the same time.

 

[Toypirate]

Re: Water in cylinders. Yikes!!!

I would not run without the manifolds in place as this could be a easy fire hazzard, any oil/fuel or even battery vapors could quickly become out of control in an engine bilge. verify the prssure test again with air pressure (drain the block of water as water can causes swelling of particals that can seal small leaks) with the ability to shut off the incomming air and hold the pressure in the engine (manifolds bypassed as you have been doing) the engine should hold it for hours without any loss in pressure. OR- pull the engine and run iton a stand in the driveway, borrow a couple of manifolds (tough one there) or you may just have to get the replacment manifolds for further diagnose.