water in oil
- Thread starter gator46
- Start date
kevin27
Well-Known Member
- Aug 8, 2007
- 1,040
- Boat Info
- 2017 Scout 175 sportfish.
2002 Crownline 202 LPX
- Engines
- Yamaha 90hp
Mercruiser 350mag mpi
My guess is rotten/cracked heads. I have seen that happen before. Go to Ebay and find a set of heads. Also check the intake manifold to be sure it's not rotted out and give it a try. I found my head cooling ports were cloged up around the back cylinders causing them to overheat and crack on the 270DA I had. Seems to be common on older RWC engines in saltwater.
Time To Relax
New Member
- Sep 27, 2012
- 222
- Boat Info
- 2008 44 Sundancer
2012 Zodiac 200 Cadet w 2.5 Merc
- Engines
- Twin 8.1L Mercruiser v Drives
Need more details. Are u on lake or saltwater, r single or duel engine, freshwater cooled or raw, r these original engines? Details, how old r engines?
Air O'Nautical
Well-Known Member
- Feb 5, 2008
- 2,316
- Boat Info
- 1995 400EC. Raymarine E80, Tridata, 4kw dome, Garmin 943
- Engines
- 2013 7.4L Mercruiser Blue water.
Hurth straight shaft 630's,
Westerbeke 7.0 BCG
What about the riser gaskets??
Ididntdoit
Well-Known Member
How cold has it gotten there? Could be a cracked block
Air O'Nautical
Well-Known Member
- Feb 5, 2008
- 2,316
- Boat Info
- 1995 400EC. Raymarine E80, Tridata, 4kw dome, Garmin 943
- Engines
- 2013 7.4L Mercruiser Blue water.
Hurth straight shaft 630's,
Westerbeke 7.0 BCG
Oops,
I ment the elbow..not the riser.
The riser is the spacer in between the exhaust manifold and the elbow...if you have one.
The gasket right below the elbow is a possible failure point on marine engines.
Its a three year replacement gasket and every five years you throw out the elbows for new.
If your raw water cooled and in salt water throw away everything raw water cooled every five years on the exhaust system.
It sucks but, engine failure sucks more!
I ment the elbow..not the riser.
The riser is the spacer in between the exhaust manifold and the elbow...if you have one.
The gasket right below the elbow is a possible failure point on marine engines.
Its a three year replacement gasket and every five years you throw out the elbows for new.
If your raw water cooled and in salt water throw away everything raw water cooled every five years on the exhaust system.
It sucks but, engine failure sucks more!
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Does the motor have a heat exchanger for oil cooling?
Sometimes the cooling tubes will leak oil into the coolant that surrounds them.
When was the last time the manifolds / risers were replaced?
When was the last time the manifolds / risers were replaced?
Air O'Nautical
Well-Known Member
- Feb 5, 2008
- 2,316
- Boat Info
- 1995 400EC. Raymarine E80, Tridata, 4kw dome, Garmin 943
- Engines
- 2013 7.4L Mercruiser Blue water.
Hurth straight shaft 630's,
Westerbeke 7.0 BCG
Not really..
Any rust on the outside near the gaskets are a sure sign that its leaking out so, probably in as well. If you pull the elbow and look in the exhaust manifold, there should be no rust at all. It should all be a nice carbon black color. Also, look at the gasket surface for any tracks or rust colored lines that would suggest a gasket leak.
Exhaust components on raw water cooled boats are consumables and need replacing every five years. I've heard of operating in fresh water or a trailer boat that is flushed after every use lasting much, much longer.
If you don't know it's history...you should replace everything to get a start point.
This is where B.O.A.T comes from (break out another thousand).
You might (should i think) have an oil cooler in the raw water inlet hose.
Thats another possible spot to let water in...mentioned already along with other things.
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Air O'Nautical
Well-Known Member
- Feb 5, 2008
- 2,316
- Boat Info
- 1995 400EC. Raymarine E80, Tridata, 4kw dome, Garmin 943
- Engines
- 2013 7.4L Mercruiser Blue water.
Hurth straight shaft 630's,
Westerbeke 7.0 BCG
Pull the plugs and look for a strangely clean plug.
That could indicate water in that cylinder is steam cleaning that plug.
At least you'd know which side is the problem..
That could indicate water in that cylinder is steam cleaning that plug.
At least you'd know which side is the problem..
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Can you contact the P.O and ask when he might or ever had changed the risers and manifolds? It won't fix the problem but it will point you in a correct direction.
johnsross3
Member
If you are unsure of the age of the risers and their gaskets, I'd start there by removing and inspecting them and replacing the gaskets if there are no obstructions (rust blockages) in the risers. They should be put on a three year cycle, so at least start with a date you know you replaced them. I also like Mark's suggestion about inspecting all of your spark plugs for one that is conspicuously clean. Now, if you do find that, hopefully some mechanic will have chimed in about how to test for block versus head and manifold cracks.
Ididntdoit
Well-Known Member
Did you physically remove the drain plugs on each side of the block just above the pan rail and did water flow out of them? Often, these are plugged with casting sand, corrosion, etc an you need to "poke" them out.......If this just started after the cold spell, it is one hell of a coincidence if somthing other than freezing is your problem
