water in cylinders

[docholt]

Have 1987 omc cobra 4.3l. Engine just replaced with upgrade 220 HP crate engine. 4.5 hours into running lost power began to run rough. Was able to idle back to ramp. Port ex haust header was dripping water. Pulled plugs on that side found water in 2 cylinders. No water contamination found in oil. Could it just be water jacket cracked in header, or bigger problems, look elsewhere. The dealer that installed engine is out of business, so I am attempting to trouble shoot this myself. Any and all help appreciated.

 

[Alpheus]

Re: water in cylinders

Did you replace the exhaust manifolds and risers as well???

 

[docholt]

Re: water in cylinders

no, they are off old engine

 

[a70eliminator]

Re: water in cylinders

If the two cylinders with water are side by side a head gasket, if a cracked exhaust manifold I think water would get into all three cylinders. Do a compression check and you'll know if it's a head gasket.

 

[docholt]

Re: water in cylinders

will check compressions. There may have been water in back cylinder, everything was wet. The front 2 were full. if the exhaust manifold is cracked internally would the exhaust valves allow water to be sucked into the cylinders? The exhaust manifold is definitly cracked and leaking near the exhaust gasket, may be also leaking internally, suspect it is. If compressions good then head gasket should be good? correct assumption. Where should I look for new header for port side? Thank you for you help

 

[dubs283]

Re: water in cylinders

new exhuast manifold for that thing??

may be tough to find in good condition, OMC sterndrive division went out of business in 1993 so no luck on new OEM parts

some marine engine suppliers do make parts for those packages

best bet is to try local authorized mercruiser/volvo sterdrive reapair shops and dealers

even though they may not sell that stuff they may have some ideas on good leads for ya or even be able to look through catalogs of their suppliers for that - sierra comes to mind, possibly marysville?? won't come cheap though

edit:
just did a quick check here, OMC I/O Parts - Cooling System/Exhuast Manifiolds

nothing available for the 4.3 V-6, only V-8 parts, and the numbers are sierra

 

[dhfarmboy1066]

Re: water in cylinders

Could it be the flaps in the exhaust between the riser and the foot letting water back in the engine . I have been dealing with them all day to day . my son got a set for OMC 5.7 they told him there was only one kind but they was wrong . The ones he got was to wide , and he started cutting on them so cant take them back Does any know if there is more than one kind.