Water in oil. low oil pressure, runs rough...

[Kingsfr]

Hi all.
I have a 2005 270 Sundeck with the 6.2L engine and Bravo3. It was purchased used last year. All last summer it ran fine. We had the marina winterize the engine then recommission it this spring. The engine ran fine for the first couple of outtings, then it started to over heat. I don't believe the temperature ever passed 210 deg as per the SmartCraft readings. The mechanic at the marina found a cracked manifold on the starboard side of the engine. Because this was a 7 year old used boat, I assumed everything was original, so I had him replace both manifolds, both risers, and the 3" extention blocks for the risers. He, also, said that he replaced the Idle Control Valve (?) because he said it was clogged, removed the spark plugs and cranked engine to remove any water in the cylinders, and changed the oil once.
Well, the engine started up and ran fine for the first few times taking it out except that it would not reach full RPMs at WOT. It would only get to about 4200 vs. the normal 4800 before the repairs. Top speed would now be at about 36mph vs. 41-42mph before.
Yesterday, my brother had the boat out. He called me and said there's a big problem. He was cruising at about 3000RPMs when all of a sudden he heard a bang come from the engine and the RPMs suddenly dropped to 2000RPMs, the oil pressure "dropped to nothing" and the alarm beeped. He quickly shut the engine down. He started the engine again after a few minutes, it started right away with no problem. He said there was oil pressure, but it was a lot lower that usual. He wanted to get back to the marina, so he started off slow. When he increased RPMs to about 1200, the engine started to buck and flucuate running rough.
Today, I went down to the boat. I checked the oil and it appears to have water in it. I removed the oil fill cap and found condensation on the inside of the cap. Looking into the fill neck I can see white stuff around the insides. It started fine. Oil pressure was ok, around 44-49psi at idle. It sounded OK. I let the temp rise to its normal 140 deg at idle. I noticed the oil pressure slowly dropping to around 32-35psi. I shut it down. My brother said that the engine never went past 150 deg yesterday, so no overheating problem.
Any opinions? Suggestions? Help?
Thanks,
Tom

 

[JimG]

I would check the sea water impeller to start with. The other problems (cracked manifold, water in the oil) could have been caused by overheating. Fix the water intrusion problem before running again.

There is an outside chance that all of the problems started with improper winterization.

 

[Kingsfr]

I would check the sea water impeller to start with. The other problems (cracked manifold, water in the oil) could have been caused by overheating. Fix the water intrusion problem before running again.

There is an outside chance that all of the problems started with improper winterization.

Thanks for the repy, Jim.
I forgot to mention, the waterpump was replaced when the overheating first started, before the crack in the manifold was discovered.
What are some probable sources for the water intrusion. What would the fix be?
Could you ,also, expand on what could be "improper winterization"?

 

[JimG]

Thanks for the repy, Jim.
I forgot to mention, the waterpump was replaced when the overheating first started, before the crack in the manifold was discovered.
What are some probable sources for the water intrusion. What would the fix be?
Could you ,also, expand on what could be "improper winterization"?

Water intrusion could come from cracked head/block, blown head gasket, or as simple as exhaust flappers.

If winterizing is not properly done, water can freeze in the engine and damage the components mentioned (except the flappers). If the marina that did it is reputable with a good track record, then it's not likely the cause of your problems.

 

[Kingsfr]

I'm going to hope for bad flappers. The other stuff sounds real expensive... the manifolds and risers with extention blocks was a very big (for me) hit at almost $3300. I don't think I could do another big repair.
As far as the marina's mechanics reputation, I don't know. This was our first experience with them.
Thanks again.

 

[Kingsfr]

Where are the exhaust flappers located?

 

[JimG]

Where are the exhaust flappers located?

Normally down in the exhaust tubes... they prevent water from rushing through the exhaust into the manifolds/cylinders when you stop or take on a wave at idle, etc..

 

[Bob & Sue]

First thing I would do is get either SEA TOW or VESSEL ASSIST whichever one is in your area it's around $150.00 a year get towed in next time it will save you 1000's in boat repairs. I would start by doing an oil & filter change first without warming the engine check the oil for water. Then pull all the plugs and crank it over with the kill switch off look for water on the plugs and water coming out of the plug holes. If no water do a compression test. If you have good compression then start the engine for a couple of minutes if there was water in the oil do another oil & filter change or 2 then warm the engine up if it's FWC check the level of antifreeze first. You need to get the water out of the engine asap especially if it's salt water. If it were me I'd find out what is wrong before you start replacing parts if the flappers haven't been changed since new it would be a good idea to change them soon.

