Clunking starter & water in oil

[Lochlomond]

Hi, looking for some help with engine issue.

Boat maxum 2700scr, inboard mag 350 mpi, bravo leg.

Took the boat out at the weekend, started first time, engine running sweet, oil pressure 40psi, engine temp 170 degrees all normal, ran between 1500 to 3000 rpm for 5 mile journey, beached up for the day/night with no issues or worries, switched of and switched batteries to battery 1. Following morning as usual battery 1 nearly dead so switched to both batteries as usual to fire engine and charge up and it just clicked, did not crank, tried bat 2 on its own and just the same. Some very helpful boaters loaned me fully charged batteries and managed to get it to crank but only for 1-2 seconds finishing with a clunking noise from I think starter motor, played about with different batteries and still the same.

On a comment from someone I decided to check the oil and found it to be milky looking on dipstick. Got towed back to marina and plugged in shore power, tried to start after a few mins, struggled 1st couple of times but then fired up, ran sweetly, switched off and started again first time.

Monday night tried to start and back to a second or two then clunk so went for a set of new batteries. Apologies for the saga but I know the more info usually helps.


Fitted new batteries tonight and no change so def not a battery issue, got talking to a guy at marina who heard me trying to start the engine and he reckons water in cylinders, told me engine struggling to crank as obviously you can't compress water/liquids, I took oil filler cap off and found white sludge and can clearly see water in rocker cover but unsure if head gasket or cracked block as ran sweet for my day out and also when I ran her after being towed back, any ideas guys or checks for me to?

Can't believe it's to be a scorcher all weekend and ill be stuck in marina! Thanks in advance.

 

[tpenfield]

Re: Clunking starter & water in oil

My idea is that you have water in the cylinders and it has mixed with the oil.

The trick is to figure out:

How water is getting in there

What, if any, damage has occurred.


Compression test may tell if you have damage from hydro-locking

Cooling system pressure test may tell if, and where, water is leaking from the cooling system into the engine.

other possibilities of water is back through the exhaust while the boat is anchored, etc. So, maybe check the exhaust shutters.

 

[Lochlomond]

Re: Clunking starter & water in oil

My idea is that you have water in the cylinders and it has mixed with the oil.

The trick is to figure out:

How water is getting in there

What, if any, damage has occurred.


Compression test may tell if you have damage from hydro-locking

Cooling system pressure test may tell if, and where, water is leaking from the cooling system into the engine.

other possibilities of water is back through the exhaust while the boat is anchored, etc. So, maybe check the exhaust shutters.

Hi, thanks for the input, at boat just now removed starter motor and bench tested fine, can see where it has chewed flywheel trying to crank, removed plugs, dry on starboard bank, wet on port side, hand cranked and port side spewed water from cylinders.

So as you said and suspected water in cylinders, not sure if any hydro- locking took place as ran sweetly till I switched of to camp the night, it was the next morning it didn't want to crank suggesting cylinders filled after switching engine off? Maybe shutters?

Taken a cple of photos as some possible tell tale signs on exhaust manifold not sure if that can cause the problems, will do the tests you suggest, if I figure how to upload pics I will.

 

[Bondo]

Re: Clunking starter & water in oil

Hi, thanks for the input, at boat just now removed starter motor and bench tested fine, can see where it has chewed flywheel trying to crank, removed plugs, dry on starboard bank, wet on port side, hand cranked and port side spewed water from cylinders.

So as you said and suspected water in cylinders, not sure if any hydro- locking took place as ran sweetly till I switched of to camp the night, it was the next morning it didn't want to crank suggesting cylinders filled after switching engine off? Maybe shutters?

Taken a cple of photos as some possible tell tale signs on exhaust manifold not sure if that can cause the problems, will do the tests you suggest, if I figure how to upload pics I will.

Ayuh,.... Yer experiencin' Hydro-Lockin', Right Now,.... Water in the cylinders,...

Pull the Riser off the manifold on the side with water in the cylinders,... I'm guessin' it's Junk,...
The other side should atleast be pulled, 'n inspected, if not also Replaced,...

Sounds like the motor's comin' out for a ring gear replacement, Anyways,...
Oughta do a Compression check on the motor too,... Probably bent a rod tryin' to start it,...

 

[whodunnit]

Re: Clunking starter & water in oil

I've got a very similar problem with '87, 260 mercruiser, 5.7 V8. Water in the oil looks like chocolate milk. Oil pan was full when I checked the stick. No starter issues. Engine will run but I don't let it. Due to placement of the engine and construction of the deck, I must remove the exhaust manifolds to access the plugs. I am curious about water possibly entering thru the exhaust manifolds.
What am I looking for in the manifold/ riser on my way to the plugs / cylinders?

