Cracked block

"I have a 165hp inline mercrui

"I have a 165hp inline mercruiser. It start fine but after 30 seconds of running, water mixed with oil is coming out the hose from the valve cover. I checked the oil gauge and it appears to be kind of milky. I removed the 6 sparks plugs and start the motor. It seems to be fumes or spray coming out from the cylinder no. 1. So my question is, is it cracked at the manifold (which I hope) or is cracked from the engin block? Thank you."

Got to pull manifold and head

Got to pull manifold and head to check.I`ve had them start leaking into the bore right behind the circ pump .

"Most likely its a gasket fail

"Most likely its a gasket failure, which is a good thing for you. Well, good compared to a cracked block of course. Like Bt says, got to pull the motor. The 165's are known for water getting into the 1st cylinder due to gasket failure."

"I thank you so much for this

"I thank you so much for this quick reply. I made a mistake. After I looked in the mercruiser repair manual, I realised that the problem is in cylinder no. 6 instead of no.1. Is it still a gasket or else? Thank you."

"ok then, pull the riser and c

"ok then, pull the riser and check for water in the manifold.riser may have a hole allowing water to drop into #6 exaust valve and into the engine."

Hi there. Took me awhile to r

Hi there. Took me awhile to respond on this. Thank you very much for your help. It is the manifold indeed. I realised that I forgot to open the flush valve on the manifold. So I guest it frose during winter. Better this than the block though.

"Hi there, I recently purchase

"Hi there, I recently purchased a 1982 Webbcraft. The boat is in immaculant shape, and the previous owner disscussed all the maintenance that had been accomplished. He started it and it sounded great, and ran nice and smooth. The first trip to the lake, not even off the trailer and there is water in the oil. I ran a compression test, and have 120 psi in each of the 8 cylinders. When I took the breather cover off, I noticed that the hose from the breather to the valve cover was off. I had previously washed the boat with the rear cushions off, could this have got water in it enough to cause this, or could condensation over the winter have caused this, and what should my next troubleshooting proceedure be."

"One more thing. The previous

"One more thing. The previous owner told me that a marina at Lake Tenkiller had winterized the boat. According to him it was pickled (I have not contacted the marine; therefore, I have no proof of that other than his word)."

"Todd:

Change the oil &am

"Todd:

Change the oil & filter ASAP. How much water? Water vapor is a byproduct of combustion and can accumulate if the engine does not run at operating temp. Is it running at oper. temp?

Did you wash the engine? That would knock off the hose and a small amount of water would get into the engine.

Was there water in w/the spark plugs?

Check the oil level and record for reference. Now run it on ear muffs w/plenty of water pressure for 20-30 mins. Stop after 10 mins. and let it sit for 5 mins.

Now check the oil level. If it increased, there is water getting in the block. Pull the plugs and look for water.

None there? Block is the problem.

If water IS there then the exhaust mans. or risers are the likely source.

No water at all; continue to run the engine to dry out the moisture in the engine."

"Hi Guy,
I couldn't tell

"Hi Guy,
I couldn't tell exactly how much water was in it, I believe that the oil became aireated and was about 3 inches up on the dip stick. I didn't wash the engine, but I was washing years of dirt off the engine deck, this could have possibly got water in the open breather port. I am not sure if it was water on the plugs or not, they were wet though. That was after sitting for a day. One last thing, I am having trouble getting the oil out using a pump, any other suggestions? Thanks"

"Three inches up on the D'

"Three inches up on the D'stick is alot of water! The oil doesn't want to pump because it is cold and thick. Put a quart of GUNK engine cleaner in the oil, put a scratch on the D'stick to mark the level and (I hate to say it) run it at idle 3-5 minutes on muffs. WAIT 5 mins. and measure the fluid level on the D'stick and compare w/the last level. If it went up in fluid you have a serious issue that needs fixed right away. Then pump it out.

If it idles smoothly and you still get more water in it then it is most likely a block issue.

Pressurize the cooling system to check the block and heads. Pinch the water inlet hose with a needle nose vice grips. Connect a skinny bicycle tire tube w/valve between the two exhaust man. hose connections at the T'stat and connect the other two riser outlets at the T'stat together w/1 of the hoses to form a closed loop for testing. Pump in 10 - 15 pounds of air measured w/a tire gauge and wait 30 mins. and recheck the pressure. Check all hose fittings w/sopay water for air leaks while waiting. If you have a screw on gauge it is easier to see if you loose pressure. Listen inside the carb for a hiss or gurgle; do the same for the exhaust risers where hoses are removed."