 

[Kingsfr]

Bob, thank you. We do have BoatUS towing membership but, my brother didnt think of it at the time. I explained to him that calling to be towed back would have been the better choice.
The engine is not fresh water cooled, and it is kept in a slip so I can't flush with fresh water until I pull it out. As you could probably tell, I am not a very experienced mechanic...I know some of the basics, but I'm not very comfortable doing major work on my own. Today, I asked the marina mechanic to diagnose the problem and let me know what it is. I don't know if I could pay for another big repair bill right after the last bill.
Thanks for the info and suggestions.
Tom

 

[wakeup 19]

Sorry to say but I think your engine maybe cooked. sounds like a similar problem I had. will run but oil pressure/compression is gone. Good Luck

 

[northern]

The engine oil cooler could have a small keak in it. That happened to me once. I got water in the oil when the engine cooled. The oil pressure dropped as it was leaking oil out of the system when the motor was running. INexpensive to have checked at a rad shop.

 

[Bob & Sue]

Bob, thank you. We do have BoatUS towing membership but, my brother didn't think of it at the time. I explained to him that calling to be towed back would have been the better choice.
The engine is not fresh water cooled, and it is kept in a slip so I can't flush with fresh water until I pull it out. As you could probably tell, I am not a very experienced mechanic...I know some of the basics, but I'm not very comfortable doing major work on my own. Today, I asked the marina mechanic to diagnose the problem and let me know what it is. I don't know if I could pay for another big repair bill right after the last bill.
Thanks for the info and suggestions.
Tom

You may want to look into a system like Salt Away after your boat is repaired it can be used while your in the slip without hauling it out this stuff works and will protect your new manifolds and risers you know the cost of replacement. I have dry rack storage they run it through before storing the boat. Just started using their spray on it seems to make salt crystals disappear even after the salt has dried on the boat without much effort.

http://www.saltawayproducts.com/MarineApp.htm

 

[Kingsfr]

Thank you all for the info and suggestions. The latest is...the mechanic checked out the engine briefly on Sat. He said the outdrive checked out ok. Then came the bad news...he said there are metal filings in the oil. A pic of the oil were the oil filter was removed was sent to me showing little bits of stuff in the oil. He can not get back to checking the engine until Tues.
I'm going to take a wild guess and say that metal filings in the oil is a very bad thing...

 

[troc]

Thank you all for the info and suggestions. The latest is...the mechanic checked out the engine briefly on Sat. He said the outdrive checked out ok. Then came the bad news...he said there are metal filings in the oil. A pic of the oil were the oil filter was removed was sent to me showing little bits of stuff in the oil. He can not get back to checking the engine until Tues.
I'm going to take a wild guess and say that metal filings in the oil is a very bad thing...

Take the oil filter off and CAREFULLY cut it open without making any metal chips pull out the filter media and inspect what type of metal if any is in there.. ie babbit,chrome . It will give you a good idea where to start looking. good luck

 

[Kingsfr]

Well, I went to see the mechanic and the engine the other day. The engine was out of the boat hanging from a chain...not a good sight. He, first, showed me the oil pan that he removed. It had a lot of metal bits on the bottom. Then he lifted the engine high enough to look under and see the insides. He pointed out a burn mark on what I think he said was the main bearing. He said that the engine must have run for awhile with water in the oil, reducing the lubricating ability of the oil, thus, causing the damage... I need a new longblock.
I've been doing some research and considering my options. I can either replace only the longblock on the existing engine using all the other parts from the old engine, or I could buy a "new" drop-in engine that comes with a 3 year warranty with all new parts.
I'm thinking about repowering with a Mercury Factory Remanufactured Plus Series 383 MAG Stroker Bravo MPI drop-in. The warranty is a big plus for peace of mind and I believe all the other parts from the old engine can be used as spare replacement parts on the new engine, including the water pump, starter, manifolds and risers that were just installed on the old engine a few weeks ago.
My thinking is that I dont want to put more money into the existing 6.2L then have something else go wrong with it. Ill be kicking myself saying I should've spent a "little" more money and got a brand new engine with 0 hrs and a 3 year warranty.
I'm assuming the 383Stroker will have very similar performance as the original 377 6.2L MPI.
Any thoughts?

 

[wakeup 19]

That stinks! Did you/mech ever find the source of the problem?

 

[Kingsfr]

That stinks! Did you/mech ever find the source of the problem?

Not yet. Ill ask him to, or allow me to, dismantle the old engine after the work is done. He said he will check the exhaust flappers before the new install. I suspect a blown head gasket that went undetected when the other work was done...but that is just a guess.

 

[Kingsfr]

Well... we had a new Mercruiser 383 MAG Stroker installed. Took it out for a short test run this morning. All seems good. The 20 hour break in period begins. I had the mechanic install a Perko flush kit to the new engine so we can flush out all the salt at the end of the day. I don't know why every marine engine doesn't come with one...actually, I do know why. So that the engines don't last too long and you have to buy a new one...
Does anyone know of an engine machine shop or anyplace else on Long Island that would be interested in a 2005 6.2L engine that has a longblock that needs work? The engine has about 360 hours on it, but the starter, waterpump, manifolds, risers and 3" extention blocks have less that 1 hour.