 

[Bondo]

Re: Clunking starter & water in oil

I've got a very similar problem with '87, 260 mercruiser, 5.7 V8. Water in the oil looks like chocolate milk. Oil pan was full when I checked the stick. No starter issues. Engine will run but I don't let it. Due to placement of the engine and construction of the deck, I must remove the exhaust manifolds to access the plugs. I am curious about water possibly entering thru the exhaust manifolds.
What am I looking for in the manifold/ riser on my way to the plugs / cylinders?

Ayuh,... Start a thread of yer Own,... No hy-jackin' Lochlomond's,.....

 

[Lochlomond]

Re: Clunking starter & water in oil

Ayuh,.... Yer experiencin' Hydro-Lockin', Right Now,.... Water in the cylinders,...

Pull the Riser off the manifold on the side with water in the cylinders,... I'm guessin' it's Junk,...
The other side should atleast be pulled, 'n inspected, if not also Replaced,...

Sounds like the motor's comin' out for a ring gear replacement, Anyways,...
Oughta do a Compression check on the motor too,... Probably bent a rod tryin' to start it,...

Hi Bondo-o, Sorry I obviously misinterpreted what 'hydro-lockin' actually was doh!

What do you mean by pulling the riser of the manifold? Sorry although mechanically minded not really experienced with engines never mind boat engines, if you could explain a little more ill get right onto it. Thanks

 

[Lochlomond]

Re: Clunking starter & water in oil

Good shout Mr Bond,

 

[aerobat]

Re: Clunking starter & water in oil

Can't believe it's to be a scorcher all weekend and ill be stuck in marina! Thanks in advance.

sorry to say this, but from what you write you have far more problems than be a scorcher for the one weekend .

What do you mean by pulling the riser of the manifold? Sorry although mechanically minded not really experienced with engines never mind boat engines, if you could explain a little more ill get right onto it. Thanks

the riser and manifold have water passages and when cracked they may allow via the valves water into the cylinder which might result in hydrolocking. when you say you are not experienced in boat engines call a good mechanic because pulling the manifold may overload you .

other options would be a blown head gasket / cracked head or a cracked block, but in case of a craked block you should have water in oil only , not the cylinders.

its not the battery and not the starter, you engine is badly hurt.

did you winterized the engine last winter by at least draining it ?

 

[Bondo]

Re: Clunking starter & water in oil

Hi Bondo-o, Sorry I obviously misinterpreted what 'hydro-lockin' actually was doh!

What do you mean by pulling the riser of the manifold? Sorry although mechanically minded not really experienced with engines never mind boat engines, if you could explain a little more ill get right onto it. Thanks

Ayuh,... You've got Alota learnin' to do,...

I suggest several hours up in the Adults Only section, at the top of this forum,...

 

[TilliamWe]

Re: Clunking starter & water in oil

The most common source of water in the cylinders of a marine engine is the exhaust manifolds/risers. That's where you start before you go having the heads removed (headgasket issues are MUCH less common than rusted out/cracked exhaust manifolds). That will also let you see if the exhaust shutters are intact and in place.

 

[Lochlomond]

Re: Clunking starter & water in oil

sorry to say this, but from what you write you have far more problems than be a scorcher for the one weekend .




the riser and manifold have water passages and when cracked they may allow via the valves water into the cylinder which might result in hydrolocking. when you say you are not experienced in boat engines call a good mechanic because pulling the manifold may overload you .

other options would be a blown head gasket / cracked head or a cracked block, but in case of a craked block you should have water in oil only , not the cylinders.

its not the battery and not the starter, you engine is badly hurt.

did you winterized the engine last winter by at least draining it ?

Hi aerobat, I like your humour but its not often the Bonnie banks of Loch Lomond are scorching in the 30 degrees.

I'm going down in the morning to both enjoy the weather and remove the portside riser then exhaust manifold, checking gaskets first to see what I find, if its beyond me then its up to the marine engineer (loosely said) to sort out.

Sadly I've never winterized the engine in the 4 years I've had the boat, just left the tube heater in the engine bay on throughout the winter, maybe a big mistake.

 

[TilliamWe]

Re: Clunking starter & water in oil

Your exhaust manifolds are just as likely rusted out from age as they are cracked from freeze damage.

 

[Lochlomond]

Re: Clunking starter & water in oil

Took the riser and manifold off, not had chance to pressure test but I did fill the cooling pipes on the exhaust manifold and even with no pressure could see water weeping into the manifold so either cracked or rusted out, all the advice has been appreciated guys looks like I have got to the bottom of the problems.